diff options
| author |  letouzey <letouzey@85f007b7-540e-0410-9357-904b9bb8a0f7> | 2009-11-10 11:19:25 +0000 |
|---|---|---|
| committer | letouzey <letouzey@85f007b7-540e-0410-9357-904b9bb8a0f7> | 2009-11-10 11:19:25 +0000 |
| commit | e8b2255678a7fa1c140c4a50dca26cc94ac1a6e0 (patch) | |
| tree | e1dcc1538e1ce09783a7d4fccc94c6aeb75b29e0 /theories/Numbers | |
| parent | 424b20ed34966506cef31abf85e3e3911138f0fc (diff) | |
Simplification of Numbers, mainly thanks to Include
- No more nesting of Module and Module Type, we rather use Include.
- Instead of in-name-qualification like NZeq, we use uniform
short names + modular qualification like N.eq when necessary.
- Many simplification of proofs, by some autorewrite for instance
- In NZOrder, we instantiate an "order" tactic.
- Some requirements in NZAxioms were superfluous: compatibility
of le, min and max could be derived from the rest.
- NMul removed, since it was containing only an ad-hoc result for
ZNatPairs, that we've inlined in the proof of mul_wd there.
- Zdomain removed (was already not compiled), idea of a module
with eq and eqb reused in DecidableType.BooleanEqualityType.
- ZBinDefs don't contain any definition now, migrate it to ZBinary.
git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@12489 85f007b7-540e-0410-9357-904b9bb8a0f7
Diffstat (limited to 'theories/Numbers')
55 files changed, 2290 insertions, 3849 deletions
diff --git a/theories/Numbers/BigNumPrelude.v b/theories/Numbers/BigNumPrelude.v index 3a64a8dc1..08da68444 100644 --- a/theories/Numbers/BigNumPrelude.v +++ b/theories/Numbers/BigNumPrelude.v @@ -30,7 +30,7 @@ Declare ML Module "numbers_syntax_plugin". *) -Open Local Scope Z_scope. +Local Open Scope Z_scope. (* For compatibility of scripts, weaker version of some lemmas of Zdiv *) diff --git a/theories/Numbers/Cyclic/Abstract/CyclicAxioms.v b/theories/Numbers/Cyclic/Abstract/CyclicAxioms.v index 32d150331..9ad1d019e 100644 --- a/theories/Numbers/Cyclic/Abstract/CyclicAxioms.v +++ b/theories/Numbers/Cyclic/Abstract/CyclicAxioms.v @@ -22,7 +22,7 @@ Require Import Znumtheory. Require Import BigNumPrelude. Require Import DoubleType. -Open Local Scope Z_scope. +Local Open Scope Z_scope. (** First, a description via an operator record and a spec record. *) diff --git a/theories/Numbers/Cyclic/Abstract/NZCyclic.v b/theories/Numbers/Cyclic/Abstract/NZCyclic.v index 2076a9ab2..b99df747a 100644 --- a/theories/Numbers/Cyclic/Abstract/NZCyclic.v +++ b/theories/Numbers/Cyclic/Abstract/NZCyclic.v @@ -25,71 +25,72 @@ Require Import CyclicAxioms. Module NZCyclicAxiomsMod (Import Cyclic : CyclicType) <: NZAxiomsSig. -Open Local Scope Z_scope. +Local Open Scope Z_scope. -Definition NZ := w. +Definition t := w. -Definition NZ_to_Z : NZ -> Z := znz_to_Z w_op. -Definition Z_to_NZ : Z -> NZ := znz_of_Z w_op. -Notation Local wB := (base w_op.(znz_digits)). +Definition NZ_to_Z : t -> Z := znz_to_Z w_op. +Definition Z_to_NZ : Z -> t := znz_of_Z w_op. +Local Notation wB := (base w_op.(znz_digits)). -Notation Local "[| x |]" := (w_op.(znz_to_Z) x) (at level 0, x at level 99). +Local Notation "[| x |]" := (w_op.(znz_to_Z) x) (at level 0, x at level 99). -Definition NZeq (n m : NZ) := [| n |] = [| m |]. -Definition NZ0 := w_op.(znz_0). -Definition NZsucc := w_op.(znz_succ). -Definition NZpred := w_op.(znz_pred). -Definition NZadd := w_op.(znz_add). -Definition NZsub := w_op.(znz_sub). -Definition NZmul := w_op.(znz_mul). +Definition eq (n m : t) := [| n |] = [| m |]. +Definition zero := w_op.(znz_0). +Definition succ := w_op.(znz_succ). +Definition pred := w_op.(znz_pred). +Definition add := w_op.(znz_add). +Definition sub := w_op.(znz_sub). +Definition mul := w_op.(znz_mul). -Instance NZeq_equiv : Equivalence NZeq. +Delimit Scope NumScope with Num. +Bind Scope NumScope with t. +Local Open Scope NumScope. +Notation "x == y" := (eq x y) (at level 70) : NumScope. +Notation "0" := zero : NumScope. +Notation S := succ. +Notation P := pred. +Notation "x + y" := (add x y) : NumScope. +Notation "x - y" := (sub x y) : NumScope. +Notation "x * y" := (mul x y) : NumScope. -Instance NZsucc_wd : Proper (NZeq ==> NZeq) NZsucc. + +Hint Rewrite w_spec.(spec_0) w_spec.(spec_succ) w_spec.(spec_pred) + w_spec.(spec_add) w_spec.(spec_mul) w_spec.(spec_sub) : w. +Ltac wsimpl := + unfold eq, zero, succ, pred, add, sub, mul; autorewrite with w. +Ltac wcongruence := repeat red; intros; wsimpl; congruence. + +Instance eq_equiv : Equivalence eq. + +Instance succ_wd : Proper (eq ==> eq) succ. Proof. -unfold NZeq; intros n m H. do 2 rewrite w_spec.(spec_succ). now rewrite H. +wcongruence. Qed. -Instance NZpred_wd : Proper (NZeq ==> NZeq) NZpred. +Instance pred_wd : Proper (eq ==> eq) pred. Proof. -unfold NZeq; intros n m H. do 2 rewrite w_spec.(spec_pred). now rewrite H. +wcongruence. Qed. -Instance NZadd_wd : Proper (NZeq ==> NZeq ==> NZeq) NZadd. +Instance add_wd : Proper (eq ==> eq ==> eq) add. Proof. -unfold NZeq; intros n1 n2 H1 m1 m2 H2. do 2 rewrite w_spec.(spec_add). -now rewrite H1, H2. +wcongruence. Qed. -Instance NZsub_wd : Proper (NZeq ==> NZeq ==> NZeq) NZsub. +Instance sub_wd : Proper (eq ==> eq ==> eq) sub. Proof. -unfold NZeq; intros n1 n2 H1 m1 m2 H2. do 2 rewrite w_spec.(spec_sub). -now rewrite H1, H2. +wcongruence. Qed. -Instance NZmul_wd : Proper (NZeq ==> NZeq ==> NZeq) NZmul. +Instance mul_wd : Proper (eq ==> eq ==> eq) mul. Proof. -unfold NZeq; intros n1 n2 H1 m1 m2 H2. do 2 rewrite w_spec.(spec_mul). -now rewrite H1, H2. +wcongruence. Qed. -Delimit Scope IntScope with Int. -Bind Scope IntScope with NZ. -Open Local Scope IntScope. -Notation "x == y" := (NZeq x y) (at level 70) : IntScope. -Notation "x ~= y" := (~ NZeq x y) (at level 70) : IntScope. -Notation "0" := NZ0 : IntScope. -Notation S x := (NZsucc x). -Notation P x := (NZpred x). -(*Notation "1" := (S 0) : IntScope.*) -Notation "x + y" := (NZadd x y) : IntScope. -Notation "x - y" := (NZsub x y) : IntScope. -Notation "x * y" := (NZmul x y) : IntScope. - Theorem gt_wB_1 : 1 < wB. Proof. -unfold base. -apply Zpower_gt_1; unfold Zlt; auto with zarith. +unfold base. apply Zpower_gt_1; unfold Zlt; auto with zarith. Qed. Theorem gt_wB_0 : 0 < wB. @@ -97,7 +98,7 @@ Proof. pose proof gt_wB_1; auto with zarith. Qed. -Lemma NZsucc_mod_wB : forall n : Z, (n + 1) mod wB = ((n mod wB) + 1) mod wB. +Lemma succ_mod_wB : forall n : Z, (n + 1) mod wB = ((n mod wB) + 1) mod wB. Proof. intro n. pattern 1 at 2. replace 1 with (1 mod wB). rewrite <- Zplus_mod. @@ -105,7 +106,7 @@ reflexivity. now rewrite Zmod_small; [ | split; [auto with zarith | apply gt_wB_1]]. Qed. -Lemma NZpred_mod_wB : forall n : Z, (n - 1) mod wB = ((n mod wB) - 1) mod wB. +Lemma pred_mod_wB : forall n : Z, (n - 1) mod wB = ((n mod wB) - 1) mod wB. Proof. intro n. pattern 1 at 2. replace 1 with (1 mod wB). rewrite <- Zminus_mod. @@ -113,31 +114,32 @@ reflexivity. now rewrite Zmod_small; [ | split; [auto with zarith | apply gt_wB_1]]. Qed. -Lemma NZ_to_Z_mod : forall n : NZ, [| n |] mod wB = [| n |]. +Lemma NZ_to_Z_mod : forall n, [| n |] mod wB = [| n |]. Proof. intro n; rewrite Zmod_small. reflexivity. apply w_spec.(spec_to_Z). Qed. -Theorem NZpred_succ : forall n : NZ, P (S n) == n. +Theorem pred_succ : forall n, P (S n) == n. Proof. -intro n; unfold NZsucc, NZpred, NZeq. rewrite w_spec.(spec_pred), w_spec.(spec_succ). -rewrite <- NZpred_mod_wB. +intro n. wsimpl. +rewrite <- pred_mod_wB. replace ([| n |] + 1 - 1)%Z with [| n |] by auto with zarith. apply NZ_to_Z_mod. Qed. -Lemma Z_to_NZ_0 : Z_to_NZ 0%Z == 0%Int. +Lemma Z_to_NZ_0 : Z_to_NZ 0%Z == 0%Num. Proof. -unfold NZeq, NZ_to_Z, Z_to_NZ. rewrite znz_of_Z_correct. -symmetry; apply w_spec.(spec_0). +unfold NZ_to_Z, Z_to_NZ. wsimpl. +rewrite znz_of_Z_correct; auto. exact w_spec. split; [auto with zarith |apply gt_wB_0]. Qed. Section Induction. -Variable A : NZ -> Prop. -Hypothesis A_wd : Proper (NZeq ==> iff) A. +Variable A : t -> Prop. +Hypothesis A_wd : Proper (eq ==> iff) A. Hypothesis A0 : A 0. -Hypothesis AS : forall n : NZ, A n <-> A (S n). (* Below, we use only -> direction *) +Hypothesis AS : forall n, A n <-> A (S n). + (* Below, we use only -> direction *) Let B (n : Z) := A (Z_to_NZ n). @@ -150,8 +152,8 @@ Lemma BS : forall n : Z, 0 <= n -> n < wB - 1 -> B n -> B (n + 1). Proof. intros n H1 H2 H3. unfold B in *. apply -> AS in H3. -setoid_replace (Z_to_NZ (n + 1)) with (S (Z_to_NZ n)) using relation NZeq. assumption. -unfold NZeq. rewrite w_spec.(spec_succ). +setoid_replace (Z_to_NZ (n + 1)) with (S (Z_to_NZ n)). assumption. +wsimpl. unfold NZ_to_Z, Z_to_NZ. do 2 (rewrite znz_of_Z_correct; [ | exact w_spec | auto with zarith]). symmetry; apply Zmod_small; auto with zarith. @@ -164,11 +166,11 @@ apply Zbounded_induction with wB. apply B0. apply BS. assumption. assumption. Qed. -Theorem NZinduction : forall n : NZ, A n. +Theorem bi_induction : forall n, A n. Proof. -intro n. setoid_replace n with (Z_to_NZ (NZ_to_Z n)) using relation NZeq. +intro n. setoid_replace n with (Z_to_NZ (NZ_to_Z n)). apply B_holds. apply w_spec.(spec_to_Z). -unfold NZeq, NZ_to_Z, Z_to_NZ; rewrite znz_of_Z_correct. +unfold eq, NZ_to_Z, Z_to_NZ; rewrite znz_of_Z_correct. reflexivity. exact w_spec. apply w_spec.(spec_to_Z). @@ -176,47 +178,40 @@ Qed. End Induction. -Theorem NZadd_0_l : forall n : NZ, 0 + n == n. +Theorem add_0_l : forall n, 0 + n == n. Proof. -intro n; unfold NZadd, NZ0, NZeq. rewrite w_spec.(spec_add). rewrite w_spec.(spec_0). +intro n. wsimpl. rewrite Zplus_0_l. rewrite Zmod_small; [reflexivity | apply w_spec.(spec_to_Z)]. Qed. -Theorem NZadd_succ_l : forall n m : NZ, (S n) + m == S (n + m). +Theorem add_succ_l : forall n m, (S n) + m == S (n + m). Proof. -intros n m; unfold NZadd, NZsucc, NZeq. rewrite w_spec.(spec_add). -do 2 rewrite w_spec.(spec_succ). rewrite w_spec.(spec_add). -rewrite NZsucc_mod_wB. repeat rewrite Zplus_mod_idemp_l; try apply gt_wB_0. +intros n m. wsimpl. +rewrite succ_mod_wB. repeat rewrite Zplus_mod_idemp_l; try apply gt_wB_0. rewrite <- (Zplus_assoc ([| n |] mod wB) 1 [| m |]). rewrite Zplus_mod_idemp_l. rewrite (Zplus_comm 1 [| m |]); now rewrite Zplus_assoc. Qed. -Theorem NZsub_0_r : forall n : NZ, n - 0 == n. +Theorem sub_0_r : forall n, n - 0 == n. Proof. -intro n; unfold NZsub, NZ0, NZeq. rewrite w_spec.(spec_sub). -rewrite w_spec.(spec_0). rewrite Zminus_0_r. apply NZ_to_Z_mod. +intro n. wsimpl. rewrite Zminus_0_r. apply NZ_to_Z_mod. Qed. -Theorem NZsub_succ_r : forall n m : NZ, n - (S m) == P (n - m). +Theorem sub_succ_r : forall n m, n - (S m) == P (n - m). Proof. -intros n m; unfold NZsub, NZsucc, NZpred, NZeq. -rewrite w_spec.(spec_pred). do 2 rewrite w_spec.(spec_sub). -rewrite w_spec.(spec_succ). rewrite Zminus_mod_idemp_r. -rewrite Zminus_mod_idemp_l. -now replace ([|n|] - ([|m|] + 1))%Z with ([|n|] - [|m|] - 1)%Z by auto with zarith. +intros n m. wsimpl. rewrite Zminus_mod_idemp_r, Zminus_mod_idemp_l. +now replace ([|n|] - ([|m|] + 1))%Z with ([|n|] - [|m|] - 1)%Z + by auto with zarith. Qed. -Theorem NZmul_0_l : forall n : NZ, 0 * n == 0. +Theorem mul_0_l : forall n, 0 * n == 0. Proof. -intro n; unfold NZmul, NZ0, NZ, NZeq. rewrite w_spec.(spec_mul). -rewrite w_spec.(spec_0). now rewrite Zmult_0_l. +intro n. wsimpl. now rewrite Zmult_0_l. Qed. -Theorem NZmul_succ_l : forall n m : NZ, (S n) * m == n * m + m. +Theorem mul_succ_l : forall n m, (S n) * m == n * m + m. Proof. -intros n m; unfold NZmul, NZsucc, NZadd, NZeq. rewrite w_spec.(spec_mul). -rewrite w_spec.(spec_add), w_spec.(spec_mul), w_spec.(spec_succ). -rewrite Zplus_mod_idemp_l, Zmult_mod_idemp_l. +intros n m. wsimpl. rewrite Zplus_mod_idemp_l, Zmult_mod_idemp_l. now rewrite Zmult_plus_distr_l, Zmult_1_l. Qed. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleAdd.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleAdd.v index b4f6a8160..aa798e1c7 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleAdd.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleAdd.v @@ -17,7 +17,7 @@ Require Import BigNumPrelude. Require Import DoubleType. Require Import DoubleBase. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section DoubleAdd. Variable w : Type. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleBase.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleBase.v index 82480fa2e..88c34915d 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleBase.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleBase.v @@ -16,7 +16,7 @@ Require Import ZArith. Require Import BigNumPrelude. Require Import DoubleType. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section DoubleBase. Variable w : Type. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleCyclic.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleCyclic.v index db3b622b0..eea29e7ca 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleCyclic.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleCyclic.v @@ -25,7 +25,7 @@ Require Import DoubleDivn1. Require Import DoubleDiv. Require Import CyclicAxioms. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section Z_2nZ. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v index 89c37c0f9..9204b4e05 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v @@ -20,7 +20,7 @@ Require Import DoubleDivn1. Require Import DoubleAdd. Require Import DoubleSub. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Ltac zarith := auto with zarith. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleDivn1.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleDivn1.v index fd6718e4e..386bbb9e5 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleDivn1.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleDivn1.v @@ -17,7 +17,7 @@ Require Import BigNumPrelude. Require Import DoubleType. Require Import DoubleBase. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section GENDIVN1. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleLift.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleLift.v index 28dff1a29..21e694e57 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleLift.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleLift.v @@ -17,7 +17,7 @@ Require Import BigNumPrelude. Require Import DoubleType. Require Import DoubleBase. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section DoubleLift. Variable w : Type. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleMul.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleMul.v index b215f6a86..7090c76a8 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleMul.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleMul.v @@ -17,7 +17,7 @@ Require Import BigNumPrelude. Require Import DoubleType. Require Import DoubleBase. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section DoubleMul. Variable w : Type. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v index ac2232cc0..83a2e7177 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleSqrt.v @@ -17,7 +17,7 @@ Require Import BigNumPrelude. Require Import DoubleType. Require Import DoubleBase. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section DoubleSqrt. Variable w : Type. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleSub.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleSub.v index d3a08c6e0..a7e556713 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleSub.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleSub.v @@ -17,7 +17,7 @@ Require Import BigNumPrelude. Require Import DoubleType. Require Import DoubleBase. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section DoubleSub. Variable w : Type. diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleType.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleType.v index 3bd4b8127..88cbb484f 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleType.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleType.v @@ -13,7 +13,7 @@ Set Implicit Arguments. Require Import ZArith. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Definition base digits := Zpower 2 (Zpos digits). diff --git a/theories/Numbers/Cyclic/Int31/Cyclic31.v b/theories/Numbers/Cyclic/Int31/Cyclic31.v index 6e71bad82..67d15b499 100644 --- a/theories/Numbers/Cyclic/Int31/Cyclic31.v +++ b/theories/Numbers/Cyclic/Int31/Cyclic31.v @@ -1182,11 +1182,11 @@ End Int31_Op. Section Int31_Spec. - Open Local Scope Z_scope. + Local Open Scope Z_scope. Notation "[| x |]" := (phi x) (at level 0, x at level 99). - Notation Local wB := (2 ^ (Z_of_nat size)). + Local Notation wB := (2 ^ (Z_of_nat size)). Lemma wB_pos : wB > 0. Proof. diff --git a/theories/Numbers/Cyclic/ZModulo/ZModulo.v b/theories/Numbers/Cyclic/ZModulo/ZModulo.v index 1b1283400..4f0f6c7c4 100644 --- a/theories/Numbers/Cyclic/ZModulo/ZModulo.v +++ b/theories/Numbers/Cyclic/ZModulo/ZModulo.v @@ -24,7 +24,7 @@ Require Import BigNumPrelude. Require Import DoubleType. Require Import CyclicAxioms. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Section ZModulo. diff --git a/theories/Numbers/Integer/Abstract/ZAdd.v b/theories/Numbers/Integer/Abstract/ZAdd.v index daa7c530b..26ba0a8d4 100644 --- a/theories/Numbers/Integer/Abstract/ZAdd.v +++ b/theories/Numbers/Integer/Abstract/ZAdd.v @@ -12,334 +12,283 @@ Require Export ZBase. -Module ZAddPropFunct (Import ZAxiomsMod : ZAxiomsSig). -Module Export ZBasePropMod := ZBasePropFunct ZAxiomsMod. -Open Local Scope IntScope. +Module ZAddPropFunct (Import Z : ZAxiomsSig). +Include ZBasePropFunct Z. +Local Open Scope NumScope. -Theorem Zadd_wd : - forall n1 n2 : Z, n1 == n2 -> forall m1 m2 : Z, m1 == m2 -> n1 + m1 == n2 + m2. -Proof NZadd_wd. +(** Theorems that are either not valid on N or have different proofs + on N and Z *) -Theorem Zadd_0_l : forall n : Z, 0 + n == n. -Proof NZadd_0_l. - -Theorem Zadd_succ_l : forall n m : Z, (S n) + m == S (n + m). -Proof NZadd_succ_l. - -Theorem Zsub_0_r : forall n : Z, n - 0 == n. -Proof NZsub_0_r. - -Theorem Zsub_succ_r : forall n m : Z, n - (S m) == P (n - m). -Proof NZsub_succ_r. - -Theorem Zopp_0 : - 0 == 0. -Proof Zopp_0. - -Theorem Zopp_succ : forall n : Z, - (S n) == P (- n). -Proof Zopp_succ. - -(* Theorems that are valid for both natural numbers and integers *) - -Theorem Zadd_0_r : forall n : Z, n + 0 == n. -Proof NZadd_0_r. - -Theorem Zadd_succ_r : forall n m : Z, n + S m == S (n + m). -Proof NZadd_succ_r. - -Theorem Zadd_comm : forall n m : Z, n + m == m + n. -Proof NZadd_comm. - -Theorem Zadd_assoc : forall n m p : Z, n + (m + p) == (n + m) + p. -Proof NZadd_assoc. - -Theorem Zadd_shuffle1 : forall n m p q : Z, (n + m) + (p + q) == (n + p) + (m + q). -Proof NZadd_shuffle1. - -Theorem Zadd_shuffle2 : forall n m p q : Z, (n + m) + (p + q) == (n + q) + (m + p). -Proof NZadd_shuffle2. - -Theorem Zadd_1_l : forall n : Z, 1 + n == S n. -Proof NZadd_1_l. - -Theorem Zadd_1_r : forall n : Z, n + 1 == S n. -Proof NZadd_1_r. - -Theorem Zadd_cancel_l : forall n m p : Z, p + n == p + m <-> n == m. -Proof NZadd_cancel_l. - -Theorem Zadd_cancel_r : forall n m p : Z, n + p == m + p <-> n == m. -Proof NZadd_cancel_r. - -(* Theorems that are either not valid on N or have different proofs on N and Z *) - -Theorem Zadd_pred_l : forall n m : Z, P n + m == P (n + m). +Theorem add_pred_l : forall n m, P n + m == P (n + m). Proof. intros n m. -rewrite <- (Zsucc_pred n) at 2. -rewrite Zadd_succ_l. now rewrite Zpred_succ. +rewrite <- (succ_pred n) at 2. +rewrite add_succ_l. now rewrite pred_succ. Qed. -Theorem Zadd_pred_r : forall n m : Z, n + P m == P (n + m). +Theorem add_pred_r : forall n m, n + P m == P (n + m). Proof. -intros n m; rewrite (Zadd_comm n (P m)), (Zadd_comm n m); -apply Zadd_pred_l. +intros n m; rewrite (add_comm n (P m)), (add_comm n m); +apply add_pred_l. Qed. -Theorem Zadd_opp_r : forall n m : Z, n + (- m) == n - m. +Theorem add_opp_r : forall n m, n + (- m) == n - m. Proof. -NZinduct m. -rewrite Zopp_0; rewrite Zsub_0_r; now rewrite Zadd_0_r. -intro m. rewrite Zopp_succ, Zsub_succ_r, Zadd_pred_r; now rewrite Zpred_inj_wd. +nzinduct m. +rewrite opp_0; rewrite sub_0_r; now rewrite add_0_r. +intro m. rewrite opp_succ, sub_succ_r, add_pred_r; now rewrite pred_inj_wd. Qed. -Theorem Zsub_0_l : forall n : Z, 0 - n == - n. +Theorem sub_0_l : forall n, 0 - n == - n. Proof. -intro n; rewrite <- Zadd_opp_r; now rewrite Zadd_0_l. +intro n; rewrite <- add_opp_r; now rewrite add_0_l. Qed. -Theorem Zsub_succ_l : forall n m : Z, S n - m == S (n - m). +Theorem sub_succ_l : forall n m, S n - m == S (n - m). Proof. -intros n m; do 2 rewrite <- Zadd_opp_r; now rewrite Zadd_succ_l. +intros n m; do 2 rewrite <- add_opp_r; now rewrite add_succ_l. Qed. -Theorem Zsub_pred_l : forall n m : Z, P n - m == P (n - m). +Theorem sub_pred_l : forall n m, P n - m == P (n - m). Proof. -intros n m. rewrite <- (Zsucc_pred n) at 2. -rewrite Zsub_succ_l; now rewrite Zpred_succ. +intros n m. rewrite <- (succ_pred n) at 2. +rewrite sub_succ_l; now rewrite pred_succ. Qed. -Theorem Zsub_pred_r : forall n m : Z, n - (P m) == S (n - m). +Theorem sub_pred_r : forall n m, n - (P m) == S (n - m). Proof. -intros n m. rewrite <- (Zsucc_pred m) at 2. -rewrite Zsub_succ_r; now rewrite Zsucc_pred. +intros n m. rewrite <- (succ_pred m) at 2. +rewrite sub_succ_r; now rewrite succ_pred. Qed. -Theorem Zopp_pred : forall n : Z, - (P n) == S (- n). +Theorem opp_pred : forall n, - (P n) == S (- n). Proof. -intro n. rewrite <- (Zsucc_pred n) at 2. -rewrite Zopp_succ. now rewrite Zsucc_pred. +intro n. rewrite <- (succ_pred n) at 2. +rewrite opp_succ. now rewrite succ_pred. Qed. -Theorem Zsub_diag : forall n : Z, n - n == 0. +Theorem sub_diag : forall n, n - n == 0. Proof. -NZinduct n. -now rewrite Zsub_0_r. -intro n. rewrite Zsub_succ_r, Zsub_succ_l; now rewrite Zpred_succ. +nzinduct n. +now rewrite sub_0_r. +intro n. rewrite sub_succ_r, sub_succ_l; now rewrite pred_succ. Qed. -Theorem Zadd_opp_diag_l : forall n : Z, - n + n == 0. +Theorem add_opp_diag_l : forall n, - n + n == 0. Proof. -intro n; now rewrite Zadd_comm, Zadd_opp_r, Zsub_diag. +intro n; now rewrite add_comm, add_opp_r, sub_diag. Qed. -Theorem Zadd_opp_diag_r : forall n : Z, n + (- n) == 0. +Theorem add_opp_diag_r : forall n, n + (- n) == 0. Proof. -intro n; rewrite Zadd_comm; apply Zadd_opp_diag_l. +intro n; rewrite add_comm; apply add_opp_diag_l. Qed. -Theorem Zadd_opp_l : forall n m : Z, - m + n == n - m. +Theorem add_opp_l : forall n m, - m + n == n - m. Proof. -intros n m; rewrite <- Zadd_opp_r; now rewrite Zadd_comm. +intros n m; rewrite <- add_opp_r; now rewrite add_comm. Qed. -Theorem Zadd_sub_assoc : forall n m p : Z, n + (m - p) == (n + m) - p. +Theorem add_sub_assoc : forall n m p, n + (m - p) == (n + m) - p. Proof. -intros n m p; do 2 rewrite <- Zadd_opp_r; now rewrite Zadd_assoc. +intros n m p; do 2 rewrite <- add_opp_r; now rewrite add_assoc. Qed. -Theorem Zopp_involutive : forall n : Z, - (- n) == n. +Theorem opp_involutive : forall n, - (- n) == n. Proof. -NZinduct n. -now do 2 rewrite Zopp_0. -intro n. rewrite Zopp_succ, Zopp_pred; now rewrite Zsucc_inj_wd. +nzinduct n. +now do 2 rewrite opp_0. +intro n. rewrite opp_succ, opp_pred; now rewrite succ_inj_wd. Qed. -Theorem Zopp_add_distr : forall n m : Z, - (n + m) == - n + (- m). +Theorem opp_add_distr : forall n m, - (n + m) == - n + (- m). Proof. -intros n m; NZinduct n. -rewrite Zopp_0; now do 2 rewrite Zadd_0_l. -intro n. rewrite Zadd_succ_l; do 2 rewrite Zopp_succ; rewrite Zadd_pred_l. -now rewrite Zpred_inj_wd. +intros n m; nzinduct n. +rewrite opp_0; now do 2 rewrite add_0_l. +intro n. rewrite add_succ_l; do 2 rewrite opp_succ; rewrite add_pred_l. +now rewrite pred_inj_wd. Qed. -Theorem Zopp_sub_distr : forall n m : Z, - (n - m) == - n + m. +Theorem opp_sub_distr : forall n m, - (n - m) == - n + m. Proof. -intros n m; rewrite <- Zadd_opp_r, Zopp_add_distr. -now rewrite Zopp_involutive. +intros n m; rewrite <- add_opp_r, opp_add_distr. +now rewrite opp_involutive. Qed. -Theorem Zopp_inj : forall n m : Z, - n == - m -> n == m. +Theorem opp_inj : forall n m, - n == - m -> n == m. Proof. -intros n m H. apply Zopp_wd in H. now do 2 rewrite Zopp_involutive in H. +intros n m H. apply opp_wd in H. now do 2 rewrite opp_involutive in H. Qed. -Theorem Zopp_inj_wd : forall n m : Z, - n == - m <-> n == m. +Theorem opp_inj_wd : forall n m, - n == - m <-> n == m. Proof. -intros n m; split; [apply Zopp_inj | apply Zopp_wd]. +intros n m; split; [apply opp_inj | apply opp_wd]. Qed. -Theorem Zeq_opp_l : forall n m : Z, - n == m <-> n == - m. +Theorem eq_opp_l : forall n m, - n == m <-> n == - m. Proof. -intros n m. now rewrite <- (Zopp_inj_wd (- n) m), Zopp_involutive. +intros n m. now rewrite <- (opp_inj_wd (- n) m), opp_involutive. Qed. -Theorem Zeq_opp_r : forall n m : Z, n == - m <-> - n == m. +Theorem eq_opp_r : forall n m, n == - m <-> - n == m. Proof. -symmetry; apply Zeq_opp_l. +symmetry; apply eq_opp_l. Qed. -Theorem Zsub_add_distr : forall n m p : Z, n - (m + p) == (n - m) - p. +Theorem sub_add_distr : forall n m p, n - (m + p) == (n - m) - p. Proof. -intros n m p; rewrite <- Zadd_opp_r, Zopp_add_distr, Zadd_assoc. -now do 2 rewrite Zadd_opp_r. +intros n m p; rewrite <- add_opp_r, opp_add_distr, add_assoc. +now do 2 rewrite add_opp_r. Qed. -Theorem Zsub_sub_distr : forall n m p : Z, n - (m - p) == (n - m) + p. +Theorem sub_sub_distr : forall n m p, n - (m - p) == (n - m) + p. Proof. -intros n m p; rewrite <- Zadd_opp_r, Zopp_sub_distr, Zadd_assoc. -now rewrite Zadd_opp_r. +intros n m p; rewrite <- add_opp_r, opp_sub_distr, add_assoc. +now rewrite add_opp_r. Qed. -Theorem sub_opp_l : forall n m : Z, - n - m == - m - n. +Theorem sub_opp_l : forall n m, - n - m == - m - n. Proof. -intros n m. do 2 rewrite <- Zadd_opp_r. now rewrite Zadd_comm. +intros n m. do 2 rewrite <- add_opp_r. now rewrite add_comm. Qed. -Theorem Zsub_opp_r : forall n m : Z, n - (- m) == n + m. +Theorem sub_opp_r : forall n m, n - (- m) == n + m. Proof. -intros n m; rewrite <- Zadd_opp_r; now rewrite Zopp_involutive. +intros n m; rewrite <- add_opp_r; now rewrite opp_involutive. Qed. -Theorem Zadd_sub_swap : forall n m p : Z, n + m - p == n - p + m. +Theorem add_sub_swap : forall n m p, n + m - p == n - p + m. Proof. -intros n m p. rewrite <- Zadd_sub_assoc, <- (Zadd_opp_r n p), <- Zadd_assoc. -now rewrite Zadd_opp_l. +intros n m p. rewrite <- add_sub_assoc, <- (add_opp_r n p), <- add_assoc. +now rewrite add_opp_l. Qed. -Theorem Zsub_cancel_l : forall n m p : Z, n - m == n - p <-> m == p. +Theorem sub_cancel_l : forall n m p, n - m == n - p <-> m == p. Proof. -intros n m p. rewrite <- (Zadd_cancel_l (n - m) (n - p) (- n)). -do 2 rewrite Zadd_sub_assoc. rewrite Zadd_opp_diag_l; do 2 rewrite Zsub_0_l. -apply Zopp_inj_wd. +intros n m p. rewrite <- (add_cancel_l (n - m) (n - p) (- n)). +do 2 rewrite add_sub_assoc. rewrite add_opp_diag_l; do 2 rewrite sub_0_l. +apply opp_inj_wd. Qed. -Theorem Zsub_cancel_r : forall n m p : Z, n - p == m - p <-> n == m. +Theorem sub_cancel_r : forall n m p, n - p == m - p <-> n == m. Proof. intros n m p. -stepl (n - p + p == m - p + p) by apply Zadd_cancel_r. -now do 2 rewrite <- Zsub_sub_distr, Zsub_diag, Zsub_0_r. +stepl (n - p + p == m - p + p) by apply add_cancel_r. +now do 2 rewrite <- sub_sub_distr, sub_diag, sub_0_r. Qed. -(* The next several theorems are devoted to moving terms from one side of -an equation to the other. The name contains the operation in the original -equation (add or sub) and the indication whether the left or right term -is moved. *) +(** The next several theorems are devoted to moving terms from one + side of an equation to the other. The name contains the operation + in the original equation ([add] or [sub]) and the indication + whether the left or right term is moved. *) -Theorem Zadd_move_l : forall n m p : Z, n + m == p <-> m == p - n. +Theorem add_move_l : forall n m p, n + m == p <-> m == p - n. Proof. intros n m p. -stepl (n + m - n == p - n) by apply Zsub_cancel_r. -now rewrite Zadd_comm, <- Zadd_sub_assoc, Zsub_diag, Zadd_0_r. +stepl (n + m - n == p - n) by apply sub_cancel_r. +now rewrite add_comm, <- add_sub_assoc, sub_diag, add_0_r. Qed. -Theorem Zadd_move_r : forall n m p : Z, n + m == p <-> n == p - m. +Theorem add_move_r : forall n m p, n + m == p <-> n == p - m. Proof. -intros n m p; rewrite Zadd_comm; now apply Zadd_move_l. +intros n m p; rewrite add_comm; now apply add_move_l. Qed. -(* The two theorems above do not allow rewriting subformulas of the form -n - m == p to n == p + m since subtraction is in the right-hand side of -the equation. Hence the following two theorems. *) +(** The two theorems above do not allow rewriting subformulas of the + form [n - m == p] to [n == p + m] since subtraction is in the + right-hand side of the equation. Hence the following two + theorems. *) -Theorem Zsub_move_l : forall n m p : Z, n - m == p <-> - m == p - n. +Theorem sub_move_l : forall n m p, n - m == p <-> - m == p - n. Proof. -intros n m p; rewrite <- (Zadd_opp_r n m); apply Zadd_move_l. +intros n m p; rewrite <- (add_opp_r n m); apply add_move_l. Qed. -Theorem Zsub_move_r : forall n m p : Z, n - m == p <-> n == p + m. +Theorem sub_move_r : forall n m p, n - m == p <-> n == p + m. Proof. -intros n m p; rewrite <- (Zadd_opp_r n m). now rewrite Zadd_move_r, Zsub_opp_r. +intros n m p; rewrite <- (add_opp_r n m). now rewrite add_move_r, sub_opp_r. Qed. -Theorem Zadd_move_0_l : forall n m : Z, n + m == 0 <-> m == - n. +Theorem add_move_0_l : forall n m, n + m == 0 <-> m == - n. Proof. -intros n m; now rewrite Zadd_move_l, Zsub_0_l. +intros n m; now rewrite add_move_l, sub_0_l. Qed. -Theorem Zadd_move_0_r : forall n m : Z, n + m == 0 <-> n == - m. +Theorem add_move_0_r : forall n m, n + m == 0 <-> n == - m. Proof. -intros n m; now rewrite Zadd_move_r, Zsub_0_l. +intros n m; now rewrite add_move_r, sub_0_l. Qed. -Theorem Zsub_move_0_l : forall n m : Z, n - m == 0 <-> - m == - n. +Theorem sub_move_0_l : forall n m, n - m == 0 <-> - m == - n. Proof. -intros n m. now rewrite Zsub_move_l, Zsub_0_l. +intros n m. now rewrite sub_move_l, sub_0_l. Qed. -Theorem Zsub_move_0_r : forall n m : Z, n - m == 0 <-> n == m. +Theorem sub_move_0_r : forall n m, n - m == 0 <-> n == m. Proof. -intros n m. now rewrite Zsub_move_r, Zadd_0_l. +intros n m. now rewrite sub_move_r, add_0_l. Qed. -(* The following section is devoted to cancellation of like terms. The name -includes the first operator and the position of the term being canceled. *) +(** The following section is devoted to cancellation of like + terms. The name includes the first operator and the position of + the term being canceled. *) -Theorem Zadd_simpl_l : forall n m : Z, n + m - n == m. +Theorem add_simpl_l : forall n m, n + m - n == m. Proof. -intros; now rewrite Zadd_sub_swap, Zsub_diag, Zadd_0_l. +intros; now rewrite add_sub_swap, sub_diag, add_0_l. Qed. -Theorem Zadd_simpl_r : forall n m : Z, n + m - m == n. +Theorem add_simpl_r : forall n m, n + m - m == n. Proof. -intros; now rewrite <- Zadd_sub_assoc, Zsub_diag, Zadd_0_r. +intros; now rewrite <- add_sub_assoc, sub_diag, add_0_r. Qed. -Theorem Zsub_simpl_l : forall n m : Z, - n - m + n == - m. +Theorem sub_simpl_l : forall n m, - n - m + n == - m. Proof. -intros; now rewrite <- Zadd_sub_swap, Zadd_opp_diag_l, Zsub_0_l. +intros; now rewrite <- add_sub_swap, add_opp_diag_l, sub_0_l. Qed. -Theorem Zsub_simpl_r : forall n m : Z, n - m + m == n. +Theorem sub_simpl_r : forall n m, n - m + m == n. Proof. -intros; now rewrite <- Zsub_sub_distr, Zsub_diag, Zsub_0_r. +intros; now rewrite <- sub_sub_distr, sub_diag, sub_0_r. Qed. -(* Now we have two sums or differences; the name includes the two operators -and the position of the terms being canceled *) +(** Now we have two sums or differences; the name includes the two + operators and the position of the terms being canceled *) -Theorem Zadd_add_simpl_l_l : forall n m p : Z, (n + m) - (n + p) == m - p. +Theorem add_add_simpl_l_l : forall n m p, (n + m) - (n + p) == m - p. Proof. -intros n m p. now rewrite (Zadd_comm n m), <- Zadd_sub_assoc, -Zsub_add_distr, Zsub_diag, Zsub_0_l, Zadd_opp_r. +intros n m p. now rewrite (add_comm n m), <- add_sub_assoc, +sub_add_distr, sub_diag, sub_0_l, add_opp_r. Qed. -Theorem Zadd_add_simpl_l_r : forall n m p : Z, (n + m) - (p + n) == m - p. +Theorem add_add_simpl_l_r : forall n m p, (n + m) - (p + n) == m - p. Proof. -intros n m p. rewrite (Zadd_comm p n); apply Zadd_add_simpl_l_l. +intros n m p. rewrite (add_comm p n); apply add_add_simpl_l_l. Qed. -Theorem Zadd_add_simpl_r_l : forall n m p : Z, (n + m) - (m + p) == n - p. +Theorem add_add_simpl_r_l : forall n m p, (n + m) - (m + p) == n - p. Proof. -intros n m p. rewrite (Zadd_comm n m); apply Zadd_add_simpl_l_l. +intros n m p. rewrite (add_comm n m); apply add_add_simpl_l_l. Qed. -Theorem Zadd_add_simpl_r_r : forall n m p : Z, (n + m) - (p + m) == n - p. +Theorem add_add_simpl_r_r : forall n m p, (n + m) - (p + m) == n - p. Proof. -intros n m p. rewrite (Zadd_comm p m); apply Zadd_add_simpl_r_l. +intros n m p. rewrite (add_comm p m); apply add_add_simpl_r_l. Qed. -Theorem Zsub_add_simpl_r_l : forall n m p : Z, (n - m) + (m + p) == n + p. +Theorem sub_add_simpl_r_l : forall n m p, (n - m) + (m + p) == n + p. Proof. -intros n m p. now rewrite <- Zsub_sub_distr, Zsub_add_distr, Zsub_diag, -Zsub_0_l, Zsub_opp_r. +intros n m p. now rewrite <- sub_sub_distr, sub_add_distr, sub_diag, +sub_0_l, sub_opp_r. Qed. -Theorem Zsub_add_simpl_r_r : forall n m p : Z, (n - m) + (p + m) == n + p. +Theorem sub_add_simpl_r_r : forall n m p, (n - m) + (p + m) == n + p. Proof. -intros n m p. rewrite (Zadd_comm p m); apply Zsub_add_simpl_r_l. +intros n m p. rewrite (add_comm p m); apply sub_add_simpl_r_l. Qed. -(* Of course, there are many other variants *) +(** Of course, there are many other variants *) End ZAddPropFunct. diff --git a/theories/Numbers/Integer/Abstract/ZAddOrder.v b/theories/Numbers/Integer/Abstract/ZAddOrder.v index 5f68b2bb1..282709c47 100644 --- a/theories/Numbers/Integer/Abstract/ZAddOrder.v +++ b/theories/Numbers/Integer/Abstract/ZAddOrder.v @@ -12,359 +12,289 @@ Require Export ZLt. -Module ZAddOrderPropFunct (Import ZAxiomsMod : ZAxiomsSig). -Module Export ZOrderPropMod := ZOrderPropFunct ZAxiomsMod. -Open Local Scope IntScope. +Module ZAddOrderPropFunct (Import Z : ZAxiomsSig). +Include ZOrderPropFunct Z. +Local Open Scope NumScope. -(* Theorems that are true on both natural numbers and integers *) +(** Theorems that are either not valid on N or have different proofs + on N and Z *) -Theorem Zadd_lt_mono_l : forall n m p : Z, n < m <-> p + n < p + m. -Proof NZadd_lt_mono_l. - -Theorem Zadd_lt_mono_r : forall n m p : Z, n < m <-> n + p < m + p. -Proof NZadd_lt_mono_r. - -Theorem Zadd_lt_mono : forall n m p q : Z, n < m -> p < q -> n + p < m + q. -Proof NZadd_lt_mono. - -Theorem Zadd_le_mono_l : forall n m p : Z, n <= m <-> p + n <= p + m. -Proof NZadd_le_mono_l. - -Theorem Zadd_le_mono_r : forall n m p : Z, n <= m <-> n + p <= m + p. -Proof NZadd_le_mono_r. - -Theorem Zadd_le_mono : forall n m p q : Z, n <= m -> p <= q -> n + p <= m + q. -Proof NZadd_le_mono. - -Theorem Zadd_lt_le_mono : forall n m p q : Z, n < m -> p <= q -> n + p < m + q. -Proof NZadd_lt_le_mono. - -Theorem Zadd_le_lt_mono : forall n m p q : Z, n <= m -> p < q -> n + p < m + q. -Proof NZadd_le_lt_mono. - -Theorem Zadd_pos_pos : forall n m : Z, 0 < n -> 0 < m -> 0 < n + m. -Proof NZadd_pos_pos. - -Theorem Zadd_pos_nonneg : forall n m : Z, 0 < n -> 0 <= m -> 0 < n + m. -Proof NZadd_pos_nonneg. - -Theorem Zadd_nonneg_pos : forall n m : Z, 0 <= n -> 0 < m -> 0 < n + m. -Proof NZadd_nonneg_pos. - -Theorem Zadd_nonneg_nonneg : forall n m : Z, 0 <= n -> 0 <= m -> 0 <= n + m. -Proof NZadd_nonneg_nonneg. - -Theorem Zlt_add_pos_l : forall n m : Z, 0 < n -> m < n + m. -Proof NZlt_add_pos_l. - -Theorem Zlt_add_pos_r : forall n m : Z, 0 < n -> m < m + n. -Proof NZlt_add_pos_r. - -Theorem Zle_lt_add_lt : forall n m p q : Z, n <= m -> p + m < q + n -> p < q. -Proof NZle_lt_add_lt. - -Theorem Zlt_le_add_lt : forall n m p q : Z, n < m -> p + m <= q + n -> p < q. -Proof NZlt_le_add_lt. - -Theorem Zle_le_add_le : forall n m p q : Z, n <= m -> p + m <= q + n -> p <= q. -Proof NZle_le_add_le. - -Theorem Zadd_lt_cases : forall n m p q : Z, n + m < p + q -> n < p \/ m < q. -Proof NZadd_lt_cases. - -Theorem Zadd_le_cases : forall n m p q : Z, n + m <= p + q -> n <= p \/ m <= q. -Proof NZadd_le_cases. - -Theorem Zadd_neg_cases : forall n m : Z, n + m < 0 -> n < 0 \/ m < 0. -Proof NZadd_neg_cases. - -Theorem Zadd_pos_cases : forall n m : Z, 0 < n + m -> 0 < n \/ 0 < m. -Proof NZadd_pos_cases. - -Theorem Zadd_nonpos_cases : forall n m : Z, n + m <= 0 -> n <= 0 \/ m <= 0. -Proof NZadd_nonpos_cases. - -Theorem Zadd_nonneg_cases : forall n m : Z, 0 <= n + m -> 0 <= n \/ 0 <= m. -Proof NZadd_nonneg_cases. - -(* Theorems that are either not valid on N or have different proofs on N and Z *) - -Theorem Zadd_neg_neg : forall n m : Z, n < 0 -> m < 0 -> n + m < 0. +Theorem add_neg_neg : forall n m, n < 0 -> m < 0 -> n + m < 0. Proof. -intros n m H1 H2. rewrite <- (Zadd_0_l 0). now apply Zadd_lt_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_lt_mono. Qed. -Theorem Zadd_neg_nonpos : forall n m : Z, n < 0 -> m <= 0 -> n + m < 0. +Theorem add_neg_nonpos : forall n m, n < 0 -> m <= 0 -> n + m < 0. Proof. -intros n m H1 H2. rewrite <- (Zadd_0_l 0). now apply Zadd_lt_le_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_lt_le_mono. Qed. -Theorem Zadd_nonpos_neg : forall n m : Z, n <= 0 -> m < 0 -> n + m < 0. +Theorem add_nonpos_neg : forall n m, n <= 0 -> m < 0 -> n + m < 0. Proof. -intros n m H1 H2. rewrite <- (Zadd_0_l 0). now apply Zadd_le_lt_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_le_lt_mono. Qed. -Theorem Zadd_nonpos_nonpos : forall n m : Z, n <= 0 -> m <= 0 -> n + m <= 0. +Theorem add_nonpos_nonpos : forall n m, n <= 0 -> m <= 0 -> n + m <= 0. Proof. -intros n m H1 H2. rewrite <- (Zadd_0_l 0). now apply Zadd_le_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_le_mono. Qed. (** Sub and order *) -Theorem Zlt_0_sub : forall n m : Z, 0 < m - n <-> n < m. +Theorem lt_0_sub : forall n m, 0 < m - n <-> n < m. Proof. -intros n m. stepl (0 + n < m - n + n) by symmetry; apply Zadd_lt_mono_r. -rewrite Zadd_0_l; now rewrite Zsub_simpl_r. +intros n m. stepl (0 + n < m - n + n) by symmetry; apply add_lt_mono_r. +rewrite add_0_l; now rewrite sub_simpl_r. Qed. -Notation Zsub_pos := Zlt_0_sub (only parsing). +Notation sub_pos := lt_0_sub (only parsing). -Theorem Zle_0_sub : forall n m : Z, 0 <= m - n <-> n <= m. +Theorem le_0_sub : forall n m, 0 <= m - n <-> n <= m. Proof. -intros n m; stepl (0 + n <= m - n + n) by symmetry; apply Zadd_le_mono_r. -rewrite Zadd_0_l; now rewrite Zsub_simpl_r. +intros n m; stepl (0 + n <= m - n + n) by symmetry; apply add_le_mono_r. +rewrite add_0_l; now rewrite sub_simpl_r. Qed. -Notation Zsub_nonneg := Zle_0_sub (only parsing). +Notation sub_nonneg := le_0_sub (only parsing). -Theorem Zlt_sub_0 : forall n m : Z, n - m < 0 <-> n < m. +Theorem lt_sub_0 : forall n m, n - m < 0 <-> n < m. Proof. -intros n m. stepl (n - m + m < 0 + m) by symmetry; apply Zadd_lt_mono_r. -rewrite Zadd_0_l; now rewrite Zsub_simpl_r. +intros n m. stepl (n - m + m < 0 + m) by symmetry; apply add_lt_mono_r. +rewrite add_0_l; now rewrite sub_simpl_r. Qed. -Notation Zsub_neg := Zlt_sub_0 (only parsing). +Notation sub_neg := lt_sub_0 (only parsing). -Theorem Zle_sub_0 : forall n m : Z, n - m <= 0 <-> n <= m. +Theorem le_sub_0 : forall n m, n - m <= 0 <-> n <= m. Proof. -intros n m. stepl (n - m + m <= 0 + m) by symmetry; apply Zadd_le_mono_r. -rewrite Zadd_0_l; now rewrite Zsub_simpl_r. +intros n m. stepl (n - m + m <= 0 + m) by symmetry; apply add_le_mono_r. +rewrite add_0_l; now rewrite sub_simpl_r. Qed. -Notation Zsub_nonpos := Zle_sub_0 (only parsing). +Notation sub_nonpos := le_sub_0 (only parsing). -Theorem Zopp_lt_mono : forall n m : Z, n < m <-> - m < - n. +Theorem opp_lt_mono : forall n m, n < m <-> - m < - n. Proof. -intros n m. stepr (m + - m < m + - n) by symmetry; apply Zadd_lt_mono_l. -do 2 rewrite Zadd_opp_r. rewrite Zsub_diag. symmetry; apply Zlt_0_sub. +intros n m. stepr (m + - m < m + - n) by symmetry; apply add_lt_mono_l. +do 2 rewrite add_opp_r. rewrite sub_diag. symmetry; apply lt_0_sub. Qed. -Theorem Zopp_le_mono : forall n m : Z, n <= m <-> - m <= - n. +Theorem opp_le_mono : forall n m, n <= m <-> - m <= - n. Proof. -intros n m. stepr (m + - m <= m + - n) by symmetry; apply Zadd_le_mono_l. -do 2 rewrite Zadd_opp_r. rewrite Zsub_diag. symmetry; apply Zle_0_sub. +intros n m. stepr (m + - m <= m + - n) by symmetry; apply add_le_mono_l. +do 2 rewrite add_opp_r. rewrite sub_diag. symmetry; apply le_0_sub. Qed. -Theorem Zopp_pos_neg : forall n : Z, 0 < - n <-> n < 0. +Theorem opp_pos_neg : forall n, 0 < - n <-> n < 0. Proof. -intro n; rewrite (Zopp_lt_mono n 0); now rewrite Zopp_0. +intro n; rewrite (opp_lt_mono n 0); now rewrite opp_0. Qed. -Theorem Zopp_neg_pos : forall n : Z, - n < 0 <-> 0 < n. +Theorem opp_neg_pos : forall n, - n < 0 <-> 0 < n. Proof. -intro n. rewrite (Zopp_lt_mono 0 n). now rewrite Zopp_0. +intro n. rewrite (opp_lt_mono 0 n). now rewrite opp_0. Qed. -Theorem Zopp_nonneg_nonpos : forall n : Z, 0 <= - n <-> n <= 0. +Theorem opp_nonneg_nonpos : forall n, 0 <= - n <-> n <= 0. Proof. -intro n; rewrite (Zopp_le_mono n 0); now rewrite Zopp_0. +intro n; rewrite (opp_le_mono n 0); now rewrite opp_0. Qed. -Theorem Zopp_nonpos_nonneg : forall n : Z, - n <= 0 <-> 0 <= n. +Theorem opp_nonpos_nonneg : forall n, - n <= 0 <-> 0 <= n. Proof. -intro n. rewrite (Zopp_le_mono 0 n). now rewrite Zopp_0. +intro n. rewrite (opp_le_mono 0 n). now rewrite opp_0. Qed. -Theorem Zsub_lt_mono_l : forall n m p : Z, n < m <-> p - m < p - n. +Theorem sub_lt_mono_l : forall n m p, n < m <-> p - m < p - n. Proof. -intros n m p. do 2 rewrite <- Zadd_opp_r. rewrite <- Zadd_lt_mono_l. -apply Zopp_lt_mono. +intros n m p. do 2 rewrite <- add_opp_r. rewrite <- add_lt_mono_l. +apply opp_lt_mono. Qed. -Theorem Zsub_lt_mono_r : forall n m p : Z, n < m <-> n - p < m - p. +Theorem sub_lt_mono_r : forall n m p, n < m <-> n - p < m - p. Proof. -intros n m p; do 2 rewrite <- Zadd_opp_r; apply Zadd_lt_mono_r. +intros n m p; do 2 rewrite <- add_opp_r; apply add_lt_mono_r. Qed. -Theorem Zsub_lt_mono : forall n m p q : Z, n < m -> q < p -> n - p < m - q. +Theorem sub_lt_mono : forall n m p q, n < m -> q < p -> n - p < m - q. Proof. intros n m p q H1 H2. -apply NZlt_trans with (m - p); -[now apply -> Zsub_lt_mono_r | now apply -> Zsub_lt_mono_l]. +apply lt_trans with (m - p); +[now apply -> sub_lt_mono_r | now apply -> sub_lt_mono_l]. Qed. -Theorem Zsub_le_mono_l : forall n m p : Z, n <= m <-> p - m <= p - n. +Theorem sub_le_mono_l : forall n m p, n <= m <-> p - m <= p - n. Proof. -intros n m p; do 2 rewrite <- Zadd_opp_r; rewrite <- Zadd_le_mono_l; -apply Zopp_le_mono. +intros n m p; do 2 rewrite <- add_opp_r; rewrite <- add_le_mono_l; +apply opp_le_mono. Qed. -Theorem Zsub_le_mono_r : forall n m p : Z, n <= m <-> n - p <= m - p. +Theorem sub_le_mono_r : forall n m p, n <= m <-> n - p <= m - p. Proof. -intros n m p; do 2 rewrite <- Zadd_opp_r; apply Zadd_le_mono_r. +intros n m p; do 2 rewrite <- add_opp_r; apply add_le_mono_r. Qed. -Theorem Zsub_le_mono : forall n m p q : Z, n <= m -> q <= p -> n - p <= m - q. +Theorem sub_le_mono : forall n m p q, n <= m -> q <= p -> n - p <= m - q. Proof. intros n m p q H1 H2. -apply NZle_trans with (m - p); -[now apply -> Zsub_le_mono_r | now apply -> Zsub_le_mono_l]. +apply le_trans with (m - p); +[now apply -> sub_le_mono_r | now apply -> sub_le_mono_l]. Qed. -Theorem Zsub_lt_le_mono : forall n m p q : Z, n < m -> q <= p -> n - p < m - q. +Theorem sub_lt_le_mono : forall n m p q, n < m -> q <= p -> n - p < m - q. Proof. intros n m p q H1 H2. -apply NZlt_le_trans with (m - p); -[now apply -> Zsub_lt_mono_r | now apply -> Zsub_le_mono_l]. +apply lt_le_trans with (m - p); +[now apply -> sub_lt_mono_r | now apply -> sub_le_mono_l]. Qed. -Theorem Zsub_le_lt_mono : forall n m p q : Z, n <= m -> q < p -> n - p < m - q. +Theorem sub_le_lt_mono : forall n m p q, n <= m -> q < p -> n - p < m - q. Proof. intros n m p q H1 H2. -apply NZle_lt_trans with (m - p); -[now apply -> Zsub_le_mono_r | now apply -> Zsub_lt_mono_l]. +apply le_lt_trans with (m - p); +[now apply -> sub_le_mono_r | now apply -> sub_lt_mono_l]. Qed. -Theorem Zle_lt_sub_lt : forall n m p q : Z, n <= m -> p - n < q - m -> p < q. +Theorem le_lt_sub_lt : forall n m p q, n <= m -> p - n < q - m -> p < q. Proof. -intros n m p q H1 H2. apply (Zle_lt_add_lt (- m) (- n)); -[now apply -> Zopp_le_mono | now do 2 rewrite Zadd_opp_r]. +intros n m p q H1 H2. apply (le_lt_add_lt (- m) (- n)); +[now apply -> opp_le_mono | now do 2 rewrite add_opp_r]. Qed. -Theorem Zlt_le_sub_lt : forall n m p q : Z, n < m -> p - n <= q - m -> p < q. +Theorem lt_le_sub_lt : forall n m p q, n < m -> p - n <= q - m -> p < q. Proof. -intros n m p q H1 H2. apply (Zlt_le_add_lt (- m) (- n)); -[now apply -> Zopp_lt_mono | now do 2 rewrite Zadd_opp_r]. +intros n m p q H1 H2. apply (lt_le_add_lt (- m) (- n)); +[now apply -> opp_lt_mono | now do 2 rewrite add_opp_r]. Qed. -Theorem Zle_le_sub_lt : forall n m p q : Z, n <= m -> p - n <= q - m -> p <= q. +Theorem le_le_sub_lt : forall n m p q, n <= m -> p - n <= q - m -> p <= q. Proof. -intros n m p q H1 H2. apply (Zle_le_add_le (- m) (- n)); -[now apply -> Zopp_le_mono | now do 2 rewrite Zadd_opp_r]. +intros n m p q H1 H2. apply (le_le_add_le (- m) (- n)); +[now apply -> opp_le_mono | now do 2 rewrite add_opp_r]. Qed. -Theorem Zlt_add_lt_sub_r : forall n m p : Z, n + p < m <-> n < m - p. +Theorem lt_add_lt_sub_r : forall n m p, n + p < m <-> n < m - p. Proof. -intros n m p. stepl (n + p - p < m - p) by symmetry; apply Zsub_lt_mono_r. -now rewrite Zadd_simpl_r. +intros n m p. stepl (n + p - p < m - p) by symmetry; apply sub_lt_mono_r. +now rewrite add_simpl_r. Qed. -Theorem Zle_add_le_sub_r : forall n m p : Z, n + p <= m <-> n <= m - p. +Theorem le_add_le_sub_r : forall n m p, n + p <= m <-> n <= m - p. Proof. -intros n m p. stepl (n + p - p <= m - p) by symmetry; apply Zsub_le_mono_r. -now rewrite Zadd_simpl_r. +intros n m p. stepl (n + p - p <= m - p) by symmetry; apply sub_le_mono_r. +now rewrite add_simpl_r. Qed. -Theorem Zlt_add_lt_sub_l : forall n m p : Z, n + p < m <-> p < m - n. +Theorem lt_add_lt_sub_l : forall n m p, n + p < m <-> p < m - n. Proof. -intros n m p. rewrite Zadd_comm; apply Zlt_add_lt_sub_r. +intros n m p. rewrite add_comm; apply lt_add_lt_sub_r. Qed. -Theorem Zle_add_le_sub_l : forall n m p : Z, n + p <= m <-> p <= m - n. +Theorem le_add_le_sub_l : forall n m p, n + p <= m <-> p <= m - n. Proof. -intros n m p. rewrite Zadd_comm; apply Zle_add_le_sub_r. +intros n m p. rewrite add_comm; apply le_add_le_sub_r. Qed. -Theorem Zlt_sub_lt_add_r : forall n m p : Z, n - p < m <-> n < m + p. +Theorem lt_sub_lt_add_r : forall n m p, n - p < m <-> n < m + p. Proof. -intros n m p. stepl (n - p + p < m + p) by symmetry; apply Zadd_lt_mono_r. -now rewrite Zsub_simpl_r. +intros n m p. stepl (n - p + p < m + p) by symmetry; apply add_lt_mono_r. +now rewrite sub_simpl_r. Qed. -Theorem Zle_sub_le_add_r : forall n m p : Z, n - p <= m <-> n <= m + p. +Theorem le_sub_le_add_r : forall n m p, n - p <= m <-> n <= m + p. Proof. -intros n m p. stepl (n - p + p <= m + p) by symmetry; apply Zadd_le_mono_r. -now rewrite Zsub_simpl_r. +intros n m p. stepl (n - p + p <= m + p) by symmetry; apply add_le_mono_r. +now rewrite sub_simpl_r. Qed. -Theorem Zlt_sub_lt_add_l : forall n m p : Z, n - m < p <-> n < m + p. +Theorem lt_sub_lt_add_l : forall n m p, n - m < p <-> n < m + p. Proof. -intros n m p. rewrite Zadd_comm; apply Zlt_sub_lt_add_r. +intros n m p. rewrite add_comm; apply lt_sub_lt_add_r. Qed. -Theorem Zle_sub_le_add_l : forall n m p : Z, n - m <= p <-> n <= m + p. +Theorem le_sub_le_add_l : forall n m p, n - m <= p <-> n <= m + p. Proof. -intros n m p. rewrite Zadd_comm; apply Zle_sub_le_add_r. +intros n m p. rewrite add_comm; apply le_sub_le_add_r. Qed. -Theorem Zlt_sub_lt_add : forall n m p q : Z, n - m < p - q <-> n + q < m + p. +Theorem lt_sub_lt_add : forall n m p q, n - m < p - q <-> n + q < m + p. Proof. -intros n m p q. rewrite Zlt_sub_lt_add_l. rewrite Zadd_sub_assoc. -now rewrite <- Zlt_add_lt_sub_r. +intros n m p q. rewrite lt_sub_lt_add_l. rewrite add_sub_assoc. +now rewrite <- lt_add_lt_sub_r. Qed. -Theorem Zle_sub_le_add : forall n m p q : Z, n - m <= p - q <-> n + q <= m + p. +Theorem le_sub_le_add : forall n m p q, n - m <= p - q <-> n + q <= m + p. Proof. -intros n m p q. rewrite Zle_sub_le_add_l. rewrite Zadd_sub_assoc. -now rewrite <- Zle_add_le_sub_r. +intros n m p q. rewrite le_sub_le_add_l. rewrite add_sub_assoc. +now rewrite <- le_add_le_sub_r. Qed. -Theorem Zlt_sub_pos : forall n m : Z, 0 < m <-> n - m < n. +Theorem lt_sub_pos : forall n m, 0 < m <-> n - m < n. Proof. -intros n m. stepr (n - m < n - 0) by now rewrite Zsub_0_r. apply Zsub_lt_mono_l. +intros n m. stepr (n - m < n - 0) by now rewrite sub_0_r. apply sub_lt_mono_l. Qed. -Theorem Zle_sub_nonneg : forall n m : Z, 0 <= m <-> n - m <= n. +Theorem le_sub_nonneg : forall n m, 0 <= m <-> n - m <= n. Proof. -intros n m. stepr (n - m <= n - 0) by now rewrite Zsub_0_r. apply Zsub_le_mono_l. +intros n m. stepr (n - m <= n - 0) by now rewrite sub_0_r. apply sub_le_mono_l. Qed. -Theorem Zsub_lt_cases : forall n m p q : Z, n - m < p - q -> n < m \/ q < p. +Theorem sub_lt_cases : forall n m p q, n - m < p - q -> n < m \/ q < p. Proof. -intros n m p q H. rewrite Zlt_sub_lt_add in H. now apply Zadd_lt_cases. +intros n m p q H. rewrite lt_sub_lt_add in H. now apply add_lt_cases. Qed. -Theorem Zsub_le_cases : forall n m p q : Z, n - m <= p - q -> n <= m \/ q <= p. +Theorem sub_le_cases : forall n m p q, n - m <= p - q -> n <= m \/ q <= p. Proof. -intros n m p q H. rewrite Zle_sub_le_add in H. now apply Zadd_le_cases. +intros n m p q H. rewrite le_sub_le_add in H. now apply add_le_cases. Qed. -Theorem Zsub_neg_cases : forall n m : Z, n - m < 0 -> n < 0 \/ 0 < m. +Theorem sub_neg_cases : forall n m, n - m < 0 -> n < 0 \/ 0 < m. Proof. -intros n m H; rewrite <- Zadd_opp_r in H. -setoid_replace (0 < m) with (- m < 0) using relation iff by (symmetry; apply Zopp_neg_pos). -now apply Zadd_neg_cases. +intros n m H; rewrite <- add_opp_r in H. +setoid_replace (0 < m) with (- m < 0) using relation iff by (symmetry; apply opp_neg_pos). +now apply add_neg_cases. Qed. -Theorem Zsub_pos_cases : forall n m : Z, 0 < n - m -> 0 < n \/ m < 0. +Theorem sub_pos_cases : forall n m, 0 < n - m -> 0 < n \/ m < 0. Proof. -intros n m H; rewrite <- Zadd_opp_r in H. -setoid_replace (m < 0) with (0 < - m) using relation iff by (symmetry; apply Zopp_pos_neg). -now apply Zadd_pos_cases. +intros n m H; rewrite <- add_opp_r in H. +setoid_replace (m < 0) with (0 < - m) using relation iff by (symmetry; apply opp_pos_neg). +now apply add_pos_cases. Qed. -Theorem Zsub_nonpos_cases : forall n m : Z, n - m <= 0 -> n <= 0 \/ 0 <= m. +Theorem sub_nonpos_cases : forall n m, n - m <= 0 -> n <= 0 \/ 0 <= m. Proof. -intros n m H; rewrite <- Zadd_opp_r in H. -setoid_replace (0 <= m) with (- m <= 0) using relation iff by (symmetry; apply Zopp_nonpos_nonneg). -now apply Zadd_nonpos_cases. +intros n m H; rewrite <- add_opp_r in H. +setoid_replace (0 <= m) with (- m <= 0) using relation iff by (symmetry; apply opp_nonpos_nonneg). +now apply add_nonpos_cases. Qed. -Theorem Zsub_nonneg_cases : forall n m : Z, 0 <= n - m -> 0 <= n \/ m <= 0. +Theorem sub_nonneg_cases : forall n m, 0 <= n - m -> 0 <= n \/ m <= 0. Proof. -intros n m H; rewrite <- Zadd_opp_r in H. -setoid_replace (m <= 0) with (0 <= - m) using relation iff by (symmetry; apply Zopp_nonneg_nonpos). -now apply Zadd_nonneg_cases. +intros n m H; rewrite <- add_opp_r in H. +setoid_replace (m <= 0) with (0 <= - m) using relation iff by (symmetry; apply opp_nonneg_nonpos). +now apply add_nonneg_cases. Qed. Section PosNeg. -Variable P : Z -> Prop. -Hypothesis P_wd : Proper (Zeq ==> iff) P. +Variable P : Z.t -> Prop. +Hypothesis P_wd : Proper (Z.eq ==> iff) P. -Theorem Z0_pos_neg : - P 0 -> (forall n : Z, 0 < n -> P n /\ P (- n)) -> forall n : Z, P n. +Theorem zero_pos_neg : + P 0 -> (forall n, 0 < n -> P n /\ P (- n)) -> forall n, P n. Proof. -intros H1 H2 n. destruct (Zlt_trichotomy n 0) as [H3 | [H3 | H3]]. -apply <- Zopp_pos_neg in H3. apply H2 in H3. destruct H3 as [_ H3]. -now rewrite Zopp_involutive in H3. +intros H1 H2 n. destruct (lt_trichotomy n 0) as [H3 | [H3 | H3]]. +apply <- opp_pos_neg in H3. apply H2 in H3. destruct H3 as [_ H3]. +now rewrite opp_involutive in H3. now rewrite H3. apply H2 in H3; now destruct H3. Qed. End PosNeg. -Ltac Z0_pos_neg n := induction_maker n ltac:(apply Z0_pos_neg). +Ltac zero_pos_neg n := induction_maker n ltac:(apply zero_pos_neg). End ZAddOrderPropFunct. diff --git a/theories/Numbers/Integer/Abstract/ZAxioms.v b/theories/Numbers/Integer/Abstract/ZAxioms.v index bd6db10d9..4acb45401 100644 --- a/theories/Numbers/Integer/Abstract/ZAxioms.v +++ b/theories/Numbers/Integer/Abstract/ZAxioms.v @@ -15,51 +15,21 @@ Require Export NZAxioms. Set Implicit Arguments. Module Type ZAxiomsSig. -Declare Module Export NZOrdAxiomsMod : NZOrdAxiomsSig. +Include Type NZOrdAxiomsSig. +Local Open Scope NumScope. -Delimit Scope IntScope with Int. -Notation Z := NZ. -Notation Zeq := NZeq. -Notation Z0 := NZ0. -Notation Z1 := (NZsucc NZ0). -Notation S := NZsucc. -Notation P := NZpred. -Notation Zadd := NZadd. -Notation Zmul := NZmul. -Notation Zsub := NZsub. -Notation Zlt := NZlt. -Notation Zle := NZle. -Notation Zmin := NZmin. -Notation Zmax := NZmax. -Notation "x == y" := (NZeq x y) (at level 70) : IntScope. -Notation "x ~= y" := (~ NZeq x y) (at level 70) : IntScope. -Notation "0" := NZ0 : IntScope. -Notation "1" := (NZsucc NZ0) : IntScope. -Notation "x + y" := (NZadd x y) : IntScope. -Notation "x - y" := (NZsub x y) : IntScope. -Notation "x * y" := (NZmul x y) : IntScope. -Notation "x < y" := (NZlt x y) : IntScope. -Notation "x <= y" := (NZle x y) : IntScope. -Notation "x > y" := (NZlt y x) (only parsing) : IntScope. -Notation "x >= y" := (NZle y x) (only parsing) : IntScope. +Parameter Inline opp : t -> t. +Instance opp_wd : Proper (eq==>eq) opp. -Parameter Zopp : Z -> Z. - -(*Notation "- 1" := (Zopp 1) : IntScope. -Check (-1).*) - -Instance Zopp_wd : Proper (Zeq==>Zeq) Zopp. - -Notation "- x" := (Zopp x) (at level 35, right associativity) : IntScope. -Notation "- 1" := (Zopp (NZsucc NZ0)) : IntScope. - -Open Local Scope IntScope. +Notation "- x" := (opp x) (at level 35, right associativity) : NumScope. +Notation "- 1" := (- (1)) : NumScope. (* Integers are obtained by postulating that every number has a predecessor *) -Axiom Zsucc_pred : forall n : Z, S (P n) == n. -Axiom Zopp_0 : - 0 == 0. -Axiom Zopp_succ : forall n : Z, - (S n) == P (- n). +Axiom succ_pred : forall n, S (P n) == n. + +Axiom opp_0 : - 0 == 0. +Axiom opp_succ : forall n, - (S n) == P (- n). End ZAxiomsSig. diff --git a/theories/Numbers/Integer/Abstract/ZBase.v b/theories/Numbers/Integer/Abstract/ZBase.v index 00e34a5b5..3429a4fa3 100644 --- a/theories/Numbers/Integer/Abstract/ZBase.v +++ b/theories/Numbers/Integer/Abstract/ZBase.v @@ -12,74 +12,22 @@ Require Export Decidable. Require Export ZAxioms. -Require Import NZMulOrder. +Require Import NZProperties. -Module ZBasePropFunct (Import ZAxiomsMod : ZAxiomsSig). - -(* Note: writing "Export" instead of "Import" on the previous line leads to -some warnings about hiding repeated declarations and results in the loss of -notations in Zadd and later *) - -Open Local Scope IntScope. - -Module Export NZMulOrderMod := NZMulOrderPropFunct NZOrdAxiomsMod. - -Theorem Zsucc_wd : forall n1 n2 : Z, n1 == n2 -> S n1 == S n2. -Proof NZsucc_wd. - -Theorem Zpred_wd : forall n1 n2 : Z, n1 == n2 -> P n1 == P n2. -Proof NZpred_wd. - -Theorem Zpred_succ : forall n : Z, P (S n) == n. -Proof NZpred_succ. - -Theorem Zeq_refl : forall n : Z, n == n. -Proof (@Equivalence_Reflexive _ _ NZeq_equiv). - -Theorem Zeq_sym : forall n m : Z, n == m -> m == n. -Proof (@Equivalence_Symmetric _ _ NZeq_equiv). - -Theorem Zeq_trans : forall n m p : Z, n == m -> m == p -> n == p. -Proof (@Equivalence_Transitive _ _ NZeq_equiv). - -Theorem Zneq_sym : forall n m : Z, n ~= m -> m ~= n. -Proof NZneq_sym. - -Theorem Zsucc_inj : forall n1 n2 : Z, S n1 == S n2 -> n1 == n2. -Proof NZsucc_inj. - -Theorem Zsucc_inj_wd : forall n1 n2 : Z, S n1 == S n2 <-> n1 == n2. -Proof NZsucc_inj_wd. - -Theorem Zsucc_inj_wd_neg : forall n m : Z, S n ~= S m <-> n ~= m. -Proof NZsucc_inj_wd_neg. - -(* Decidability and stability of equality was proved only in NZOrder, but -since it does not mention order, we'll put it here *) - -Theorem Zeq_dec : forall n m : Z, decidable (n == m). -Proof NZeq_dec. - -Theorem Zeq_dne : forall n m : Z, ~ ~ n == m <-> n == m. -Proof NZeq_dne. - -Theorem Zcentral_induction : -forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, A z -> - (forall n : Z, A n <-> A (S n)) -> - forall n : Z, A n. -Proof NZcentral_induction. +Module ZBasePropFunct (Import Z : ZAxiomsSig). +Include NZPropFunct Z. +Local Open Scope NumScope. (* Theorems that are true for integers but not for natural numbers *) -Theorem Zpred_inj : forall n m : Z, P n == P m -> n == m. +Theorem pred_inj : forall n m, P n == P m -> n == m. Proof. -intros n m H. apply NZsucc_wd in H. now do 2 rewrite Zsucc_pred in H. +intros n m H. apply succ_wd in H. now do 2 rewrite succ_pred in H. Qed. -Theorem Zpred_inj_wd : forall n1 n2 : Z, P n1 == P n2 <-> n1 == n2. +Theorem pred_inj_wd : forall n1 n2, P n1 == P n2 <-> n1 == n2. Proof. -intros n1 n2; split; [apply Zpred_inj | apply NZpred_wd]. +intros n1 n2; split; [apply pred_inj | apply pred_wd]. Qed. End ZBasePropFunct. diff --git a/theories/Numbers/Integer/Abstract/ZDomain.v b/theories/Numbers/Integer/Abstract/ZDomain.v deleted file mode 100644 index 500dd9f53..000000000 --- a/theories/Numbers/Integer/Abstract/ZDomain.v +++ /dev/null @@ -1,59 +0,0 @@ -(************************************************************************) -(* v * The Coq Proof Assistant / The Coq Development Team *) -(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) -(* \VV/ **************************************************************) -(* // * This file is distributed under the terms of the *) -(* * GNU Lesser General Public License Version 2.1 *) -(************************************************************************) -(* Evgeny Makarov, INRIA, 2007 *) -(************************************************************************) - -(*i $Id$ i*) - -Require Import Bool. -Require Export NumPrelude. - -Module Type ZDomainSignature. - -Parameter Inline Z : Set. -Parameter Inline Zeq : Z -> Z -> Prop. -Parameter Inline Zeqb : Z -> Z -> bool. - -Axiom eqb_equiv_eq : forall x y : Z, Zeqb x y = true <-> Zeq x y. -Instance eq_equiv : Equivalence Zeq. - -Delimit Scope IntScope with Int. -Bind Scope IntScope with Z. -Notation "x == y" := (Zeq x y) (at level 70) : IntScope. -Notation "x # y" := (~ Zeq x y) (at level 70) : IntScope. - -End ZDomainSignature. - -Module ZDomainProperties (Import ZDomainModule : ZDomainSignature). -Open Local Scope IntScope. - -Instance Zeqb_wd : Proper (Zeq ==> Zeq ==> eq) Zeqb. -Proof. -intros x x' Exx' y y' Eyy'. -apply eq_true_iff_eq. -rewrite 2 eqb_equiv_eq, Exx', Eyy'; auto with *. -Qed. - -Theorem neq_sym : forall n m, n # m -> m # n. -Proof. -intros n m H1 H2; symmetry in H2; false_hyp H2 H1. -Qed. - -Theorem ZE_stepl : forall x y z : Z, x == y -> x == z -> z == y. -Proof. -intros x y z H1 H2; now rewrite <- H1. -Qed. - -Declare Left Step ZE_stepl. - -(* The right step lemma is just transitivity of Zeq *) -Declare Right Step (@Equivalence_Transitive _ _ eq_equiv). - -End ZDomainProperties. - - diff --git a/theories/Numbers/Integer/Abstract/ZLt.v b/theories/Numbers/Integer/Abstract/ZLt.v index efd1f0da3..e77f9c453 100644 --- a/theories/Numbers/Integer/Abstract/ZLt.v +++ b/theories/Numbers/Integer/Abstract/ZLt.v @@ -12,420 +12,123 @@ Require Export ZMul. -Module ZOrderPropFunct (Import ZAxiomsMod : ZAxiomsSig). -Module Export ZMulPropMod := ZMulPropFunct ZAxiomsMod. -Open Local Scope IntScope. +Module ZOrderPropFunct (Import Z : ZAxiomsSig). +Include ZMulPropFunct Z. +Local Open Scope NumScope. -(* Axioms *) +(** Instances of earlier theorems for m == 0 *) -Theorem Zlt_wd : - forall n1 n2 : Z, n1 == n2 -> forall m1 m2 : Z, m1 == m2 -> (n1 < m1 <-> n2 < m2). -Proof NZlt_wd. - -Theorem Zle_wd : - forall n1 n2 : Z, n1 == n2 -> forall m1 m2 : Z, m1 == m2 -> (n1 <= m1 <-> n2 <= m2). -Proof NZle_wd. - -Theorem Zmin_wd : - forall n1 n2 : Z, n1 == n2 -> forall m1 m2 : Z, m1 == m2 -> Zmin n1 m1 == Zmin n2 m2. -Proof NZmin_wd. - -Theorem Zmax_wd : - forall n1 n2 : Z, n1 == n2 -> forall m1 m2 : Z, m1 == m2 -> Zmax n1 m1 == Zmax n2 m2. -Proof NZmax_wd. - -Theorem Zlt_eq_cases : forall n m : Z, n <= m <-> n < m \/ n == m. -Proof NZlt_eq_cases. - -Theorem Zlt_irrefl : forall n : Z, ~ n < n. -Proof NZlt_irrefl. - -Theorem Zlt_succ_r : forall n m : Z, n < S m <-> n <= m. -Proof NZlt_succ_r. - -Theorem Zmin_l : forall n m : Z, n <= m -> Zmin n m == n. -Proof NZmin_l. - -Theorem Zmin_r : forall n m : Z, m <= n -> Zmin n m == m. -Proof NZmin_r. - -Theorem Zmax_l : forall n m : Z, m <= n -> Zmax n m == n. -Proof NZmax_l. - -Theorem Zmax_r : forall n m : Z, n <= m -> Zmax n m == m. -Proof NZmax_r. - -(* Renaming theorems from NZOrder.v *) - -Theorem Zlt_le_incl : forall n m : Z, n < m -> n <= m. -Proof NZlt_le_incl. - -Theorem Zlt_neq : forall n m : Z, n < m -> n ~= m. -Proof NZlt_neq. - -Theorem Zle_neq : forall n m : Z, n < m <-> n <= m /\ n ~= m. -Proof NZle_neq. - -Theorem Zle_refl : forall n : Z, n <= n. -Proof NZle_refl. - -Theorem Zlt_succ_diag_r : forall n : Z, n < S n. -Proof NZlt_succ_diag_r. - -Theorem Zle_succ_diag_r : forall n : Z, n <= S n. -Proof NZle_succ_diag_r. - -Theorem Zlt_0_1 : 0 < 1. -Proof NZlt_0_1. - -Theorem Zle_0_1 : 0 <= 1. -Proof NZle_0_1. - -Theorem Zlt_lt_succ_r : forall n m : Z, n < m -> n < S m. -Proof NZlt_lt_succ_r. - -Theorem Zle_le_succ_r : forall n m : Z, n <= m -> n <= S m. -Proof NZle_le_succ_r. - -Theorem Zle_succ_r : forall n m : Z, n <= S m <-> n <= m \/ n == S m. -Proof NZle_succ_r. - -Theorem Zneq_succ_diag_l : forall n : Z, S n ~= n. -Proof NZneq_succ_diag_l. - -Theorem Zneq_succ_diag_r : forall n : Z, n ~= S n. -Proof NZneq_succ_diag_r. - -Theorem Znlt_succ_diag_l : forall n : Z, ~ S n < n. -Proof NZnlt_succ_diag_l. - -Theorem Znle_succ_diag_l : forall n : Z, ~ S n <= n. -Proof NZnle_succ_diag_l. - -Theorem Zle_succ_l : forall n m : Z, S n <= m <-> n < m. -Proof NZle_succ_l. - -Theorem Zlt_succ_l : forall n m : Z, S n < m -> n < m. -Proof NZlt_succ_l. - -Theorem Zsucc_lt_mono : forall n m : Z, n < m <-> S n < S m. -Proof NZsucc_lt_mono. - -Theorem Zsucc_le_mono : forall n m : Z, n <= m <-> S n <= S m. -Proof NZsucc_le_mono. - -Theorem Zlt_asymm : forall n m, n < m -> ~ m < n. -Proof NZlt_asymm. - -Notation Zlt_ngt := Zlt_asymm (only parsing). - -Theorem Zlt_trans : forall n m p : Z, n < m -> m < p -> n < p. -Proof NZlt_trans. - -Theorem Zle_trans : forall n m p : Z, n <= m -> m <= p -> n <= p. -Proof NZle_trans. - -Theorem Zle_lt_trans : forall n m p : Z, n <= m -> m < p -> n < p. -Proof NZle_lt_trans. - -Theorem Zlt_le_trans : forall n m p : Z, n < m -> m <= p -> n < p. -Proof NZlt_le_trans. - -Theorem Zle_antisymm : forall n m : Z, n <= m -> m <= n -> n == m. -Proof NZle_antisymm. - -Theorem Zlt_1_l : forall n m : Z, 0 < n -> n < m -> 1 < m. -Proof NZlt_1_l. - -(** Trichotomy, decidability, and double negation elimination *) - -Theorem Zlt_trichotomy : forall n m : Z, n < m \/ n == m \/ m < n. -Proof NZlt_trichotomy. - -Notation Zlt_eq_gt_cases := Zlt_trichotomy (only parsing). - -Theorem Zlt_gt_cases : forall n m : Z, n ~= m <-> n < m \/ n > m. -Proof NZlt_gt_cases. - -Theorem Zle_gt_cases : forall n m : Z, n <= m \/ n > m. -Proof NZle_gt_cases. - -Theorem Zlt_ge_cases : forall n m : Z, n < m \/ n >= m. -Proof NZlt_ge_cases. - -Theorem Zle_ge_cases : forall n m : Z, n <= m \/ n >= m. -Proof NZle_ge_cases. - -(** Instances of the previous theorems for m == 0 *) - -Theorem Zneg_pos_cases : forall n : Z, n ~= 0 <-> n < 0 \/ n > 0. +Theorem neg_pos_cases : forall n, n ~= 0 <-> n < 0 \/ n > 0. Proof. -intro; apply Zlt_gt_cases. +intro; apply lt_gt_cases. Qed. -Theorem Znonpos_pos_cases : forall n : Z, n <= 0 \/ n > 0. +Theorem nonpos_pos_cases : forall n, n <= 0 \/ n > 0. Proof. -intro; apply Zle_gt_cases. +intro; apply le_gt_cases. Qed. -Theorem Zneg_nonneg_cases : forall n : Z, n < 0 \/ n >= 0. +Theorem neg_nonneg_cases : forall n, n < 0 \/ n >= 0. Proof. -intro; apply Zlt_ge_cases. +intro; apply lt_ge_cases. Qed. -Theorem Znonpos_nonneg_cases : forall n : Z, n <= 0 \/ n >= 0. +Theorem nonpos_nonneg_cases : forall n, n <= 0 \/ n >= 0. Proof. -intro; apply Zle_ge_cases. +intro; apply le_ge_cases. Qed. -Theorem Zle_ngt : forall n m : Z, n <= m <-> ~ n > m. -Proof NZle_ngt. - -Theorem Znlt_ge : forall n m : Z, ~ n < m <-> n >= m. -Proof NZnlt_ge. - -Theorem Zlt_dec : forall n m : Z, decidable (n < m). -Proof NZlt_dec. - -Theorem Zlt_dne : forall n m, ~ ~ n < m <-> n < m. -Proof NZlt_dne. - -Theorem Znle_gt : forall n m : Z, ~ n <= m <-> n > m. -Proof NZnle_gt. - -Theorem Zlt_nge : forall n m : Z, n < m <-> ~ n >= m. -Proof NZlt_nge. - -Theorem Zle_dec : forall n m : Z, decidable (n <= m). -Proof NZle_dec. - -Theorem Zle_dne : forall n m : Z, ~ ~ n <= m <-> n <= m. -Proof NZle_dne. - -Theorem Znlt_succ_r : forall n m : Z, ~ m < S n <-> n < m. -Proof NZnlt_succ_r. - -Theorem Zlt_exists_pred : - forall z n : Z, z < n -> exists k : Z, n == S k /\ z <= k. -Proof NZlt_exists_pred. - -Theorem Zlt_succ_iter_r : - forall (n : nat) (m : Z), m < NZsucc_iter (Datatypes.S n) m. -Proof NZlt_succ_iter_r. - -Theorem Zneq_succ_iter_l : - forall (n : nat) (m : Z), NZsucc_iter (Datatypes.S n) m ~= m. -Proof NZneq_succ_iter_l. - -(** Stronger variant of induction with assumptions n >= 0 (n < 0) -in the induction step *) - -Theorem Zright_induction : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, A z -> - (forall n : Z, z <= n -> A n -> A (S n)) -> - forall n : Z, z <= n -> A n. -Proof NZright_induction. - -Theorem Zleft_induction : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, A z -> - (forall n : Z, n < z -> A (S n) -> A n) -> - forall n : Z, n <= z -> A n. -Proof NZleft_induction. - -Theorem Zright_induction' : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, - (forall n : Z, n <= z -> A n) -> - (forall n : Z, z <= n -> A n -> A (S n)) -> - forall n : Z, A n. -Proof NZright_induction'. - -Theorem Zleft_induction' : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, - (forall n : Z, z <= n -> A n) -> - (forall n : Z, n < z -> A (S n) -> A n) -> - forall n : Z, A n. -Proof NZleft_induction'. - -Theorem Zstrong_right_induction : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, - (forall n : Z, z <= n -> (forall m : Z, z <= m -> m < n -> A m) -> A n) -> - forall n : Z, z <= n -> A n. -Proof NZstrong_right_induction. - -Theorem Zstrong_left_induction : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, - (forall n : Z, n <= z -> (forall m : Z, m <= z -> S n <= m -> A m) -> A n) -> - forall n : Z, n <= z -> A n. -Proof NZstrong_left_induction. - -Theorem Zstrong_right_induction' : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, - (forall n : Z, n <= z -> A n) -> - (forall n : Z, z <= n -> (forall m : Z, z <= m -> m < n -> A m) -> A n) -> - forall n : Z, A n. -Proof NZstrong_right_induction'. - -Theorem Zstrong_left_induction' : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, - (forall n : Z, z <= n -> A n) -> - (forall n : Z, n <= z -> (forall m : Z, m <= z -> S n <= m -> A m) -> A n) -> - forall n : Z, A n. -Proof NZstrong_left_induction'. - -Theorem Zorder_induction : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, A z -> - (forall n : Z, z <= n -> A n -> A (S n)) -> - (forall n : Z, n < z -> A (S n) -> A n) -> - forall n : Z, A n. -Proof NZorder_induction. - -Theorem Zorder_induction' : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall z : Z, A z -> - (forall n : Z, z <= n -> A n -> A (S n)) -> - (forall n : Z, n <= z -> A n -> A (P n)) -> - forall n : Z, A n. -Proof NZorder_induction'. - -Theorem Zorder_induction_0 : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - A 0 -> - (forall n : Z, 0 <= n -> A n -> A (S n)) -> - (forall n : Z, n < 0 -> A (S n) -> A n) -> - forall n : Z, A n. -Proof NZorder_induction_0. - -Theorem Zorder_induction'_0 : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - A 0 -> - (forall n : Z, 0 <= n -> A n -> A (S n)) -> - (forall n : Z, n <= 0 -> A n -> A (P n)) -> - forall n : Z, A n. -Proof NZorder_induction'_0. - -Ltac Zinduct n := induction_maker n ltac:(apply Zorder_induction_0). - -(** Elimintation principle for < *) - -Theorem Zlt_ind : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall n : Z, A (S n) -> - (forall m : Z, n < m -> A m -> A (S m)) -> forall m : Z, n < m -> A m. -Proof NZlt_ind. - -(** Elimintation principle for <= *) - -Theorem Zle_ind : - forall A : Z -> Prop, Proper (Zeq==>iff) A -> - forall n : Z, A n -> - (forall m : Z, n <= m -> A m -> A (S m)) -> forall m : Z, n <= m -> A m. -Proof NZle_ind. - -(** Well-founded relations *) - -Theorem Zlt_wf : forall z : Z, well_founded (fun n m : Z => z <= n /\ n < m). -Proof NZlt_wf. - -Theorem Zgt_wf : forall z : Z, well_founded (fun n m : Z => m < n /\ n <= z). -Proof NZgt_wf. +Ltac zinduct n := induction_maker n ltac:(apply order_induction_0). -(* Theorems that are either not valid on N or have different proofs on N and Z *) +(** Theorems that are either not valid on N or have different proofs + on N and Z *) -Theorem Zlt_pred_l : forall n : Z, P n < n. +Theorem lt_pred_l : forall n, P n < n. Proof. -intro n; rewrite <- (Zsucc_pred n) at 2; apply Zlt_succ_diag_r. +intro n; rewrite <- (succ_pred n) at 2; apply lt_succ_diag_r. Qed. -Theorem Zle_pred_l : forall n : Z, P n <= n. +Theorem le_pred_l : forall n, P n <= n. Proof. -intro; apply Zlt_le_incl; apply Zlt_pred_l. +intro; apply lt_le_incl; apply lt_pred_l. Qed. -Theorem Zlt_le_pred : forall n m : Z, n < m <-> n <= P m. +Theorem lt_le_pred : forall n m, n < m <-> n <= P m. Proof. -intros n m; rewrite <- (Zsucc_pred m); rewrite Zpred_succ. apply Zlt_succ_r. +intros n m; rewrite <- (succ_pred m); rewrite pred_succ. apply lt_succ_r. Qed. -Theorem Znle_pred_r : forall n : Z, ~ n <= P n. +Theorem nle_pred_r : forall n, ~ n <= P n. Proof. -intro; rewrite <- Zlt_le_pred; apply Zlt_irrefl. +intro; rewrite <- lt_le_pred; apply lt_irrefl. Qed. -Theorem Zlt_pred_le : forall n m : Z, P n < m <-> n <= m. +Theorem lt_pred_le : forall n m, P n < m <-> n <= m. Proof. -intros n m; rewrite <- (Zsucc_pred n) at 2. -symmetry; apply Zle_succ_l. +intros n m; rewrite <- (succ_pred n) at 2. +symmetry; apply le_succ_l. Qed. -Theorem Zlt_lt_pred : forall n m : Z, n < m -> P n < m. +Theorem lt_lt_pred : forall n m, n < m -> P n < m. Proof. -intros; apply <- Zlt_pred_le; now apply Zlt_le_incl. +intros; apply <- lt_pred_le; now apply lt_le_incl. Qed. -Theorem Zle_le_pred : forall n m : Z, n <= m -> P n <= m. +Theorem le_le_pred : forall n m, n <= m -> P n <= m. Proof. -intros; apply Zlt_le_incl; now apply <- Zlt_pred_le. +intros; apply lt_le_incl; now apply <- lt_pred_le. Qed. -Theorem Zlt_pred_lt : forall n m : Z, n < P m -> n < m. +Theorem lt_pred_lt : forall n m, n < P m -> n < m. Proof. -intros n m H; apply Zlt_trans with (P m); [assumption | apply Zlt_pred_l]. +intros n m H; apply lt_trans with (P m); [assumption | apply lt_pred_l]. Qed. -Theorem Zle_pred_lt : forall n m : Z, n <= P m -> n <= m. +Theorem le_pred_lt : forall n m, n <= P m -> n <= m. Proof. -intros; apply Zlt_le_incl; now apply <- Zlt_le_pred. +intros; apply lt_le_incl; now apply <- lt_le_pred. Qed. -Theorem Zpred_lt_mono : forall n m : Z, n < m <-> P n < P m. +Theorem pred_lt_mono : forall n m, n < m <-> P n < P m. Proof. -intros; rewrite Zlt_le_pred; symmetry; apply Zlt_pred_le. +intros; rewrite lt_le_pred; symmetry; apply lt_pred_le. Qed. -Theorem Zpred_le_mono : forall n m : Z, n <= m <-> P n <= P m. +Theorem pred_le_mono : forall n m, n <= m <-> P n <= P m. Proof. -intros; rewrite <- Zlt_pred_le; now rewrite Zlt_le_pred. +intros; rewrite <- lt_pred_le; now rewrite lt_le_pred. Qed. -Theorem Zlt_succ_lt_pred : forall n m : Z, S n < m <-> n < P m. +Theorem lt_succ_lt_pred : forall n m, S n < m <-> n < P m. Proof. -intros n m; now rewrite (Zpred_lt_mono (S n) m), Zpred_succ. +intros n m; now rewrite (pred_lt_mono (S n) m), pred_succ. Qed. -Theorem Zle_succ_le_pred : forall n m : Z, S n <= m <-> n <= P m. +Theorem le_succ_le_pred : forall n m, S n <= m <-> n <= P m. Proof. -intros n m; now rewrite (Zpred_le_mono (S n) m), Zpred_succ. +intros n m; now rewrite (pred_le_mono (S n) m), pred_succ. Qed. -Theorem Zlt_pred_lt_succ : forall n m : Z, P n < m <-> n < S m. +Theorem lt_pred_lt_succ : forall n m, P n < m <-> n < S m. Proof. -intros; rewrite Zlt_pred_le; symmetry; apply Zlt_succ_r. +intros; rewrite lt_pred_le; symmetry; apply lt_succ_r. Qed. -Theorem Zle_pred_lt_succ : forall n m : Z, P n <= m <-> n <= S m. +Theorem le_pred_lt_succ : forall n m, P n <= m <-> n <= S m. Proof. -intros n m; now rewrite (Zpred_le_mono n (S m)), Zpred_succ. +intros n m; now rewrite (pred_le_mono n (S m)), pred_succ. Qed. -Theorem Zneq_pred_l : forall n : Z, P n ~= n. +Theorem neq_pred_l : forall n, P n ~= n. Proof. -intro; apply Zlt_neq; apply Zlt_pred_l. +intro; apply lt_neq; apply lt_pred_l. Qed. -Theorem Zlt_n1_r : forall n m : Z, n < m -> m < 0 -> n < -1. +Theorem lt_n1_r : forall n m, n < m -> m < 0 -> n < -1. Proof. -intros n m H1 H2. apply -> Zlt_le_pred in H2. -setoid_replace (P 0) with (-1) in H2. now apply NZlt_le_trans with m. -apply <- Zeq_opp_r. now rewrite Zopp_pred, Zopp_0. +intros n m H1 H2. apply -> lt_le_pred in H2. +setoid_replace (P 0) with (-1) in H2. now apply lt_le_trans with m. +apply <- eq_opp_r. now rewrite opp_pred, opp_0. Qed. End ZOrderPropFunct. diff --git a/theories/Numbers/Integer/Abstract/ZMul.v b/theories/Numbers/Integer/Abstract/ZMul.v index 785c0f41b..4be2ac887 100644 --- a/theories/Numbers/Integer/Abstract/ZMul.v +++ b/theories/Numbers/Integer/Abstract/ZMul.v @@ -12,102 +12,60 @@ Require Export ZAdd. -Module ZMulPropFunct (Import ZAxiomsMod : ZAxiomsSig). -Module Export ZAddPropMod := ZAddPropFunct ZAxiomsMod. -Open Local Scope IntScope. - -Theorem Zmul_wd : - forall n1 n2 : Z, n1 == n2 -> forall m1 m2 : Z, m1 == m2 -> n1 * m1 == n2 * m2. -Proof NZmul_wd. - -Theorem Zmul_0_l : forall n : Z, 0 * n == 0. -Proof NZmul_0_l. - -Theorem Zmul_succ_l : forall n m : Z, (S n) * m == n * m + m. -Proof NZmul_succ_l. - -(* Theorems that are valid for both natural numbers and integers *) - -Theorem Zmul_0_r : forall n : Z, n * 0 == 0. -Proof NZmul_0_r. - -Theorem Zmul_succ_r : forall n m : Z, n * (S m) == n * m + n. -Proof NZmul_succ_r. - -Theorem Zmul_comm : forall n m : Z, n * m == m * n. -Proof NZmul_comm. - -Theorem Zmul_add_distr_r : forall n m p : Z, (n + m) * p == n * p + m * p. -Proof NZmul_add_distr_r. - -Theorem Zmul_add_distr_l : forall n m p : Z, n * (m + p) == n * m + n * p. -Proof NZmul_add_distr_l. - -(* A note on naming: right (correspondingly, left) distributivity happens -when the sum is multiplied by a number on the right (left), not when the -sum itself is the right (left) factor in the product (see planetmath.org -and mathworld.wolfram.com). In the old library BinInt, distributivity over -subtraction was named correctly, but distributivity over addition was named -incorrectly. The names in Isabelle/HOL library are also incorrect. *) - -Theorem Zmul_assoc : forall n m p : Z, n * (m * p) == (n * m) * p. -Proof NZmul_assoc. - -Theorem Zmul_1_l : forall n : Z, 1 * n == n. -Proof NZmul_1_l. - -Theorem Zmul_1_r : forall n : Z, n * 1 == n. -Proof NZmul_1_r. - -(* The following two theorems are true in an ordered ring, -but since they don't mention order, we'll put them here *) - -Theorem Zeq_mul_0 : forall n m : Z, n * m == 0 <-> n == 0 \/ m == 0. -Proof NZeq_mul_0. - -Theorem Zneq_mul_0 : forall n m : Z, n ~= 0 /\ m ~= 0 <-> n * m ~= 0. -Proof NZneq_mul_0. - -(* Theorems that are either not valid on N or have different proofs on N and Z *) - -Theorem Zmul_pred_r : forall n m : Z, n * (P m) == n * m - n. +Module ZMulPropFunct (Import Z : ZAxiomsSig). +Include ZAddPropFunct Z. +Local Open Scope NumScope. + +(** A note on naming: right (correspondingly, left) distributivity + happens when the sum is multiplied by a number on the right + (left), not when the sum itself is the right (left) factor in the + product (see planetmath.org and mathworld.wolfram.com). In the old + library BinInt, distributivity over subtraction was named + correctly, but distributivity over addition was named + incorrectly. The names in Isabelle/HOL library are also + incorrect. *) + +(** Theorems that are either not valid on N or have different proofs + on N and Z *) + +Theorem mul_pred_r : forall n m, n * (P m) == n * m - n. Proof. intros n m. -rewrite <- (Zsucc_pred m) at 2. -now rewrite Zmul_succ_r, <- Zadd_sub_assoc, Zsub_diag, Zadd_0_r. +rewrite <- (succ_pred m) at 2. +now rewrite mul_succ_r, <- add_sub_assoc, sub_diag, add_0_r. Qed. -Theorem Zmul_pred_l : forall n m : Z, (P n) * m == n * m - m. +Theorem mul_pred_l : forall n m, (P n) * m == n * m - m. Proof. -intros n m; rewrite (Zmul_comm (P n) m), (Zmul_comm n m). apply Zmul_pred_r. +intros n m; rewrite (mul_comm (P n) m), (mul_comm n m). apply mul_pred_r. Qed. -Theorem Zmul_opp_l : forall n m : Z, (- n) * m == - (n * m). +Theorem mul_opp_l : forall n m, (- n) * m == - (n * m). Proof. -intros n m. apply -> Zadd_move_0_r. -now rewrite <- Zmul_add_distr_r, Zadd_opp_diag_l, Zmul_0_l. +intros n m. apply -> add_move_0_r. +now rewrite <- mul_add_distr_r, add_opp_diag_l, mul_0_l. Qed. -Theorem Zmul_opp_r : forall n m : Z, n * (- m) == - (n * m). +Theorem mul_opp_r : forall n m, n * (- m) == - (n * m). Proof. -intros n m; rewrite (Zmul_comm n (- m)), (Zmul_comm n m); apply Zmul_opp_l. +intros n m; rewrite (mul_comm n (- m)), (mul_comm n m); apply mul_opp_l. Qed. -Theorem Zmul_opp_opp : forall n m : Z, (- n) * (- m) == n * m. +Theorem mul_opp_opp : forall n m, (- n) * (- m) == n * m. Proof. -intros n m; now rewrite Zmul_opp_l, Zmul_opp_r, Zopp_involutive. +intros n m; now rewrite mul_opp_l, mul_opp_r, opp_involutive. Qed. -Theorem Zmul_sub_distr_l : forall n m p : Z, n * (m - p) == n * m - n * p. +Theorem mul_sub_distr_l : forall n m p, n * (m - p) == n * m - n * p. Proof. -intros n m p. do 2 rewrite <- Zadd_opp_r. rewrite Zmul_add_distr_l. -now rewrite Zmul_opp_r. +intros n m p. do 2 rewrite <- add_opp_r. rewrite mul_add_distr_l. +now rewrite mul_opp_r. Qed. -Theorem Zmul_sub_distr_r : forall n m p : Z, (n - m) * p == n * p - m * p. +Theorem mul_sub_distr_r : forall n m p, (n - m) * p == n * p - m * p. Proof. -intros n m p; rewrite (Zmul_comm (n - m) p), (Zmul_comm n p), (Zmul_comm m p); -now apply Zmul_sub_distr_l. +intros n m p; rewrite (mul_comm (n - m) p), (mul_comm n p), (mul_comm m p); +now apply mul_sub_distr_l. Qed. End ZMulPropFunct. diff --git a/theories/Numbers/Integer/Abstract/ZMulOrder.v b/theories/Numbers/Integer/Abstract/ZMulOrder.v index 74c893594..4f11dcc5c 100644 --- a/theories/Numbers/Integer/Abstract/ZMulOrder.v +++ b/theories/Numbers/Integer/Abstract/ZMulOrder.v @@ -12,331 +12,226 @@ Require Export ZAddOrder. -Module ZMulOrderPropFunct (Import ZAxiomsMod : ZAxiomsSig). -Module Export ZAddOrderPropMod := ZAddOrderPropFunct ZAxiomsMod. -Open Local Scope IntScope. +Module ZMulOrderPropFunct (Import Z : ZAxiomsSig). +Include ZAddOrderPropFunct Z. +Local Open Scope NumScope. -Theorem Zmul_lt_pred : - forall p q n m : Z, S p == q -> (p * n < p * m <-> q * n + m < q * m + n). -Proof NZmul_lt_pred. - -Theorem Zmul_lt_mono_pos_l : forall p n m : Z, 0 < p -> (n < m <-> p * n < p * m). -Proof NZmul_lt_mono_pos_l. - -Theorem Zmul_lt_mono_pos_r : forall p n m : Z, 0 < p -> (n < m <-> n * p < m * p). -Proof NZmul_lt_mono_pos_r. - -Theorem Zmul_lt_mono_neg_l : forall p n m : Z, p < 0 -> (n < m <-> p * m < p * n). -Proof NZmul_lt_mono_neg_l. - -Theorem Zmul_lt_mono_neg_r : forall p n m : Z, p < 0 -> (n < m <-> m * p < n * p). -Proof NZmul_lt_mono_neg_r. - -Theorem Zmul_le_mono_nonneg_l : forall n m p : Z, 0 <= p -> n <= m -> p * n <= p * m. -Proof NZmul_le_mono_nonneg_l. - -Theorem Zmul_le_mono_nonpos_l : forall n m p : Z, p <= 0 -> n <= m -> p * m <= p * n. -Proof NZmul_le_mono_nonpos_l. - -Theorem Zmul_le_mono_nonneg_r : forall n m p : Z, 0 <= p -> n <= m -> n * p <= m * p. -Proof NZmul_le_mono_nonneg_r. - -Theorem Zmul_le_mono_nonpos_r : forall n m p : Z, p <= 0 -> n <= m -> m * p <= n * p. -Proof NZmul_le_mono_nonpos_r. - -Theorem Zmul_cancel_l : forall n m p : Z, p ~= 0 -> (p * n == p * m <-> n == m). -Proof NZmul_cancel_l. - -Theorem Zmul_cancel_r : forall n m p : Z, p ~= 0 -> (n * p == m * p <-> n == m). -Proof NZmul_cancel_r. - -Theorem Zmul_id_l : forall n m : Z, m ~= 0 -> (n * m == m <-> n == 1). -Proof NZmul_id_l. - -Theorem Zmul_id_r : forall n m : Z, n ~= 0 -> (n * m == n <-> m == 1). -Proof NZmul_id_r. - -Theorem Zmul_le_mono_pos_l : forall n m p : Z, 0 < p -> (n <= m <-> p * n <= p * m). -Proof NZmul_le_mono_pos_l. - -Theorem Zmul_le_mono_pos_r : forall n m p : Z, 0 < p -> (n <= m <-> n * p <= m * p). -Proof NZmul_le_mono_pos_r. - -Theorem Zmul_le_mono_neg_l : forall n m p : Z, p < 0 -> (n <= m <-> p * m <= p * n). -Proof NZmul_le_mono_neg_l. - -Theorem Zmul_le_mono_neg_r : forall n m p : Z, p < 0 -> (n <= m <-> m * p <= n * p). -Proof NZmul_le_mono_neg_r. - -Theorem Zmul_lt_mono_nonneg : - forall n m p q : Z, 0 <= n -> n < m -> 0 <= p -> p < q -> n * p < m * q. -Proof NZmul_lt_mono_nonneg. - -Theorem Zmul_lt_mono_nonpos : - forall n m p q : Z, m <= 0 -> n < m -> q <= 0 -> p < q -> m * q < n * p. +Theorem mul_lt_mono_nonpos : + forall n m p q, m <= 0 -> n < m -> q <= 0 -> p < q -> m * q < n * p. Proof. intros n m p q H1 H2 H3 H4. -apply Zle_lt_trans with (m * p). -apply Zmul_le_mono_nonpos_l; [assumption | now apply Zlt_le_incl]. -apply -> Zmul_lt_mono_neg_r; [assumption | now apply Zlt_le_trans with q]. +apply le_lt_trans with (m * p). +apply mul_le_mono_nonpos_l; [assumption | now apply lt_le_incl]. +apply -> mul_lt_mono_neg_r; [assumption | now apply lt_le_trans with q]. Qed. -Theorem Zmul_le_mono_nonneg : - forall n m p q : Z, 0 <= n -> n <= m -> 0 <= p -> p <= q -> n * p <= m * q. -Proof NZmul_le_mono_nonneg. - -Theorem Zmul_le_mono_nonpos : - forall n m p q : Z, m <= 0 -> n <= m -> q <= 0 -> p <= q -> m * q <= n * p. +Theorem mul_le_mono_nonpos : + forall n m p q, m <= 0 -> n <= m -> q <= 0 -> p <= q -> m * q <= n * p. Proof. intros n m p q H1 H2 H3 H4. -apply Zle_trans with (m * p). -now apply Zmul_le_mono_nonpos_l. -apply Zmul_le_mono_nonpos_r; [now apply Zle_trans with q | assumption]. +apply le_trans with (m * p). +now apply mul_le_mono_nonpos_l. +apply mul_le_mono_nonpos_r; [now apply le_trans with q | assumption]. Qed. -Theorem Zmul_pos_pos : forall n m : Z, 0 < n -> 0 < m -> 0 < n * m. -Proof NZmul_pos_pos. - -Theorem Zmul_neg_neg : forall n m : Z, n < 0 -> m < 0 -> 0 < n * m. -Proof NZmul_neg_neg. - -Theorem Zmul_pos_neg : forall n m : Z, 0 < n -> m < 0 -> n * m < 0. -Proof NZmul_pos_neg. - -Theorem Zmul_neg_pos : forall n m : Z, n < 0 -> 0 < m -> n * m < 0. -Proof NZmul_neg_pos. - -Theorem Zmul_nonneg_nonneg : forall n m : Z, 0 <= n -> 0 <= m -> 0 <= n * m. +Theorem mul_nonneg_nonneg : forall n m, 0 <= n -> 0 <= m -> 0 <= n * m. Proof. intros n m H1 H2. -rewrite <- (Zmul_0_l m). now apply Zmul_le_mono_nonneg_r. +rewrite <- (mul_0_l m). now apply mul_le_mono_nonneg_r. Qed. -Theorem Zmul_nonpos_nonpos : forall n m : Z, n <= 0 -> m <= 0 -> 0 <= n * m. +Theorem mul_nonpos_nonpos : forall n m, n <= 0 -> m <= 0 -> 0 <= n * m. Proof. intros n m H1 H2. -rewrite <- (Zmul_0_l m). now apply Zmul_le_mono_nonpos_r. +rewrite <- (mul_0_l m). now apply mul_le_mono_nonpos_r. Qed. -Theorem Zmul_nonneg_nonpos : forall n m : Z, 0 <= n -> m <= 0 -> n * m <= 0. +Theorem mul_nonneg_nonpos : forall n m, 0 <= n -> m <= 0 -> n * m <= 0. Proof. intros n m H1 H2. -rewrite <- (Zmul_0_l m). now apply Zmul_le_mono_nonpos_r. +rewrite <- (mul_0_l m). now apply mul_le_mono_nonpos_r. Qed. -Theorem Zmul_nonpos_nonneg : forall n m : Z, n <= 0 -> 0 <= m -> n * m <= 0. +Theorem mul_nonpos_nonneg : forall n m, n <= 0 -> 0 <= m -> n * m <= 0. Proof. -intros; rewrite Zmul_comm; now apply Zmul_nonneg_nonpos. +intros; rewrite mul_comm; now apply mul_nonneg_nonpos. Qed. -Theorem Zlt_1_mul_pos : forall n m : Z, 1 < n -> 0 < m -> 1 < n * m. -Proof NZlt_1_mul_pos. - -Theorem Zeq_mul_0 : forall n m : Z, n * m == 0 <-> n == 0 \/ m == 0. -Proof NZeq_mul_0. - -Theorem Zneq_mul_0 : forall n m : Z, n ~= 0 /\ m ~= 0 <-> n * m ~= 0. -Proof NZneq_mul_0. - -Theorem Zeq_square_0 : forall n : Z, n * n == 0 <-> n == 0. -Proof NZeq_square_0. - -Theorem Zeq_mul_0_l : forall n m : Z, n * m == 0 -> m ~= 0 -> n == 0. -Proof NZeq_mul_0_l. +Notation mul_pos := lt_0_mul (only parsing). -Theorem Zeq_mul_0_r : forall n m : Z, n * m == 0 -> n ~= 0 -> m == 0. -Proof NZeq_mul_0_r. - -Theorem Zlt_0_mul : forall n m : Z, 0 < n * m <-> 0 < n /\ 0 < m \/ m < 0 /\ n < 0. -Proof NZlt_0_mul. - -Notation Zmul_pos := Zlt_0_mul (only parsing). - -Theorem Zlt_mul_0 : - forall n m : Z, n * m < 0 <-> n < 0 /\ m > 0 \/ n > 0 /\ m < 0. +Theorem lt_mul_0 : + forall n m, n * m < 0 <-> n < 0 /\ m > 0 \/ n > 0 /\ m < 0. Proof. intros n m; split; [intro H | intros [[H1 H2] | [H1 H2]]]. -destruct (Zlt_trichotomy n 0) as [H1 | [H1 | H1]]; -[| rewrite H1 in H; rewrite Zmul_0_l in H; false_hyp H Zlt_irrefl |]; -(destruct (Zlt_trichotomy m 0) as [H2 | [H2 | H2]]; -[| rewrite H2 in H; rewrite Zmul_0_r in H; false_hyp H Zlt_irrefl |]); +destruct (lt_trichotomy n 0) as [H1 | [H1 | H1]]; +[| rewrite H1 in H; rewrite mul_0_l in H; false_hyp H lt_irrefl |]; +(destruct (lt_trichotomy m 0) as [H2 | [H2 | H2]]; +[| rewrite H2 in H; rewrite mul_0_r in H; false_hyp H lt_irrefl |]); try (left; now split); try (right; now split). -assert (H3 : n * m > 0) by now apply Zmul_neg_neg. -exfalso; now apply (Zlt_asymm (n * m) 0). -assert (H3 : n * m > 0) by now apply Zmul_pos_pos. -exfalso; now apply (Zlt_asymm (n * m) 0). -now apply Zmul_neg_pos. now apply Zmul_pos_neg. +assert (H3 : n * m > 0) by now apply mul_neg_neg. +exfalso; now apply (lt_asymm (n * m) 0). +assert (H3 : n * m > 0) by now apply mul_pos_pos. +exfalso; now apply (lt_asymm (n * m) 0). +now apply mul_neg_pos. now apply mul_pos_neg. Qed. -Notation Zmul_neg := Zlt_mul_0 (only parsing). +Notation mul_neg := lt_mul_0 (only parsing). -Theorem Zle_0_mul : - forall n m : Z, 0 <= n * m -> 0 <= n /\ 0 <= m \/ n <= 0 /\ m <= 0. +Theorem le_0_mul : + forall n m, 0 <= n * m -> 0 <= n /\ 0 <= m \/ n <= 0 /\ m <= 0. Proof. -assert (R : forall n : Z, 0 == n <-> n == 0) by (intros; split; apply Zeq_sym). -intros n m. repeat rewrite Zlt_eq_cases. repeat rewrite R. -rewrite Zlt_0_mul, Zeq_mul_0. -pose proof (Zlt_trichotomy n 0); pose proof (Zlt_trichotomy m 0). tauto. +assert (R : forall n, 0 == n <-> n == 0) by (intros; split; apply eq_sym). +intros n m. repeat rewrite lt_eq_cases. repeat rewrite R. +rewrite lt_0_mul, eq_mul_0. +pose proof (lt_trichotomy n 0); pose proof (lt_trichotomy m 0). tauto. Qed. -Notation Zmul_nonneg := Zle_0_mul (only parsing). +Notation mul_nonneg := le_0_mul (only parsing). -Theorem Zle_mul_0 : - forall n m : Z, n * m <= 0 -> 0 <= n /\ m <= 0 \/ n <= 0 /\ 0 <= m. +Theorem le_mul_0 : + forall n m, n * m <= 0 -> 0 <= n /\ m <= 0 \/ n <= 0 /\ 0 <= m. Proof. -assert (R : forall n : Z, 0 == n <-> n == 0) by (intros; split; apply Zeq_sym). -intros n m. repeat rewrite Zlt_eq_cases. repeat rewrite R. -rewrite Zlt_mul_0, Zeq_mul_0. -pose proof (Zlt_trichotomy n 0); pose proof (Zlt_trichotomy m 0). tauto. +assert (R : forall n, 0 == n <-> n == 0) by (intros; split; apply eq_sym). +intros n m. repeat rewrite lt_eq_cases. repeat rewrite R. +rewrite lt_mul_0, eq_mul_0. +pose proof (lt_trichotomy n 0); pose proof (lt_trichotomy m 0). tauto. Qed. -Notation Zmul_nonpos := Zle_mul_0 (only parsing). +Notation mul_nonpos := le_mul_0 (only parsing). -Theorem Zle_0_square : forall n : Z, 0 <= n * n. +Theorem le_0_square : forall n, 0 <= n * n. Proof. -intro n; destruct (Zneg_nonneg_cases n). -apply Zlt_le_incl; now apply Zmul_neg_neg. -now apply Zmul_nonneg_nonneg. +intro n; destruct (neg_nonneg_cases n). +apply lt_le_incl; now apply mul_neg_neg. +now apply mul_nonneg_nonneg. Qed. -Notation Zsquare_nonneg := Zle_0_square (only parsing). +Notation square_nonneg := le_0_square (only parsing). -Theorem Znlt_square_0 : forall n : Z, ~ n * n < 0. +Theorem nlt_square_0 : forall n, ~ n * n < 0. Proof. -intros n H. apply -> Zlt_nge in H. apply H. apply Zsquare_nonneg. +intros n H. apply -> lt_nge in H. apply H. apply square_nonneg. Qed. -Theorem Zsquare_lt_mono_nonneg : forall n m : Z, 0 <= n -> n < m -> n * n < m * m. -Proof NZsquare_lt_mono_nonneg. - -Theorem Zsquare_lt_mono_nonpos : forall n m : Z, n <= 0 -> m < n -> n * n < m * m. +Theorem square_lt_mono_nonpos : forall n m, n <= 0 -> m < n -> n * n < m * m. Proof. -intros n m H1 H2. now apply Zmul_lt_mono_nonpos. +intros n m H1 H2. now apply mul_lt_mono_nonpos. Qed. -Theorem Zsquare_le_mono_nonneg : forall n m : Z, 0 <= n -> n <= m -> n * n <= m * m. -Proof NZsquare_le_mono_nonneg. - -Theorem Zsquare_le_mono_nonpos : forall n m : Z, n <= 0 -> m <= n -> n * n <= m * m. +Theorem square_le_mono_nonpos : forall n m, n <= 0 -> m <= n -> n * n <= m * m. Proof. -intros n m H1 H2. now apply Zmul_le_mono_nonpos. +intros n m H1 H2. now apply mul_le_mono_nonpos. Qed. -Theorem Zsquare_lt_simpl_nonneg : forall n m : Z, 0 <= m -> n * n < m * m -> n < m. -Proof NZsquare_lt_simpl_nonneg. - -Theorem Zsquare_le_simpl_nonneg : forall n m : Z, 0 <= m -> n * n <= m * m -> n <= m. -Proof NZsquare_le_simpl_nonneg. - -Theorem Zsquare_lt_simpl_nonpos : forall n m : Z, m <= 0 -> n * n < m * m -> m < n. +Theorem square_lt_simpl_nonpos : forall n m, m <= 0 -> n * n < m * m -> m < n. Proof. -intros n m H1 H2. destruct (Zle_gt_cases n 0). -destruct (NZlt_ge_cases m n). -assumption. assert (F : m * m <= n * n) by now apply Zsquare_le_mono_nonpos. -apply -> NZle_ngt in F. false_hyp H2 F. -now apply Zle_lt_trans with 0. +intros n m H1 H2. destruct (le_gt_cases n 0). +destruct (lt_ge_cases m n). +assumption. assert (F : m * m <= n * n) by now apply square_le_mono_nonpos. +apply -> le_ngt in F. false_hyp H2 F. +now apply le_lt_trans with 0. Qed. -Theorem Zsquare_le_simpl_nonpos : forall n m : NZ, m <= 0 -> n * n <= m * m -> m <= n. +Theorem square_le_simpl_nonpos : forall n m, m <= 0 -> n * n <= m * m -> m <= n. Proof. -intros n m H1 H2. destruct (NZle_gt_cases n 0). -destruct (NZle_gt_cases m n). -assumption. assert (F : m * m < n * n) by now apply Zsquare_lt_mono_nonpos. -apply -> NZlt_nge in F. false_hyp H2 F. -apply Zlt_le_incl; now apply NZle_lt_trans with 0. +intros n m H1 H2. destruct (le_gt_cases n 0). +destruct (le_gt_cases m n). +assumption. assert (F : m * m < n * n) by now apply square_lt_mono_nonpos. +apply -> lt_nge in F. false_hyp H2 F. +apply lt_le_incl; now apply le_lt_trans with 0. Qed. -Theorem Zmul_2_mono_l : forall n m : Z, n < m -> 1 + (1 + 1) * n < (1 + 1) * m. -Proof NZmul_2_mono_l. - -Theorem Zlt_1_mul_neg : forall n m : Z, n < -1 -> m < 0 -> 1 < n * m. +Theorem lt_1_mul_neg : forall n m, n < -1 -> m < 0 -> 1 < n * m. Proof. -intros n m H1 H2. apply -> (NZmul_lt_mono_neg_r m) in H1. -apply <- Zopp_pos_neg in H2. rewrite Zmul_opp_l, Zmul_1_l in H1. -now apply Zlt_1_l with (- m). +intros n m H1 H2. apply -> (mul_lt_mono_neg_r m) in H1. +apply <- opp_pos_neg in H2. rewrite mul_opp_l, mul_1_l in H1. +now apply lt_1_l with (- m). assumption. Qed. -Theorem Zlt_mul_n1_neg : forall n m : Z, 1 < n -> m < 0 -> n * m < -1. +Theorem lt_mul_n1_neg : forall n m, 1 < n -> m < 0 -> n * m < -1. Proof. -intros n m H1 H2. apply -> (NZmul_lt_mono_neg_r m) in H1. -rewrite Zmul_1_l in H1. now apply Zlt_n1_r with m. +intros n m H1 H2. apply -> (mul_lt_mono_neg_r m) in H1. +rewrite mul_1_l in H1. now apply lt_n1_r with m. assumption. Qed. -Theorem Zlt_mul_n1_pos : forall n m : Z, n < -1 -> 0 < m -> n * m < -1. +Theorem lt_mul_n1_pos : forall n m, n < -1 -> 0 < m -> n * m < -1. Proof. -intros n m H1 H2. apply -> (NZmul_lt_mono_pos_r m) in H1. -rewrite Zmul_opp_l, Zmul_1_l in H1. -apply <- Zopp_neg_pos in H2. now apply Zlt_n1_r with (- m). +intros n m H1 H2. apply -> (mul_lt_mono_pos_r m) in H1. +rewrite mul_opp_l, mul_1_l in H1. +apply <- opp_neg_pos in H2. now apply lt_n1_r with (- m). assumption. Qed. -Theorem Zlt_1_mul_l : forall n m : Z, 1 < n -> n * m < -1 \/ n * m == 0 \/ 1 < n * m. +Theorem lt_1_mul_l : forall n m, 1 < n -> + n * m < -1 \/ n * m == 0 \/ 1 < n * m. Proof. -intros n m H; destruct (Zlt_trichotomy m 0) as [H1 | [H1 | H1]]. -left. now apply Zlt_mul_n1_neg. -right; left; now rewrite H1, Zmul_0_r. -right; right; now apply Zlt_1_mul_pos. +intros n m H; destruct (lt_trichotomy m 0) as [H1 | [H1 | H1]]. +left. now apply lt_mul_n1_neg. +right; left; now rewrite H1, mul_0_r. +right; right; now apply lt_1_mul_pos. Qed. -Theorem Zlt_n1_mul_r : forall n m : Z, n < -1 -> n * m < -1 \/ n * m == 0 \/ 1 < n * m. +Theorem lt_n1_mul_r : forall n m, n < -1 -> + n * m < -1 \/ n * m == 0 \/ 1 < n * m. Proof. -intros n m H; destruct (Zlt_trichotomy m 0) as [H1 | [H1 | H1]]. -right; right. now apply Zlt_1_mul_neg. -right; left; now rewrite H1, Zmul_0_r. -left. now apply Zlt_mul_n1_pos. +intros n m H; destruct (lt_trichotomy m 0) as [H1 | [H1 | H1]]. +right; right. now apply lt_1_mul_neg. +right; left; now rewrite H1, mul_0_r. +left. now apply lt_mul_n1_pos. Qed. -Theorem Zeq_mul_1 : forall n m : Z, n * m == 1 -> n == 1 \/ n == -1. +Theorem eq_mul_1 : forall n m, n * m == 1 -> n == 1 \/ n == -1. Proof. assert (F : ~ 1 < -1). intro H. -assert (H1 : -1 < 0). apply <- Zopp_neg_pos. apply Zlt_succ_diag_r. -assert (H2 : 1 < 0) by now apply Zlt_trans with (-1). false_hyp H2 Znlt_succ_diag_l. -Z0_pos_neg n. -intros m H; rewrite Zmul_0_l in H; false_hyp H Zneq_succ_diag_r. -intros n H; split; apply <- Zle_succ_l in H; le_elim H. -intros m H1; apply (Zlt_1_mul_l n m) in H. +assert (H1 : -1 < 0). apply <- opp_neg_pos. apply lt_succ_diag_r. +assert (H2 : 1 < 0) by now apply lt_trans with (-1). +false_hyp H2 nlt_succ_diag_l. +zero_pos_neg n. +intros m H; rewrite mul_0_l in H; false_hyp H neq_succ_diag_r. +intros n H; split; apply <- le_succ_l in H; le_elim H. +intros m H1; apply (lt_1_mul_l n m) in H. rewrite H1 in H; destruct H as [H | [H | H]]. -false_hyp H F. false_hyp H Zneq_succ_diag_l. false_hyp H Zlt_irrefl. +false_hyp H F. false_hyp H neq_succ_diag_l. false_hyp H lt_irrefl. intros; now left. -intros m H1; apply (Zlt_1_mul_l n m) in H. rewrite Zmul_opp_l in H1; -apply -> Zeq_opp_l in H1. rewrite H1 in H; destruct H as [H | [H | H]]. -false_hyp H Zlt_irrefl. apply -> Zeq_opp_l in H. rewrite Zopp_0 in H. -false_hyp H Zneq_succ_diag_l. false_hyp H F. -intros; right; symmetry; now apply Zopp_wd. +intros m H1; apply (lt_1_mul_l n m) in H. rewrite mul_opp_l in H1; +apply -> eq_opp_l in H1. rewrite H1 in H; destruct H as [H | [H | H]]. +false_hyp H lt_irrefl. apply -> eq_opp_l in H. rewrite opp_0 in H. +false_hyp H neq_succ_diag_l. false_hyp H F. +intros; right; symmetry; now apply opp_wd. Qed. -Theorem Zlt_mul_diag_l : forall n m : Z, n < 0 -> (1 < m <-> n * m < n). +Theorem lt_mul_diag_l : forall n m, n < 0 -> (1 < m <-> n * m < n). Proof. -intros n m H. stepr (n * m < n * 1) by now rewrite Zmul_1_r. -now apply Zmul_lt_mono_neg_l. +intros n m H. stepr (n * m < n * 1) by now rewrite mul_1_r. +now apply mul_lt_mono_neg_l. Qed. -Theorem Zlt_mul_diag_r : forall n m : Z, 0 < n -> (1 < m <-> n < n * m). +Theorem lt_mul_diag_r : forall n m, 0 < n -> (1 < m <-> n < n * m). Proof. -intros n m H. stepr (n * 1 < n * m) by now rewrite Zmul_1_r. -now apply Zmul_lt_mono_pos_l. +intros n m H. stepr (n * 1 < n * m) by now rewrite mul_1_r. +now apply mul_lt_mono_pos_l. Qed. -Theorem Zle_mul_diag_l : forall n m : Z, n < 0 -> (1 <= m <-> n * m <= n). +Theorem le_mul_diag_l : forall n m, n < 0 -> (1 <= m <-> n * m <= n). Proof. -intros n m H. stepr (n * m <= n * 1) by now rewrite Zmul_1_r. -now apply Zmul_le_mono_neg_l. +intros n m H. stepr (n * m <= n * 1) by now rewrite mul_1_r. +now apply mul_le_mono_neg_l. Qed. -Theorem Zle_mul_diag_r : forall n m : Z, 0 < n -> (1 <= m <-> n <= n * m). +Theorem le_mul_diag_r : forall n m, 0 < n -> (1 <= m <-> n <= n * m). Proof. -intros n m H. stepr (n * 1 <= n * m) by now rewrite Zmul_1_r. -now apply Zmul_le_mono_pos_l. +intros n m H. stepr (n * 1 <= n * m) by now rewrite mul_1_r. +now apply mul_le_mono_pos_l. Qed. -Theorem Zlt_mul_r : forall n m p : Z, 0 < n -> 1 < p -> n < m -> n < m * p. +Theorem lt_mul_r : forall n m p, 0 < n -> 1 < p -> n < m -> n < m * p. Proof. -intros. stepl (n * 1) by now rewrite Zmul_1_r. -apply Zmul_lt_mono_nonneg. -now apply Zlt_le_incl. assumption. apply Zle_0_1. assumption. +intros. stepl (n * 1) by now rewrite mul_1_r. +apply mul_lt_mono_nonneg. +now apply lt_le_incl. assumption. apply le_0_1. assumption. Qed. End ZMulOrderPropFunct. diff --git a/theories/Numbers/Integer/Abstract/ZProperties.v b/theories/Numbers/Integer/Abstract/ZProperties.v new file mode 100644 index 000000000..eee5b0273 --- /dev/null +++ b/theories/Numbers/Integer/Abstract/ZProperties.v @@ -0,0 +1,18 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) +(* \VV/ **************************************************************) +(* // * This file is distributed under the terms of the *) +(* * GNU Lesser General Public License Version 2.1 *) +(************************************************************************) + +(*i $Id$ i*) + +Require Export ZAxioms ZMulOrder. + +(** This functor summarizes all known facts about Z. + For the moment it is only an alias to [ZMulOrderPropFunct], which + subsumes all others. +*) + +Module ZPropFunct := ZMulOrderPropFunct. diff --git a/theories/Numbers/Integer/BigZ/BigZ.v b/theories/Numbers/Integer/BigZ/BigZ.v index f7c423ebb..6e8ca37ca 100644 --- a/theories/Numbers/Integer/BigZ/BigZ.v +++ b/theories/Numbers/Integer/BigZ/BigZ.v @@ -11,7 +11,7 @@ (*i $Id$ i*) Require Export BigN. -Require Import ZMulOrder. +Require Import ZProperties. Require Import ZSig. Require Import ZSigZAxioms. Require Import ZMake. @@ -21,7 +21,7 @@ Module BigZ <: ZType := ZMake.Make BigN. (** Module [BigZ] implements [ZAxiomsSig] *) Module Export BigZAxiomsMod := ZSig_ZAxioms BigZ. -Module Export BigZMulOrderPropMod := ZMulOrderPropFunct BigZAxiomsMod. +Module Export BigZPropMod := ZPropFunct BigZAxiomsMod. (** Notations about [BigZ] *) @@ -32,7 +32,7 @@ Bind Scope bigZ_scope with bigZ. Bind Scope bigZ_scope with BigZ.t. Bind Scope bigZ_scope with BigZ.t_. -Notation Local "0" := BigZ.zero : bigZ_scope. +Local Notation "0" := BigZ.zero : bigZ_scope. Infix "+" := BigZ.add : bigZ_scope. Infix "-" := BigZ.sub : bigZ_scope. Notation "- x" := (BigZ.opp x) : bigZ_scope. @@ -93,13 +93,13 @@ Lemma BigZring : ring_theory BigZ.zero BigZ.one BigZ.add BigZ.mul BigZ.sub BigZ.opp BigZ.eq. Proof. constructor. -exact Zadd_0_l. -exact Zadd_comm. -exact Zadd_assoc. -exact Zmul_1_l. -exact Zmul_comm. -exact Zmul_assoc. -exact Zmul_add_distr_r. +exact add_0_l. +exact add_comm. +exact add_assoc. +exact mul_1_l. +exact mul_comm. +exact mul_assoc. +exact mul_add_distr_r. exact sub_opp. exact add_opp. Qed. diff --git a/theories/Numbers/Integer/Binary/ZBinary.v b/theories/Numbers/Integer/Binary/ZBinary.v index 9b55c771c..0d8f8bf5d 100644 --- a/theories/Numbers/Integer/Binary/ZBinary.v +++ b/theories/Numbers/Integer/Binary/ZBinary.v @@ -10,163 +10,86 @@ (*i $Id$ i*) -Require Import ZMulOrder. + +Require Import ZAxioms ZProperties. Require Import ZArith. -Open Local Scope Z_scope. +Local Open Scope Z_scope. + +(** * Implementation of [ZAxiomsSig] by [BinInt.Z] *) Module ZBinAxiomsMod <: ZAxiomsSig. -Module Export NZOrdAxiomsMod <: NZOrdAxiomsSig. -Module Export NZAxiomsMod <: NZAxiomsSig. - -Definition NZ := Z. -Definition NZeq := (@eq Z). -Definition NZ0 := 0. -Definition NZsucc := Zsucc'. -Definition NZpred := Zpred'. -Definition NZadd := Zplus. -Definition NZsub := Zminus. -Definition NZmul := Zmult. - -Instance NZeq_equiv : Equivalence NZeq. -Program Instance NZsucc_wd : Proper (eq==>eq) NZsucc. -Program Instance NZpred_wd : Proper (eq==>eq) NZpred. -Program Instance NZadd_wd : Proper (eq==>eq==>eq) NZadd. -Program Instance NZsub_wd : Proper (eq==>eq==>eq) NZsub. -Program Instance NZmul_wd : Proper (eq==>eq==>eq) NZmul. - -Theorem NZpred_succ : forall n : Z, NZpred (NZsucc n) = n. -Proof. -exact Zpred'_succ'. -Qed. -Theorem NZinduction : - forall A : Z -> Prop, Proper (NZeq ==> iff) A -> - A 0 -> (forall n : Z, A n <-> A (NZsucc n)) -> forall n : Z, A n. +(** Bi-directional induction. *) + +Theorem bi_induction : + forall A : Z -> Prop, Proper (eq ==> iff) A -> + A 0 -> (forall n : Z, A n <-> A (Zsucc n)) -> forall n : Z, A n. Proof. intros A A_wd A0 AS n; apply Zind; clear n. assumption. -intros; now apply -> AS. -intros n H. rewrite <- (Zsucc'_pred' n) in H. now apply <- AS. -Qed. - -Theorem NZadd_0_l : forall n : Z, 0 + n = n. -Proof. -exact Zplus_0_l. -Qed. - -Theorem NZadd_succ_l : forall n m : Z, (NZsucc n) + m = NZsucc (n + m). -Proof. -intros; do 2 rewrite <- Zsucc_succ'; apply Zplus_succ_l. -Qed. - -Theorem NZsub_0_r : forall n : Z, n - 0 = n. -Proof. -exact Zminus_0_r. -Qed. - -Theorem NZsub_succ_r : forall n m : Z, n - (NZsucc m) = NZpred (n - m). -Proof. -intros; rewrite <- Zsucc_succ'; rewrite <- Zpred_pred'; -apply Zminus_succ_r. -Qed. - -Theorem NZmul_0_l : forall n : Z, 0 * n = 0. -Proof. -reflexivity. -Qed. - -Theorem NZmul_succ_l : forall n m : Z, (NZsucc n) * m = n * m + m. -Proof. -intros; rewrite <- Zsucc_succ'; apply Zmult_succ_l. -Qed. - -End NZAxiomsMod. - -Definition NZlt := Zlt. -Definition NZle := Zle. -Definition NZmin := Zmin. -Definition NZmax := Zmax. - -Program Instance NZlt_wd : Proper (eq==>eq==>iff) NZlt. -Program Instance NZle_wd : Proper (eq==>eq==>iff) NZle. -Program Instance NZmin_wd : Proper (eq==>eq==>eq) NZmin. -Program Instance NZmax_wd : Proper (eq==>eq==>eq) NZmax. - -Theorem NZlt_eq_cases : forall n m : Z, n <= m <-> n < m \/ n = m. -Proof. -intros n m; split. apply Zle_lt_or_eq. -intro H; destruct H as [H | H]. now apply Zlt_le_weak. rewrite H; apply Zle_refl. +intros; rewrite <- Zsucc_succ'. now apply -> AS. +intros n H. rewrite <- Zpred_pred'. rewrite Zsucc_pred in H. now apply <- AS. Qed. -Theorem NZlt_irrefl : forall n : Z, ~ n < n. -Proof. -exact Zlt_irrefl. -Qed. +(** Basic operations. *) -Theorem NZlt_succ_r : forall n m : Z, n < (NZsucc m) <-> n <= m. -Proof. -intros; unfold NZsucc; rewrite <- Zsucc_succ'; split; -[apply Zlt_succ_le | apply Zle_lt_succ]. -Qed. +Instance eq_equiv : Equivalence (@eq Z). +Program Instance succ_wd : Proper (eq==>eq) Zsucc. +Program Instance pred_wd : Proper (eq==>eq) Zpred. +Program Instance add_wd : Proper (eq==>eq==>eq) Zplus. +Program Instance sub_wd : Proper (eq==>eq==>eq) Zminus. +Program Instance mul_wd : Proper (eq==>eq==>eq) Zmult. -Theorem NZmin_l : forall n m : NZ, n <= m -> NZmin n m = n. -Proof. -unfold NZmin, Zmin, Zle; intros n m H. -destruct (n ?= m); try reflexivity. now elim H. -Qed. +Definition pred_succ n := eq_sym (Zpred_succ n). +Definition add_0_l := Zplus_0_l. +Definition add_succ_l := Zplus_succ_l. +Definition sub_0_r := Zminus_0_r. +Definition sub_succ_r := Zminus_succ_r. +Definition mul_0_l := Zmult_0_l. +Definition mul_succ_l := Zmult_succ_l. -Theorem NZmin_r : forall n m : NZ, m <= n -> NZmin n m = m. -Proof. -unfold NZmin, Zmin, Zle; intros n m H. -case_eq (n ?= m); intro H1; try reflexivity. -now apply Zcompare_Eq_eq. -apply <- Zcompare_Gt_Lt_antisym in H1. now elim H. -Qed. +(** Order *) -Theorem NZmax_l : forall n m : NZ, m <= n -> NZmax n m = n. -Proof. -unfold NZmax, Zmax, Zle; intros n m H. -case_eq (n ?= m); intro H1; try reflexivity. -apply <- Zcompare_Gt_Lt_antisym in H1. now elim H. -Qed. +Program Instance lt_wd : Proper (eq==>eq==>iff) Zlt. -Theorem NZmax_r : forall n m : NZ, n <= m -> NZmax n m = m. -Proof. -unfold NZmax, Zmax, Zle; intros n m H. -case_eq (n ?= m); intro H1. -now apply Zcompare_Eq_eq. reflexivity. now elim H. -Qed. +Definition lt_eq_cases := Zle_lt_or_eq_iff. +Definition lt_irrefl := Zlt_irrefl. +Definition lt_succ_r := Zlt_succ_r. -End NZOrdAxiomsMod. +Definition min_l := Zmin_l. +Definition min_r := Zmin_r. +Definition max_l := Zmax_l. +Definition max_r := Zmax_r. -Definition Zopp (x : Z) := -match x with -| Z0 => Z0 -| Zpos x => Zneg x -| Zneg x => Zpos x -end. +(** Properties specific to integers, not natural numbers. *) -Program Instance Zopp_wd : Proper (eq==>eq) Zopp. +Program Instance opp_wd : Proper (eq==>eq) Zopp. -Theorem Zsucc_pred : forall n : Z, NZsucc (NZpred n) = n. -Proof. -exact Zsucc'_pred'. -Qed. +Definition succ_pred n := eq_sym (Zsucc_pred n). +Definition opp_0 := Zopp_0. +Definition opp_succ := Zopp_succ. -Theorem Zopp_0 : - 0 = 0. -Proof. -reflexivity. -Qed. +(** The instantiation of operations. + Placing them at the very end avoids having indirections in above lemmas. *) -Theorem Zopp_succ : forall n : Z, - (NZsucc n) = NZpred (- n). -Proof. -intro; rewrite <- Zsucc_succ'; rewrite <- Zpred_pred'. apply Zopp_succ. -Qed. +Definition t := Z. +Definition eq := (@eq Z). +Definition zero := 0. +Definition succ := Zsucc. +Definition pred := Zpred. +Definition add := Zplus. +Definition sub := Zminus. +Definition mul := Zmult. +Definition lt := Zlt. +Definition le := Zle. +Definition min := Zmin. +Definition max := Zmax. +Definition opp := Zopp. End ZBinAxiomsMod. -Module Export ZBinMulOrderPropMod := ZMulOrderPropFunct ZBinAxiomsMod. +Module Export ZBinPropMod := ZPropFunct ZBinAxiomsMod. (** Z forms a ring *) diff --git a/theories/Numbers/Integer/NatPairs/ZNatPairs.v b/theories/Numbers/Integer/NatPairs/ZNatPairs.v index dcda3f1e5..0956f337f 100644 --- a/theories/Numbers/Integer/NatPairs/ZNatPairs.v +++ b/theories/Numbers/Integer/NatPairs/ZNatPairs.v @@ -10,195 +10,150 @@ (*i $Id$ i*) -Require Import NSub. (* The most complete file for natural numbers *) -Require Export ZMulOrder. (* The most complete file for integers *) +Require Import NProperties. (* The most complete file for N *) +Require Export ZProperties. (* The most complete file for Z *) Require Export Ring. -Module ZPairsAxiomsMod (Import NAxiomsMod : NAxiomsSig) <: ZAxiomsSig. -Module Import NPropMod := NSubPropFunct NAxiomsMod. (* Get all properties of natural numbers *) - -(* We do not declare ring in Natural/Abstract for two reasons. First, some -of the properties proved in NAdd and NMul are used in the new BinNat, -and it is in turn used in Ring. Using ring in Natural/Abstract would be -circular. It is possible, however, not to make BinNat dependent on -Numbers/Natural and prove the properties necessary for ring from scratch -(this is, of course, how it used to be). In addition, if we define semiring -structures in the implementation subdirectories of Natural, we are able to -specify binary natural numbers as the type of coefficients. For these -reasons we define an abstract semiring here. *) - -Open Local Scope NatScope. - -Lemma Nsemi_ring : semi_ring_theory 0 1 add mul Neq. -Proof. -constructor. -exact add_0_l. -exact add_comm. -exact add_assoc. -exact mul_1_l. -exact mul_0_l. -exact mul_comm. -exact mul_assoc. -exact mul_add_distr_r. -Qed. - -Add Ring NSR : Nsemi_ring. - -(* The definitions of functions (NZadd, NZmul, etc.) will be unfolded by -the properties functor. Since we don't want Zadd_comm to refer to unfolded -definitions of equality: fun p1 p2 : NZ => (fst p1 + snd p2) = (fst p2 + snd p1), -we will provide an extra layer of definitions. *) - -Definition Z := (N * N)%type. -Definition Z0 : Z := (0, 0). -Definition Zeq (p1 p2 : Z) := ((fst p1) + (snd p2) == (fst p2) + (snd p1)). -Definition Zsucc (n : Z) : Z := (S (fst n), snd n). -Definition Zpred (n : Z) : Z := (fst n, S (snd n)). - -(* We do not have Zpred (Zsucc n) = n but only Zpred (Zsucc n) == n. It -could be possible to consider as canonical only pairs where one of the -elements is 0, and make all operations convert canonical values into other -canonical values. In that case, we could get rid of setoids and arrive at -integers as signed natural numbers. *) - -Definition Zadd (n m : Z) : Z := ((fst n) + (fst m), (snd n) + (snd m)). -Definition Zsub (n m : Z) : Z := ((fst n) + (snd m), (snd n) + (fst m)). - -(* Unfortunately, the elements of the pair keep increasing, even during -subtraction *) - -Definition Zmul (n m : Z) : Z := - ((fst n) * (fst m) + (snd n) * (snd m), (fst n) * (snd m) + (snd n) * (fst m)). -Definition Zlt (n m : Z) := (fst n) + (snd m) < (fst m) + (snd n). -Definition Zle (n m : Z) := (fst n) + (snd m) <= (fst m) + (snd n). -Definition Zmin (n m : Z) := (min ((fst n) + (snd m)) ((fst m) + (snd n)), (snd n) + (snd m)). -Definition Zmax (n m : Z) := (max ((fst n) + (snd m)) ((fst m) + (snd n)), (snd n) + (snd m)). +Notation "s #1" := (fst s) (at level 9, format "s '#1'") : pair_scope. +Notation "s #2" := (snd s) (at level 9, format "s '#2'") : pair_scope. +Open Local Scope pair_scope. + +Module ZPairsAxiomsMod (Import N : NAxiomsSig) <: ZAxiomsSig. +Module Import NPropMod := NPropFunct N. (* Get all properties of N *) + +Local Open Scope NumScope. + +(** The definitions of functions ([add], [mul], etc.) will be unfolded + by the properties functor. Since we don't want [add_comm] to refer + to unfolded definitions of equality: [fun p1 p2 => (fst p1 + + snd p2) = (fst p2 + snd p1)], we will provide an extra layer of + definitions. *) + +Module Z. + +Definition t := (N.t * N.t)%type. +Definition zero : t := (0, 0). +Definition eq (p q : t) := (p#1 + q#2 == q#1 + p#2). +Definition succ (n : t) : t := (S n#1, n#2). +Definition pred (n : t) : t := (n#1, S n#2). +Definition opp (n : t) : t := (n#2, n#1). +Definition add (n m : t) : t := (n#1 + m#1, n#2 + m#2). +Definition sub (n m : t) : t := (n#1 + m#2, n#2 + m#1). +Definition mul (n m : t) : t := + (n#1 * m#1 + n#2 * m#2, n#1 * m#2 + n#2 * m#1). +Definition lt (n m : t) := n#1 + m#2 < m#1 + n#2. +Definition le (n m : t) := n#1 + m#2 <= m#1 + n#2. +Definition min (n m : t) : t := (min (n#1 + m#2) (m#1 + n#2), n#2 + m#2). +Definition max (n m : t) : t := (max (n#1 + m#2) (m#1 + n#2), n#2 + m#2). + +(** NB : We do not have [Zpred (Zsucc n) = n] but only [Zpred (Zsucc n) == n]. + It could be possible to consider as canonical only pairs where + one of the elements is 0, and make all operations convert + canonical values into other canonical values. In that case, we + could get rid of setoids and arrive at integers as signed natural + numbers. *) + +(** NB : Unfortunately, the elements of the pair keep increasing during + many operations, even during subtraction. *) + +End Z. Delimit Scope IntScope with Int. -Bind Scope IntScope with Z. -Notation "x == y" := (Zeq x y) (at level 70) : IntScope. -Notation "x ~= y" := (~ Zeq x y) (at level 70) : IntScope. -Notation "0" := Z0 : IntScope. -Notation "1" := (Zsucc Z0) : IntScope. -Notation "x + y" := (Zadd x y) : IntScope. -Notation "x - y" := (Zsub x y) : IntScope. -Notation "x * y" := (Zmul x y) : IntScope. -Notation "x < y" := (Zlt x y) : IntScope. -Notation "x <= y" := (Zle x y) : IntScope. -Notation "x > y" := (Zlt y x) (only parsing) : IntScope. -Notation "x >= y" := (Zle y x) (only parsing) : IntScope. - -Notation Local N := NZ. -(* To remember N without having to use a long qualifying name. since NZ will be redefined *) -Notation Local NE := NZeq (only parsing). -Notation Local add_wd := NZadd_wd (only parsing). - -Module Export NZOrdAxiomsMod <: NZOrdAxiomsSig. -Module Export NZAxiomsMod <: NZAxiomsSig. - -Definition NZ : Type := Z. -Definition NZeq := Zeq. -Definition NZ0 := Z0. -Definition NZsucc := Zsucc. -Definition NZpred := Zpred. -Definition NZadd := Zadd. -Definition NZsub := Zsub. -Definition NZmul := Zmul. - -Theorem ZE_refl : reflexive Z Zeq. -Proof. -unfold reflexive, Zeq. reflexivity. -Qed. +Bind Scope IntScope with Z.t. +Notation "x == y" := (Z.eq x y) (at level 70) : IntScope. +Notation "x ~= y" := (~ Z.eq x y) (at level 70) : IntScope. +Notation "0" := Z.zero : IntScope. +Notation "1" := (Z.succ Z.zero) : IntScope. +Notation "x + y" := (Z.add x y) : IntScope. +Notation "x - y" := (Z.sub x y) : IntScope. +Notation "x * y" := (Z.mul x y) : IntScope. +Notation "- x" := (Z.opp x) : IntScope. +Notation "x < y" := (Z.lt x y) : IntScope. +Notation "x <= y" := (Z.le x y) : IntScope. +Notation "x > y" := (Z.lt y x) (only parsing) : IntScope. +Notation "x >= y" := (Z.le y x) (only parsing) : IntScope. + +Lemma sub_add_opp : forall n m, Z.sub n m = Z.add n (Z.opp m). +Proof. reflexivity. Qed. -Theorem ZE_sym : symmetric Z Zeq. +Instance eq_equiv : Equivalence Z.eq. Proof. -unfold symmetric, Zeq; now symmetry. +split. +unfold Reflexive, Z.eq. reflexivity. +unfold Symmetric, Z.eq; now symmetry. +unfold Transitive, Z.eq. intros (n1,n2) (m1,m2) (p1,p2) H1 H2; simpl in *. +apply (add_cancel_r _ _ (m1+m2)). +rewrite add_shuffle2, H1, add_shuffle1, H2. +now rewrite add_shuffle1, (add_comm m1). Qed. -Theorem ZE_trans : transitive Z Zeq. +Instance pair_wd : Proper (N.eq==>N.eq==>Z.eq) (@pair N.t N.t). Proof. -unfold transitive, Zeq. intros n m p H1 H2. -assert (H3 : (fst n + snd m) + (fst m + snd p) == (fst m + snd n) + (fst p + snd m)) -by now apply add_wd. -stepl ((fst n + snd p) + (fst m + snd m)) in H3 by ring. -stepr ((fst p + snd n) + (fst m + snd m)) in H3 by ring. -now apply -> add_cancel_r in H3. +intros n1 n2 H1 m1 m2 H2; unfold Z.eq; simpl; now rewrite H1, H2. Qed. -Instance NZeq_equiv : Equivalence Zeq. +Instance succ_wd : Proper (Z.eq ==> Z.eq) Z.succ. Proof. -split; [apply ZE_refl | apply ZE_sym | apply ZE_trans]. +unfold Z.succ, Z.eq; intros n m H; simpl. +do 2 rewrite add_succ_l; now rewrite H. Qed. -Instance Zpair_wd : Proper (NE==>NE==>Zeq) (@pair N N). +Instance pred_wd : Proper (Z.eq ==> Z.eq) Z.pred. Proof. -intros n1 n2 H1 m1 m2 H2; unfold Zeq; simpl; rewrite H1; now rewrite H2. +unfold Z.pred, Z.eq; intros n m H; simpl. +do 2 rewrite add_succ_r; now rewrite H. Qed. -Instance NZsucc_wd : Proper (Zeq ==> Zeq) NZsucc. +Instance add_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.add. Proof. -unfold NZsucc, Zeq; intros n m H; simpl. -do 2 rewrite add_succ_l; now rewrite H. +unfold Z.eq, Z.add; intros n1 m1 H1 n2 m2 H2; simpl. +now rewrite add_shuffle1, H1, H2, add_shuffle1. Qed. -Instance NZpred_wd : Proper (Zeq ==> Zeq) NZpred. +Instance opp_wd : Proper (Z.eq ==> Z.eq) Z.opp. Proof. -unfold NZpred, Zeq; intros n m H; simpl. -do 2 rewrite add_succ_r; now rewrite H. +unfold Z.eq, Z.opp; intros (n1,n2) (m1,m2) H; simpl in *. +now rewrite (add_comm n2), (add_comm m2). Qed. -Instance NZadd_wd : Proper (Zeq ==> Zeq ==> Zeq) NZadd. +Instance sub_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.sub. Proof. -unfold Zeq, NZadd; intros n1 m1 H1 n2 m2 H2; simpl. -assert (H3 : (fst n1 + snd m1) + (fst n2 + snd m2) == (fst m1 + snd n1) + (fst m2 + snd n2)) -by now apply add_wd. -stepl (fst n1 + snd m1 + (fst n2 + snd m2)) by ring. -now stepr (fst m1 + snd n1 + (fst m2 + snd n2)) by ring. +intros n1 m1 H1 n2 m2 H2. rewrite 2 sub_add_opp. +apply add_wd, opp_wd; auto. Qed. -Instance NZsub_wd : Proper (Zeq ==> Zeq ==> Zeq) NZsub. +Lemma mul_comm : forall n m, (n*m == m*n)%Int. Proof. -unfold Zeq, NZsub; intros n1 m1 H1 n2 m2 H2; simpl. -symmetry in H2. -assert (H3 : (fst n1 + snd m1) + (fst m2 + snd n2) == (fst m1 + snd n1) + (fst n2 + snd m2)) -by now apply add_wd. -stepl (fst n1 + snd m1 + (fst m2 + snd n2)) by ring. -now stepr (fst m1 + snd n1 + (fst n2 + snd m2)) by ring. +intros (n1,n2) (m1,m2); compute. +rewrite (add_comm (m1*n2)). +apply N.add_wd; apply N.add_wd; apply mul_comm. Qed. -Instance NZmul_wd : Proper (Zeq ==> Zeq ==> Zeq) NZmul. +Instance mul_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.mul. Proof. -unfold NZmul, Zeq; intros n1 m1 H1 n2 m2 H2; simpl. -stepl (fst n1 * fst n2 + (snd n1 * snd n2 + fst m1 * snd m2 + snd m1 * fst m2)) by ring. -stepr (fst n1 * snd n2 + (fst m1 * fst m2 + snd m1 * snd m2 + snd n1 * fst n2)) by ring. -apply add_mul_repl_pair with (n := fst m2) (m := snd m2); [| now idtac]. -stepl (snd n1 * snd n2 + (fst n1 * fst m2 + fst m1 * snd m2 + snd m1 * fst m2)) by ring. -stepr (snd n1 * fst n2 + (fst n1 * snd m2 + fst m1 * fst m2 + snd m1 * snd m2)) by ring. -apply add_mul_repl_pair with (n := snd m2) (m := fst m2); -[| (stepl (fst n2 + snd m2) by ring); now stepr (fst m2 + snd n2) by ring]. -stepl (snd m2 * snd n1 + (fst n1 * fst m2 + fst m1 * snd m2 + snd m1 * fst m2)) by ring. -stepr (snd m2 * fst n1 + (snd n1 * fst m2 + fst m1 * fst m2 + snd m1 * snd m2)) by ring. -apply add_mul_repl_pair with (n := snd m1) (m := fst m1); -[ | (stepl (fst n1 + snd m1) by ring); now stepr (fst m1 + snd n1) by ring]. -stepl (fst m2 * fst n1 + (snd m2 * snd m1 + fst m1 * snd m2 + snd m1 * fst m2)) by ring. -stepr (fst m2 * snd n1 + (snd m2 * fst m1 + fst m1 * fst m2 + snd m1 * snd m2)) by ring. -apply add_mul_repl_pair with (n := fst m1) (m := snd m1); [| now idtac]. -ring. +assert (forall n, Proper (Z.eq ==> Z.eq) (Z.mul n)). + unfold Z.mul, Z.eq. intros (n1,n2) (p1,p2) (q1,q2) H; simpl in *. + rewrite add_shuffle1, (add_comm (n1*p1)). + symmetry. rewrite add_shuffle1. + rewrite <- ! mul_add_distr_l. + rewrite (add_comm p2), (add_comm q2), H. + reflexivity. +intros n n' Hn m m' Hm. +rewrite Hm, (mul_comm n), (mul_comm n'), Hn. +reflexivity. Qed. Section Induction. -Open Scope NatScope. (* automatically closes at the end of the section *) -Variable A : Z -> Prop. -Hypothesis A_wd : Proper (Zeq==>iff) A. +Variable A : Z.t -> Prop. +Hypothesis A_wd : Proper (Z.eq==>iff) A. -Theorem NZinduction : - A 0 -> (forall n : Z, A n <-> A (Zsucc n)) -> forall n : Z, A n. - (* 0 is interpreted as in Z due to "Bind" directive *) +Theorem bi_induction : + A 0 -> (forall n, A n <-> A (Z.succ n)) -> forall n, A n. Proof. -intros A0 AS n; unfold NZ0, Zsucc, Zeq in *. +intros A0 AS n; unfold Z.zero, Z.succ, Z.eq in *. destruct n as [n m]. -cut (forall p : N, A (p, 0)); [intro H1 |]. -cut (forall p : N, A (0, p)); [intro H2 |]. +cut (forall p, A (p, 0)); [intro H1 |]. +cut (forall p, A (0, p)); [intro H2 |]. destruct (add_dichotomy n m) as [[p H] | [p H]]. rewrite (A_wd (n, m) (0, p)) by (rewrite add_0_l; now rewrite add_comm). apply H2. @@ -215,183 +170,136 @@ End Induction. (* Time to prove theorems in the language of Z *) -Open Local Scope IntScope. +Open Scope IntScope. -Theorem NZpred_succ : forall n : Z, Zpred (Zsucc n) == n. +Theorem pred_succ : forall n, Z.pred (Z.succ n) == n. Proof. -unfold NZpred, NZsucc, Zeq; intro n; simpl. -rewrite add_succ_l; now rewrite add_succ_r. +unfold Z.pred, Z.succ, Z.eq; intro n; simpl; now nzsimpl. Qed. -Theorem NZadd_0_l : forall n : Z, 0 + n == n. +Theorem succ_pred : forall n, Z.succ (Z.pred n) == n. Proof. -intro n; unfold NZadd, Zeq; simpl. now do 2 rewrite add_0_l. +intro n; unfold Z.succ, Z.pred, Z.eq; simpl; now nzsimpl. Qed. -Theorem NZadd_succ_l : forall n m : Z, (Zsucc n) + m == Zsucc (n + m). +Theorem opp_0 : - 0 == 0. Proof. -intros n m; unfold NZadd, Zeq; simpl. now do 2 rewrite add_succ_l. +unfold Z.opp, Z.eq; simpl. now nzsimpl. Qed. -Theorem NZsub_0_r : forall n : Z, n - 0 == n. +Theorem opp_succ : forall n, - (Z.succ n) == Z.pred (- n). Proof. -intro n; unfold NZsub, Zeq; simpl. now do 2 rewrite add_0_r. +reflexivity. Qed. -Theorem NZsub_succ_r : forall n m : Z, n - (Zsucc m) == Zpred (n - m). +Theorem add_0_l : forall n, 0 + n == n. Proof. -intros n m; unfold NZsub, Zeq; simpl. symmetry; now rewrite add_succ_r. +intro n; unfold Z.add, Z.eq; simpl. now nzsimpl. Qed. -Theorem NZmul_0_l : forall n : Z, 0 * n == 0. +Theorem add_succ_l : forall n m, (Z.succ n) + m == Z.succ (n + m). Proof. -intro n; unfold NZmul, Zeq; simpl. -repeat rewrite mul_0_l. now rewrite add_assoc. +intros n m; unfold Z.add, Z.eq; simpl. now nzsimpl. Qed. -Theorem NZmul_succ_l : forall n m : Z, (Zsucc n) * m == n * m + m. +Theorem sub_0_r : forall n, n - 0 == n. Proof. -intros n m; unfold NZmul, NZsucc, Zeq; simpl. -do 2 rewrite mul_succ_l. ring. +intro n; unfold Z.sub, Z.eq; simpl. now nzsimpl. Qed. -End NZAxiomsMod. - -Definition NZlt := Zlt. -Definition NZle := Zle. -Definition NZmin := Zmin. -Definition NZmax := Zmax. - -Instance NZlt_wd : Proper (Zeq ==> Zeq ==> iff) NZlt. +Theorem sub_succ_r : forall n m, n - (Z.succ m) == Z.pred (n - m). Proof. -unfold NZlt, Zlt, Zeq; intros n1 m1 H1 n2 m2 H2; simpl. split; intro H. -stepr (snd m1 + fst m2) by apply add_comm. -apply (add_lt_repl_pair (fst n1) (snd n1)); [| assumption]. -stepl (snd m2 + fst n1) by apply add_comm. -stepr (fst m2 + snd n1) by apply add_comm. -apply (add_lt_repl_pair (snd n2) (fst n2)). -now stepl (fst n1 + snd n2) by apply add_comm. -stepl (fst m2 + snd n2) by apply add_comm. now stepr (fst n2 + snd m2) by apply add_comm. -stepr (snd n1 + fst n2) by apply add_comm. -apply (add_lt_repl_pair (fst m1) (snd m1)); [| now symmetry]. -stepl (snd n2 + fst m1) by apply add_comm. -stepr (fst n2 + snd m1) by apply add_comm. -apply (add_lt_repl_pair (snd m2) (fst m2)). -now stepl (fst m1 + snd m2) by apply add_comm. -stepl (fst n2 + snd m2) by apply add_comm. now stepr (fst m2 + snd n2) by apply add_comm. +intros n m; unfold Z.sub, Z.eq; simpl. symmetry; now rewrite add_succ_r. Qed. -Instance NZle_wd : Proper (Zeq ==> Zeq ==> iff) NZle. +Theorem mul_0_l : forall n, 0 * n == 0. Proof. -unfold NZle, Zle, Zeq; intros n1 m1 H1 n2 m2 H2; simpl. -do 2 rewrite lt_eq_cases. rewrite (NZlt_wd n1 m1 H1 n2 m2 H2). fold (m1 < m2)%Int. -fold (n1 == n2)%Int (m1 == m2)%Int; fold (n1 == m1)%Int in H1; fold (n2 == m2)%Int in H2. -now rewrite H1, H2. +intros (n1,n2); unfold Z.mul, Z.eq; simpl; now nzsimpl. Qed. -Instance NZmin_wd : Proper (Zeq ==> Zeq ==> Zeq) NZmin. +Theorem mul_succ_l : forall n m, (Z.succ n) * m == n * m + m. Proof. -intros n1 m1 H1 n2 m2 H2; unfold NZmin, Zeq; simpl. -destruct (le_ge_cases (fst n1 + snd n2) (fst n2 + snd n1)) as [H | H]. -rewrite (min_l (fst n1 + snd n2) (fst n2 + snd n1)) by assumption. -rewrite (min_l (fst m1 + snd m2) (fst m2 + snd m1)) by -now apply -> (NZle_wd n1 m1 H1 n2 m2 H2). -stepl ((fst n1 + snd m1) + (snd n2 + snd m2)) by ring. -unfold Zeq in H1. rewrite H1. ring. -rewrite (min_r (fst n1 + snd n2) (fst n2 + snd n1)) by assumption. -rewrite (min_r (fst m1 + snd m2) (fst m2 + snd m1)) by -now apply -> (NZle_wd n2 m2 H2 n1 m1 H1). -stepl ((fst n2 + snd m2) + (snd n1 + snd m1)) by ring. -unfold Zeq in H2. rewrite H2. ring. +intros (n1,n2) (m1,m2); unfold Z.mul, Z.succ, Z.eq; simpl; nzsimpl. +rewrite <- (add_assoc _ m1), (add_comm m1), (add_assoc _ _ m1). +now rewrite <- (add_assoc _ m2), (add_comm m2), (add_assoc _ (n2*m1)%Num m2). Qed. -Instance NZmax_wd : Proper (Zeq ==> Zeq ==> Zeq) NZmax. -Proof. -intros n1 m1 H1 n2 m2 H2; unfold NZmax, Zeq; simpl. -destruct (le_ge_cases (fst n1 + snd n2) (fst n2 + snd n1)) as [H | H]. -rewrite (max_r (fst n1 + snd n2) (fst n2 + snd n1)) by assumption. -rewrite (max_r (fst m1 + snd m2) (fst m2 + snd m1)) by -now apply -> (NZle_wd n1 m1 H1 n2 m2 H2). -stepl ((fst n2 + snd m2) + (snd n1 + snd m1)) by ring. -unfold Zeq in H2. rewrite H2. ring. -rewrite (max_l (fst n1 + snd n2) (fst n2 + snd n1)) by assumption. -rewrite (max_l (fst m1 + snd m2) (fst m2 + snd m1)) by -now apply -> (NZle_wd n2 m2 H2 n1 m1 H1). -stepl ((fst n1 + snd m1) + (snd n2 + snd m2)) by ring. -unfold Zeq in H1. rewrite H1. ring. -Qed. - -Open Local Scope IntScope. - -Theorem NZlt_eq_cases : forall n m : Z, n <= m <-> n < m \/ n == m. -Proof. -intros n m; unfold Zlt, Zle, Zeq; simpl. apply lt_eq_cases. -Qed. +(** Order *) -Theorem NZlt_irrefl : forall n : Z, ~ (n < n). +Lemma lt_eq_cases : forall n m, n<=m <-> n<m \/ n==m. Proof. -intros n; unfold Zlt, Zeq; simpl. apply lt_irrefl. +intros; apply N.lt_eq_cases. Qed. -Theorem NZlt_succ_r : forall n m : Z, n < (Zsucc m) <-> n <= m. +Theorem lt_irrefl : forall n, ~ (n < n). Proof. -intros n m; unfold Zlt, Zle, Zeq; simpl. rewrite add_succ_l; apply lt_succ_r. +intros; apply N.lt_irrefl. Qed. -Theorem NZmin_l : forall n m : Z, n <= m -> Zmin n m == n. +Theorem lt_succ_r : forall n m, n < (Z.succ m) <-> n <= m. Proof. -unfold Zmin, Zle, Zeq; simpl; intros n m H. -rewrite min_l by assumption. ring. +intros n m; unfold Z.lt, Z.le, Z.eq; simpl; nzsimpl. apply lt_succ_r. Qed. -Theorem NZmin_r : forall n m : Z, m <= n -> Zmin n m == m. +Theorem min_l : forall n m, n <= m -> Z.min n m == n. Proof. -unfold Zmin, Zle, Zeq; simpl; intros n m H. -rewrite min_r by assumption. ring. +unfold Z.min, Z.le, Z.eq; simpl; intros (n1,n2) (m1,m2) H; simpl in *. +rewrite min_l by assumption. +now rewrite <- add_assoc, (add_comm m2). Qed. -Theorem NZmax_l : forall n m : Z, m <= n -> Zmax n m == n. +Theorem min_r : forall n m, m <= n -> Z.min n m == m. Proof. -unfold Zmax, Zle, Zeq; simpl; intros n m H. -rewrite max_l by assumption. ring. +unfold Z.min, Z.le, Z.eq; simpl; intros (n1,n2) (m1,m2) H; simpl in *. +rewrite min_r by assumption. +now rewrite add_assoc. Qed. -Theorem NZmax_r : forall n m : Z, n <= m -> Zmax n m == m. +Theorem max_l : forall n m, m <= n -> Z.max n m == n. Proof. -unfold Zmax, Zle, Zeq; simpl; intros n m H. -rewrite max_r by assumption. ring. +unfold Z.max, Z.le, Z.eq; simpl; intros (n1,n2) (m1,m2) H; simpl in *. +rewrite max_l by assumption. +now rewrite <- add_assoc, (add_comm m2). Qed. -End NZOrdAxiomsMod. - -Definition Zopp (n : Z) : Z := (snd n, fst n). - -Notation "- x" := (Zopp x) : IntScope. - -Instance Zopp_wd : Proper (Zeq ==> Zeq) Zopp. +Theorem max_r : forall n m, n <= m -> Z.max n m == m. Proof. -unfold Zeq; intros n m H; simpl. symmetry. -stepl (fst n + snd m) by apply add_comm. -now stepr (fst m + snd n) by apply add_comm. +unfold Z.max, Z.le, Z.eq; simpl; intros n m H. +rewrite max_r by assumption. +now rewrite add_assoc. Qed. -Open Local Scope IntScope. - -Theorem Zsucc_pred : forall n : Z, Zsucc (Zpred n) == n. +Theorem lt_nge : forall n m, n < m <-> ~(m<=n). Proof. -intro n; unfold Zsucc, Zpred, Zeq; simpl. -rewrite add_succ_l; now rewrite add_succ_r. +intros. apply lt_nge. Qed. -Theorem Zopp_0 : - 0 == 0. +Instance lt_wd : Proper (Z.eq ==> Z.eq ==> iff) Z.lt. Proof. -unfold Zopp, Zeq; simpl. now rewrite add_0_l. +assert (forall n, Proper (Z.eq==>iff) (Z.lt n)). + intros (n1,n2). apply proper_sym_impl_iff; auto with *. + unfold Z.lt, Z.eq; intros (r1,r2) (s1,s2) Eq H; simpl in *. + apply le_lt_add_lt with (r1+r2)%Num (r1+r2)%Num; [apply le_refl; auto with *|]. + rewrite add_shuffle2, (add_comm s2), Eq. + rewrite (add_comm s1 n2), (add_shuffle1 n2), (add_comm n2 r1). + now rewrite <- add_lt_mono_r. +intros n n' Hn m m' Hm. +rewrite Hm. rewrite 2 lt_nge, 2 lt_eq_cases, Hn; auto with *. Qed. -Theorem Zopp_succ : forall n, - (Zsucc n) == Zpred (- n). -Proof. -reflexivity. -Qed. +Definition t := Z.t. +Definition eq := Z.eq. +Definition zero := Z.zero. +Definition succ := Z.succ. +Definition pred := Z.pred. +Definition add := Z.add. +Definition sub := Z.sub. +Definition mul := Z.mul. +Definition opp := Z.opp. +Definition lt := Z.lt. +Definition le := Z.le. +Definition min := Z.min. +Definition max := Z.max. End ZPairsAxiomsMod. @@ -403,9 +311,7 @@ and get their properties *) Require Import NPeano. Module Export ZPairsPeanoAxiomsMod := ZPairsAxiomsMod NPeanoAxiomsMod. -Module Export ZPairsMulOrderPropMod := ZMulOrderPropFunct ZPairsPeanoAxiomsMod. - -Open Local Scope IntScope. +Module Export ZPairsPropMod := ZPropFunct ZPairsPeanoAxiomsMod. Eval compute in (3, 5) * (4, 6). *) diff --git a/theories/Numbers/Integer/SpecViaZ/ZSigZAxioms.v b/theories/Numbers/Integer/SpecViaZ/ZSigZAxioms.v index 823ef149c..e2be10ad9 100644 --- a/theories/Numbers/Integer/SpecViaZ/ZSigZAxioms.v +++ b/theories/Numbers/Integer/SpecViaZ/ZSigZAxioms.v @@ -16,47 +16,37 @@ Require Import ZSig. Module ZSig_ZAxioms (Z:ZType) <: ZAxiomsSig. -Delimit Scope IntScope with Int. -Bind Scope IntScope with Z.t. -Open Local Scope IntScope. -Notation "[ x ]" := (Z.to_Z x) : IntScope. -Infix "==" := Z.eq (at level 70) : IntScope. -Notation "0" := Z.zero : IntScope. -Infix "+" := Z.add : IntScope. -Infix "-" := Z.sub : IntScope. -Infix "*" := Z.mul : IntScope. -Notation "- x" := (Z.opp x) : IntScope. +Delimit Scope NumScope with Num. +Bind Scope NumScope with Z.t. +Local Open Scope NumScope. +Notation "[ x ]" := (Z.to_Z x) : NumScope. +Infix "==" := Z.eq (at level 70) : NumScope. +Notation "0" := Z.zero : NumScope. +Infix "+" := Z.add : NumScope. +Infix "-" := Z.sub : NumScope. +Infix "*" := Z.mul : NumScope. +Notation "- x" := (Z.opp x) : NumScope. +Infix "<=" := Z.le : NumScope. +Infix "<" := Z.lt : NumScope. Hint Rewrite Z.spec_0 Z.spec_1 Z.spec_add Z.spec_sub Z.spec_pred Z.spec_succ - Z.spec_mul Z.spec_opp Z.spec_of_Z : Zspec. + Z.spec_mul Z.spec_opp Z.spec_of_Z : zspec. -Ltac zsimpl := unfold Z.eq in *; autorewrite with Zspec. +Ltac zsimpl := unfold Z.eq in *; autorewrite with zspec. Ltac zcongruence := repeat red; intros; zsimpl; congruence. -Module Export NZOrdAxiomsMod <: NZOrdAxiomsSig. -Module Export NZAxiomsMod <: NZAxiomsSig. - -Definition NZ := Z.t. -Definition NZeq := Z.eq. -Definition NZ0 := Z.zero. -Definition NZsucc := Z.succ. -Definition NZpred := Z.pred. -Definition NZadd := Z.add. -Definition NZsub := Z.sub. -Definition NZmul := Z.mul. - -Instance NZeq_equiv : Equivalence Z.eq. +Instance eq_equiv : Equivalence Z.eq. Obligation Tactic := zcongruence. -Program Instance NZsucc_wd : Proper (Z.eq ==> Z.eq) NZsucc. -Program Instance NZpred_wd : Proper (Z.eq ==> Z.eq) NZpred. -Program Instance NZadd_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) NZadd. -Program Instance NZsub_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) NZsub. -Program Instance NZmul_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) NZmul. +Program Instance succ_wd : Proper (Z.eq ==> Z.eq) Z.succ. +Program Instance pred_wd : Proper (Z.eq ==> Z.eq) Z.pred. +Program Instance add_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.add. +Program Instance sub_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.sub. +Program Instance mul_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.mul. -Theorem NZpred_succ : forall n, Z.pred (Z.succ n) == n. +Theorem pred_succ : forall n, Z.pred (Z.succ n) == n. Proof. intros; zsimpl; auto with zarith. Qed. @@ -107,7 +97,7 @@ intros; rewrite Zopp_succ; unfold Zpred; apply BP; auto. subst z'; auto with zarith. Qed. -Theorem NZinduction : forall n, A n. +Theorem bi_induction : forall n, A n. Proof. intro n. setoid_replace n with (Z.of_Z (Z.to_Z n)). apply B_holds. @@ -116,45 +106,37 @@ Qed. End Induction. -Theorem NZadd_0_l : forall n, 0 + n == n. +Theorem add_0_l : forall n, 0 + n == n. Proof. intros; zsimpl; auto with zarith. Qed. -Theorem NZadd_succ_l : forall n m, (Z.succ n) + m == Z.succ (n + m). +Theorem add_succ_l : forall n m, (Z.succ n) + m == Z.succ (n + m). Proof. intros; zsimpl; auto with zarith. Qed. -Theorem NZsub_0_r : forall n, n - 0 == n. +Theorem sub_0_r : forall n, n - 0 == n. Proof. intros; zsimpl; auto with zarith. Qed. -Theorem NZsub_succ_r : forall n m, n - (Z.succ m) == Z.pred (n - m). +Theorem sub_succ_r : forall n m, n - (Z.succ m) == Z.pred (n - m). Proof. intros; zsimpl; auto with zarith. Qed. -Theorem NZmul_0_l : forall n, 0 * n == 0. +Theorem mul_0_l : forall n, 0 * n == 0. Proof. intros; zsimpl; auto with zarith. Qed. -Theorem NZmul_succ_l : forall n m, (Z.succ n) * m == n * m + m. +Theorem mul_succ_l : forall n m, (Z.succ n) * m == n * m + m. Proof. intros; zsimpl; ring. Qed. -End NZAxiomsMod. - -Definition NZlt := Z.lt. -Definition NZle := Z.le. -Definition NZmin := Z.min. -Definition NZmax := Z.max. - -Infix "<=" := Z.le : IntScope. -Infix "<" := Z.lt : IntScope. +(** Order *) Lemma spec_compare_alt : forall x y, Z.compare x y = ([x] ?= [y])%Z. Proof. @@ -191,85 +173,84 @@ intros x x' Hx y y' Hy. rewrite 2 spec_compare_alt; unfold Z.eq in *; rewrite Hx, Hy; intuition. Qed. -Instance NZlt_wd : Proper (Z.eq ==> Z.eq ==> iff) Z.lt. +Instance lt_wd : Proper (Z.eq ==> Z.eq ==> iff) Z.lt. Proof. intros x x' Hx y y' Hy; unfold Z.lt; rewrite Hx, Hy; intuition. Qed. -Instance NZle_wd : Proper (Z.eq ==> Z.eq ==> iff) Z.le. -Proof. -intros x x' Hx y y' Hy; unfold Z.le; rewrite Hx, Hy; intuition. -Qed. - -Instance NZmin_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.min. -Proof. -repeat red; intros; rewrite 2 spec_min; congruence. -Qed. - -Instance NZmax_wd : Proper (Z.eq ==> Z.eq ==> Z.eq) Z.max. -Proof. -repeat red; intros; rewrite 2 spec_max; congruence. -Qed. - -Theorem NZlt_eq_cases : forall n m, n <= m <-> n < m \/ n == m. +Theorem lt_eq_cases : forall n m, n <= m <-> n < m \/ n == m. Proof. intros. unfold Z.eq; rewrite spec_lt, spec_le; omega. Qed. -Theorem NZlt_irrefl : forall n, ~ n < n. +Theorem lt_irrefl : forall n, ~ n < n. Proof. intros; rewrite spec_lt; auto with zarith. Qed. -Theorem NZlt_succ_r : forall n m, n < (Z.succ m) <-> n <= m. +Theorem lt_succ_r : forall n m, n < (Z.succ m) <-> n <= m. Proof. intros; rewrite spec_lt, spec_le, Z.spec_succ; omega. Qed. -Theorem NZmin_l : forall n m, n <= m -> Z.min n m == n. +Theorem min_l : forall n m, n <= m -> Z.min n m == n. Proof. intros n m; unfold Z.eq; rewrite spec_le, spec_min. generalize (Zmin_spec [n] [m]); omega. Qed. -Theorem NZmin_r : forall n m, m <= n -> Z.min n m == m. +Theorem min_r : forall n m, m <= n -> Z.min n m == m. Proof. intros n m; unfold Z.eq; rewrite spec_le, spec_min. generalize (Zmin_spec [n] [m]); omega. Qed. -Theorem NZmax_l : forall n m, m <= n -> Z.max n m == n. +Theorem max_l : forall n m, m <= n -> Z.max n m == n. Proof. intros n m; unfold Z.eq; rewrite spec_le, spec_max. generalize (Zmax_spec [n] [m]); omega. Qed. -Theorem NZmax_r : forall n m, n <= m -> Z.max n m == m. +Theorem max_r : forall n m, n <= m -> Z.max n m == m. Proof. intros n m; unfold Z.eq; rewrite spec_le, spec_max. generalize (Zmax_spec [n] [m]); omega. Qed. -End NZOrdAxiomsMod. - -Definition Zopp := Z.opp. +(** Part specific to integers, not natural numbers *) -Program Instance Zopp_wd : Proper (Z.eq ==> Z.eq) Z.opp. +Program Instance opp_wd : Proper (Z.eq ==> Z.eq) Z.opp. -Theorem Zsucc_pred : forall n, Z.succ (Z.pred n) == n. +Theorem succ_pred : forall n, Z.succ (Z.pred n) == n. Proof. red; intros; zsimpl; auto with zarith. Qed. -Theorem Zopp_0 : - 0 == 0. +Theorem opp_0 : - 0 == 0. Proof. red; intros; zsimpl; auto with zarith. Qed. -Theorem Zopp_succ : forall n, - (Z.succ n) == Z.pred (- n). +Theorem opp_succ : forall n, - (Z.succ n) == Z.pred (- n). Proof. intros; zsimpl; auto with zarith. Qed. +(** Aliases *) + +Definition t := Z.t. +Definition eq := Z.eq. +Definition zero := Z.zero. +Definition succ := Z.succ. +Definition pred := Z.pred. +Definition add := Z.add. +Definition sub := Z.sub. +Definition mul := Z.mul. +Definition opp := Z.opp. +Definition lt := Z.lt. +Definition le := Z.le. +Definition min := Z.min. +Definition max := Z.max. + End ZSig_ZAxioms. diff --git a/theories/Numbers/NaryFunctions.v b/theories/Numbers/NaryFunctions.v index a8adf49af..417463eba 100644 --- a/theories/Numbers/NaryFunctions.v +++ b/theories/Numbers/NaryFunctions.v @@ -10,7 +10,7 @@ (*i $Id$ i*) -Open Local Scope type_scope. +Local Open Scope type_scope. Require Import List. diff --git a/theories/Numbers/NatInt/NZAdd.v b/theories/Numbers/NatInt/NZAdd.v index 9c852bf90..f7e6699ab 100644 --- a/theories/Numbers/NatInt/NZAdd.v +++ b/theories/Numbers/NatInt/NZAdd.v @@ -13,78 +13,78 @@ Require Import NZAxioms. Require Import NZBase. -Module NZAddPropFunct (Import NZAxiomsMod : NZAxiomsSig). -Module Export NZBasePropMod := NZBasePropFunct NZAxiomsMod. -Open Local Scope NatIntScope. +Module NZAddPropFunct (Import NZ : NZAxiomsSig). +Include NZBasePropFunct NZ. +Local Open Scope NumScope. -Theorem NZadd_0_r : forall n : NZ, n + 0 == n. +Hint Rewrite + pred_succ add_0_l add_succ_l mul_0_l mul_succ_l sub_0_r sub_succ_r : nz. +Ltac nzsimpl := autorewrite with nz. + +Theorem add_0_r : forall n, n + 0 == n. Proof. -NZinduct n. now rewrite NZadd_0_l. -intro. rewrite NZadd_succ_l. now rewrite NZsucc_inj_wd. +nzinduct n. now nzsimpl. +intro. nzsimpl. now rewrite succ_inj_wd. Qed. -Theorem NZadd_succ_r : forall n m : NZ, n + S m == S (n + m). +Theorem add_succ_r : forall n m, n + S m == S (n + m). Proof. -intros n m; NZinduct n. -now do 2 rewrite NZadd_0_l. -intro. repeat rewrite NZadd_succ_l. now rewrite NZsucc_inj_wd. +intros n m; nzinduct n. now nzsimpl. +intro. nzsimpl. now rewrite succ_inj_wd. Qed. -Theorem NZadd_comm : forall n m : NZ, n + m == m + n. +Hint Rewrite add_0_r add_succ_r : nz. + +Theorem add_comm : forall n m, n + m == m + n. Proof. -intros n m; NZinduct n. -rewrite NZadd_0_l; now rewrite NZadd_0_r. -intros n. rewrite NZadd_succ_l; rewrite NZadd_succ_r. now rewrite NZsucc_inj_wd. +intros n m; nzinduct n. now nzsimpl. +intro. nzsimpl. now rewrite succ_inj_wd. Qed. -Theorem NZadd_1_l : forall n : NZ, 1 + n == S n. +Theorem add_1_l : forall n, 1 + n == S n. Proof. -intro n; rewrite NZadd_succ_l; now rewrite NZadd_0_l. +intro n; now nzsimpl. Qed. -Theorem NZadd_1_r : forall n : NZ, n + 1 == S n. +Theorem add_1_r : forall n, n + 1 == S n. Proof. -intro n; rewrite NZadd_comm; apply NZadd_1_l. +intro n; now nzsimpl. Qed. -Theorem NZadd_assoc : forall n m p : NZ, n + (m + p) == (n + m) + p. +Theorem add_assoc : forall n m p, n + (m + p) == (n + m) + p. Proof. -intros n m p; NZinduct n. -now do 2 rewrite NZadd_0_l. -intro. do 3 rewrite NZadd_succ_l. now rewrite NZsucc_inj_wd. +intros n m p; nzinduct n. now nzsimpl. +intro. nzsimpl. now rewrite succ_inj_wd. Qed. -Theorem NZadd_shuffle1 : forall n m p q : NZ, (n + m) + (p + q) == (n + p) + (m + q). +Theorem add_cancel_l : forall n m p, p + n == p + m <-> n == m. Proof. -intros n m p q. -rewrite <- (NZadd_assoc n m (p + q)). rewrite (NZadd_comm m (p + q)). -rewrite <- (NZadd_assoc p q m). rewrite (NZadd_assoc n p (q + m)). -now rewrite (NZadd_comm q m). +intros n m p; nzinduct p. now nzsimpl. +intro p. nzsimpl. now rewrite succ_inj_wd. Qed. -Theorem NZadd_shuffle2 : forall n m p q : NZ, (n + m) + (p + q) == (n + q) + (m + p). +Theorem add_cancel_r : forall n m p, n + p == m + p <-> n == m. Proof. -intros n m p q. -rewrite <- (NZadd_assoc n m (p + q)). rewrite (NZadd_assoc m p q). -rewrite (NZadd_comm (m + p) q). now rewrite <- (NZadd_assoc n q (m + p)). +intros n m p. rewrite (add_comm n p), (add_comm m p). apply add_cancel_l. Qed. -Theorem NZadd_cancel_l : forall n m p : NZ, p + n == p + m <-> n == m. +Theorem add_shuffle1 : forall n m p q, (n + m) + (p + q) == (n + p) + (m + q). Proof. -intros n m p; NZinduct p. -now do 2 rewrite NZadd_0_l. -intro p. do 2 rewrite NZadd_succ_l. now rewrite NZsucc_inj_wd. +intros n m p q. +rewrite <- (add_assoc n m), <- (add_assoc n p), add_cancel_l. +rewrite 2 add_assoc, add_cancel_r. now apply add_comm. Qed. -Theorem NZadd_cancel_r : forall n m p : NZ, n + p == m + p <-> n == m. +Theorem add_shuffle2 : forall n m p q, (n + m) + (p + q) == (n + q) + (m + p). Proof. -intros n m p. rewrite (NZadd_comm n p); rewrite (NZadd_comm m p). -apply NZadd_cancel_l. +intros n m p q. +rewrite <- (add_assoc n m), <- (add_assoc n q), add_cancel_l. +rewrite add_assoc. now apply add_comm. Qed. -Theorem NZsub_1_r : forall n : NZ, n - 1 == P n. +Theorem sub_1_r : forall n, n - 1 == P n. Proof. -intro n; rewrite NZsub_succ_r; now rewrite NZsub_0_r. +intro n; now nzsimpl. Qed. End NZAddPropFunct. diff --git a/theories/Numbers/NatInt/NZAddOrder.v b/theories/Numbers/NatInt/NZAddOrder.v index d1caa83ee..fcfbfd123 100644 --- a/theories/Numbers/NatInt/NZAddOrder.v +++ b/theories/Numbers/NatInt/NZAddOrder.v @@ -10,156 +10,144 @@ (*i $Id$ i*) -Require Import NZAxioms. -Require Import NZOrder. +Require Import NZAxioms NZOrder. -Module NZAddOrderPropFunct (Import NZOrdAxiomsMod : NZOrdAxiomsSig). -Module Export NZOrderPropMod := NZOrderPropFunct NZOrdAxiomsMod. -Open Local Scope NatIntScope. +Module NZAddOrderPropFunct (Import NZ : NZOrdAxiomsSig). +Include NZOrderPropFunct NZ. +Local Open Scope NumScope. -Theorem NZadd_lt_mono_l : forall n m p : NZ, n < m <-> p + n < p + m. +Theorem add_lt_mono_l : forall n m p, n < m <-> p + n < p + m. Proof. -intros n m p; NZinduct p. -now do 2 rewrite NZadd_0_l. -intro p. do 2 rewrite NZadd_succ_l. now rewrite <- NZsucc_lt_mono. +intros n m p; nzinduct p. now nzsimpl. +intro p. nzsimpl. now rewrite <- succ_lt_mono. Qed. -Theorem NZadd_lt_mono_r : forall n m p : NZ, n < m <-> n + p < m + p. +Theorem add_lt_mono_r : forall n m p, n < m <-> n + p < m + p. Proof. -intros n m p. -rewrite (NZadd_comm n p); rewrite (NZadd_comm m p); apply NZadd_lt_mono_l. +intros n m p. rewrite (add_comm n p), (add_comm m p); apply add_lt_mono_l. Qed. -Theorem NZadd_lt_mono : forall n m p q : NZ, n < m -> p < q -> n + p < m + q. +Theorem add_lt_mono : forall n m p q, n < m -> p < q -> n + p < m + q. Proof. intros n m p q H1 H2. -apply NZlt_trans with (m + p); -[now apply -> NZadd_lt_mono_r | now apply -> NZadd_lt_mono_l]. +apply lt_trans with (m + p); +[now apply -> add_lt_mono_r | now apply -> add_lt_mono_l]. Qed. -Theorem NZadd_le_mono_l : forall n m p : NZ, n <= m <-> p + n <= p + m. +Theorem add_le_mono_l : forall n m p, n <= m <-> p + n <= p + m. Proof. -intros n m p; NZinduct p. -now do 2 rewrite NZadd_0_l. -intro p. do 2 rewrite NZadd_succ_l. now rewrite <- NZsucc_le_mono. +intros n m p; nzinduct p. now nzsimpl. +intro p. nzsimpl. now rewrite <- succ_le_mono. Qed. -Theorem NZadd_le_mono_r : forall n m p : NZ, n <= m <-> n + p <= m + p. +Theorem add_le_mono_r : forall n m p, n <= m <-> n + p <= m + p. Proof. -intros n m p. -rewrite (NZadd_comm n p); rewrite (NZadd_comm m p); apply NZadd_le_mono_l. +intros n m p. rewrite (add_comm n p), (add_comm m p); apply add_le_mono_l. Qed. -Theorem NZadd_le_mono : forall n m p q : NZ, n <= m -> p <= q -> n + p <= m + q. +Theorem add_le_mono : forall n m p q, n <= m -> p <= q -> n + p <= m + q. Proof. intros n m p q H1 H2. -apply NZle_trans with (m + p); -[now apply -> NZadd_le_mono_r | now apply -> NZadd_le_mono_l]. +apply le_trans with (m + p); +[now apply -> add_le_mono_r | now apply -> add_le_mono_l]. Qed. -Theorem NZadd_lt_le_mono : forall n m p q : NZ, n < m -> p <= q -> n + p < m + q. +Theorem add_lt_le_mono : forall n m p q, n < m -> p <= q -> n + p < m + q. Proof. intros n m p q H1 H2. -apply NZlt_le_trans with (m + p); -[now apply -> NZadd_lt_mono_r | now apply -> NZadd_le_mono_l]. +apply lt_le_trans with (m + p); +[now apply -> add_lt_mono_r | now apply -> add_le_mono_l]. Qed. -Theorem NZadd_le_lt_mono : forall n m p q : NZ, n <= m -> p < q -> n + p < m + q. +Theorem add_le_lt_mono : forall n m p q, n <= m -> p < q -> n + p < m + q. Proof. intros n m p q H1 H2. -apply NZle_lt_trans with (m + p); -[now apply -> NZadd_le_mono_r | now apply -> NZadd_lt_mono_l]. +apply le_lt_trans with (m + p); +[now apply -> add_le_mono_r | now apply -> add_lt_mono_l]. Qed. -Theorem NZadd_pos_pos : forall n m : NZ, 0 < n -> 0 < m -> 0 < n + m. +Theorem add_pos_pos : forall n m, 0 < n -> 0 < m -> 0 < n + m. Proof. -intros n m H1 H2. rewrite <- (NZadd_0_l 0). now apply NZadd_lt_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_lt_mono. Qed. -Theorem NZadd_pos_nonneg : forall n m : NZ, 0 < n -> 0 <= m -> 0 < n + m. +Theorem add_pos_nonneg : forall n m, 0 < n -> 0 <= m -> 0 < n + m. Proof. -intros n m H1 H2. rewrite <- (NZadd_0_l 0). now apply NZadd_lt_le_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_lt_le_mono. Qed. -Theorem NZadd_nonneg_pos : forall n m : NZ, 0 <= n -> 0 < m -> 0 < n + m. +Theorem add_nonneg_pos : forall n m, 0 <= n -> 0 < m -> 0 < n + m. Proof. -intros n m H1 H2. rewrite <- (NZadd_0_l 0). now apply NZadd_le_lt_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_le_lt_mono. Qed. -Theorem NZadd_nonneg_nonneg : forall n m : NZ, 0 <= n -> 0 <= m -> 0 <= n + m. +Theorem add_nonneg_nonneg : forall n m, 0 <= n -> 0 <= m -> 0 <= n + m. Proof. -intros n m H1 H2. rewrite <- (NZadd_0_l 0). now apply NZadd_le_mono. +intros n m H1 H2. rewrite <- (add_0_l 0). now apply add_le_mono. Qed. -Theorem NZlt_add_pos_l : forall n m : NZ, 0 < n -> m < n + m. +Theorem lt_add_pos_l : forall n m, 0 < n -> m < n + m. Proof. -intros n m H. apply -> (NZadd_lt_mono_r 0 n m) in H. -now rewrite NZadd_0_l in H. +intros n m. rewrite (add_lt_mono_r 0 n m). now nzsimpl. Qed. -Theorem NZlt_add_pos_r : forall n m : NZ, 0 < n -> m < m + n. +Theorem lt_add_pos_r : forall n m, 0 < n -> m < m + n. Proof. -intros; rewrite NZadd_comm; now apply NZlt_add_pos_l. +intros; rewrite add_comm; now apply lt_add_pos_l. Qed. -Theorem NZle_lt_add_lt : forall n m p q : NZ, n <= m -> p + m < q + n -> p < q. +Theorem le_lt_add_lt : forall n m p q, n <= m -> p + m < q + n -> p < q. Proof. -intros n m p q H1 H2. destruct (NZle_gt_cases q p); [| assumption]. -pose proof (NZadd_le_mono q p n m H H1) as H3. apply <- NZnle_gt in H2. -false_hyp H3 H2. +intros n m p q H1 H2. destruct (le_gt_cases q p); [| assumption]. +contradict H2. rewrite nlt_ge. now apply add_le_mono. Qed. -Theorem NZlt_le_add_lt : forall n m p q : NZ, n < m -> p + m <= q + n -> p < q. +Theorem lt_le_add_lt : forall n m p q, n < m -> p + m <= q + n -> p < q. Proof. -intros n m p q H1 H2. destruct (NZle_gt_cases q p); [| assumption]. -pose proof (NZadd_le_lt_mono q p n m H H1) as H3. apply <- NZnle_gt in H3. -false_hyp H2 H3. +intros n m p q H1 H2. destruct (le_gt_cases q p); [| assumption]. +contradict H2. rewrite nle_gt. now apply add_le_lt_mono. Qed. -Theorem NZle_le_add_le : forall n m p q : NZ, n <= m -> p + m <= q + n -> p <= q. +Theorem le_le_add_le : forall n m p q, n <= m -> p + m <= q + n -> p <= q. Proof. -intros n m p q H1 H2. destruct (NZle_gt_cases p q); [assumption |]. -pose proof (NZadd_lt_le_mono q p n m H H1) as H3. apply <- NZnle_gt in H3. -false_hyp H2 H3. +intros n m p q H1 H2. destruct (le_gt_cases p q); [assumption |]. +contradict H2. rewrite nle_gt. now apply add_lt_le_mono. Qed. -Theorem NZadd_lt_cases : forall n m p q : NZ, n + m < p + q -> n < p \/ m < q. +Theorem add_lt_cases : forall n m p q, n + m < p + q -> n < p \/ m < q. Proof. intros n m p q H; -destruct (NZle_gt_cases p n) as [H1 | H1]. -destruct (NZle_gt_cases q m) as [H2 | H2]. -pose proof (NZadd_le_mono p n q m H1 H2) as H3. apply -> NZle_ngt in H3. -false_hyp H H3. -now right. now left. +destruct (le_gt_cases p n) as [H1 | H1]; [| now left]. +destruct (le_gt_cases q m) as [H2 | H2]; [| now right]. +contradict H; rewrite nlt_ge. now apply add_le_mono. Qed. -Theorem NZadd_le_cases : forall n m p q : NZ, n + m <= p + q -> n <= p \/ m <= q. +Theorem add_le_cases : forall n m p q, n + m <= p + q -> n <= p \/ m <= q. Proof. intros n m p q H. -destruct (NZle_gt_cases n p) as [H1 | H1]. now left. -destruct (NZle_gt_cases m q) as [H2 | H2]. now right. -assert (H3 : p + q < n + m) by now apply NZadd_lt_mono. -apply -> NZle_ngt in H. false_hyp H3 H. +destruct (le_gt_cases n p) as [H1 | H1]. now left. +destruct (le_gt_cases m q) as [H2 | H2]. now right. +contradict H; rewrite nle_gt. now apply add_lt_mono. Qed. -Theorem NZadd_neg_cases : forall n m : NZ, n + m < 0 -> n < 0 \/ m < 0. +Theorem add_neg_cases : forall n m, n + m < 0 -> n < 0 \/ m < 0. Proof. -intros n m H; apply NZadd_lt_cases; now rewrite NZadd_0_l. +intros n m H; apply add_lt_cases; now nzsimpl. Qed. -Theorem NZadd_pos_cases : forall n m : NZ, 0 < n + m -> 0 < n \/ 0 < m. +Theorem add_pos_cases : forall n m, 0 < n + m -> 0 < n \/ 0 < m. Proof. -intros n m H; apply NZadd_lt_cases; now rewrite NZadd_0_l. +intros n m H; apply add_lt_cases; now nzsimpl. Qed. -Theorem NZadd_nonpos_cases : forall n m : NZ, n + m <= 0 -> n <= 0 \/ m <= 0. +Theorem add_nonpos_cases : forall n m, n + m <= 0 -> n <= 0 \/ m <= 0. Proof. -intros n m H; apply NZadd_le_cases; now rewrite NZadd_0_l. +intros n m H; apply add_le_cases; now nzsimpl. Qed. -Theorem NZadd_nonneg_cases : forall n m : NZ, 0 <= n + m -> 0 <= n \/ 0 <= m. +Theorem add_nonneg_cases : forall n m, 0 <= n + m -> 0 <= n \/ 0 <= m. Proof. -intros n m H; apply NZadd_le_cases; now rewrite NZadd_0_l. +intros n m H; apply add_le_cases; now nzsimpl. Qed. End NZAddOrderPropFunct. diff --git a/theories/Numbers/NatInt/NZAxioms.v b/theories/Numbers/NatInt/NZAxioms.v index 8499054b5..9dd6eaf05 100644 --- a/theories/Numbers/NatInt/NZAxioms.v +++ b/theories/Numbers/NatInt/NZAxioms.v @@ -14,80 +14,79 @@ Require Export NumPrelude. Module Type NZAxiomsSig. -Parameter Inline NZ : Type. -Parameter Inline NZeq : NZ -> NZ -> Prop. -Parameter Inline NZ0 : NZ. -Parameter Inline NZsucc : NZ -> NZ. -Parameter Inline NZpred : NZ -> NZ. -Parameter Inline NZadd : NZ -> NZ -> NZ. -Parameter Inline NZsub : NZ -> NZ -> NZ. -Parameter Inline NZmul : NZ -> NZ -> NZ. +Parameter Inline t : Type. +Parameter Inline eq : t -> t -> Prop. +Parameter Inline zero : t. +Parameter Inline succ : t -> t. +Parameter Inline pred : t -> t. +Parameter Inline add : t -> t -> t. +Parameter Inline sub : t -> t -> t. +Parameter Inline mul : t -> t -> t. (* Unary subtraction (opp) is not defined on natural numbers, so we have it for integers only *) -Instance NZeq_equiv : Equivalence NZeq. -Instance NZsucc_wd : Proper (NZeq ==> NZeq) NZsucc. -Instance NZpred_wd : Proper (NZeq ==> NZeq) NZpred. -Instance NZadd_wd : Proper (NZeq ==> NZeq ==> NZeq) NZadd. -Instance NZsub_wd : Proper (NZeq ==> NZeq ==> NZeq) NZsub. -Instance NZmul_wd : Proper (NZeq ==> NZeq ==> NZeq) NZmul. +Instance eq_equiv : Equivalence eq. +Instance succ_wd : Proper (eq ==> eq) succ. +Instance pred_wd : Proper (eq ==> eq) pred. +Instance add_wd : Proper (eq ==> eq ==> eq) add. +Instance sub_wd : Proper (eq ==> eq ==> eq) sub. +Instance mul_wd : Proper (eq ==> eq ==> eq) mul. -Delimit Scope NatIntScope with NatInt. -Open Local Scope NatIntScope. -Notation "x == y" := (NZeq x y) (at level 70) : NatIntScope. -Notation "x ~= y" := (~ NZeq x y) (at level 70) : NatIntScope. -Notation "0" := NZ0 : NatIntScope. -Notation S := NZsucc. -Notation P := NZpred. -Notation "1" := (S 0) : NatIntScope. -Notation "x + y" := (NZadd x y) : NatIntScope. -Notation "x - y" := (NZsub x y) : NatIntScope. -Notation "x * y" := (NZmul x y) : NatIntScope. +Delimit Scope NumScope with Num. +Local Open Scope NumScope. +Notation "x == y" := (eq x y) (at level 70) : NumScope. +Notation "x ~= y" := (~ eq x y) (at level 70) : NumScope. +Notation "0" := zero : NumScope. +Notation S := succ. +Notation P := pred. +Notation "1" := (S 0) : NumScope. +Notation "x + y" := (add x y) : NumScope. +Notation "x - y" := (sub x y) : NumScope. +Notation "x * y" := (mul x y) : NumScope. -Axiom NZpred_succ : forall n : NZ, P (S n) == n. +Axiom pred_succ : forall n, P (S n) == n. -Axiom NZinduction : - forall A : NZ -> Prop, Proper (NZeq==>iff) A -> - A 0 -> (forall n : NZ, A n <-> A (S n)) -> forall n : NZ, A n. +Axiom bi_induction : + forall A : t -> Prop, Proper (eq==>iff) A -> + A 0 -> (forall n, A n <-> A (S n)) -> forall n, A n. -Axiom NZadd_0_l : forall n : NZ, 0 + n == n. -Axiom NZadd_succ_l : forall n m : NZ, (S n) + m == S (n + m). +Axiom add_0_l : forall n, 0 + n == n. +Axiom add_succ_l : forall n m, (S n) + m == S (n + m). -Axiom NZsub_0_r : forall n : NZ, n - 0 == n. -Axiom NZsub_succ_r : forall n m : NZ, n - (S m) == P (n - m). +Axiom sub_0_r : forall n, n - 0 == n. +Axiom sub_succ_r : forall n m, n - (S m) == P (n - m). -Axiom NZmul_0_l : forall n : NZ, 0 * n == 0. -Axiom NZmul_succ_l : forall n m : NZ, S n * m == n * m + m. +Axiom mul_0_l : forall n, 0 * n == 0. +Axiom mul_succ_l : forall n m, S n * m == n * m + m. End NZAxiomsSig. Module Type NZOrdAxiomsSig. -Declare Module Export NZAxiomsMod : NZAxiomsSig. -Open Local Scope NatIntScope. - -Parameter Inline NZlt : NZ -> NZ -> Prop. -Parameter Inline NZle : NZ -> NZ -> Prop. -Parameter Inline NZmin : NZ -> NZ -> NZ. -Parameter Inline NZmax : NZ -> NZ -> NZ. - -Instance NZlt_wd : Proper (NZeq ==> NZeq ==> iff) NZlt. -Instance NZle_wd : Proper (NZeq ==> NZeq ==> iff) NZle. -Instance NZmin_wd : Proper (NZeq ==> NZeq ==> NZeq) NZmin. -Instance NZmax_wd : Proper (NZeq ==> NZeq ==> NZeq) NZmax. - -Notation "x < y" := (NZlt x y) : NatIntScope. -Notation "x <= y" := (NZle x y) : NatIntScope. -Notation "x > y" := (NZlt y x) (only parsing) : NatIntScope. -Notation "x >= y" := (NZle y x) (only parsing) : NatIntScope. - -Axiom NZlt_eq_cases : forall n m : NZ, n <= m <-> n < m \/ n == m. -Axiom NZlt_irrefl : forall n : NZ, ~ (n < n). -Axiom NZlt_succ_r : forall n m : NZ, n < S m <-> n <= m. - -Axiom NZmin_l : forall n m : NZ, n <= m -> NZmin n m == n. -Axiom NZmin_r : forall n m : NZ, m <= n -> NZmin n m == m. -Axiom NZmax_l : forall n m : NZ, m <= n -> NZmax n m == n. -Axiom NZmax_r : forall n m : NZ, n <= m -> NZmax n m == m. +Include Type NZAxiomsSig. +Local Open Scope NumScope. + +Parameter Inline lt : t -> t -> Prop. +Parameter Inline le : t -> t -> Prop. + +Notation "x < y" := (lt x y) : NumScope. +Notation "x <= y" := (le x y) : NumScope. +Notation "x > y" := (lt y x) (only parsing) : NumScope. +Notation "x >= y" := (le y x) (only parsing) : NumScope. + +Instance lt_wd : Proper (eq ==> eq ==> iff) lt. +(** Compatibility of [le] can be proved later from [lt_wd] and [lt_eq_cases] *) + +Axiom lt_eq_cases : forall n m, n <= m <-> n < m \/ n == m. +Axiom lt_irrefl : forall n, ~ (n < n). +Axiom lt_succ_r : forall n m, n < S m <-> n <= m. + +Parameter Inline min : t -> t -> t. +Parameter Inline max : t -> t -> t. +(** Compatibility of [min] and [max] can be proved later *) +Axiom min_l : forall n m, n <= m -> min n m == n. +Axiom min_r : forall n m, m <= n -> min n m == m. +Axiom max_l : forall n m, m <= n -> max n m == n. +Axiom max_r : forall n m, n <= m -> max n m == m. End NZOrdAxiomsSig. diff --git a/theories/Numbers/NatInt/NZBase.v b/theories/Numbers/NatInt/NZBase.v index 0c9d006d6..b95824565 100644 --- a/theories/Numbers/NatInt/NZBase.v +++ b/theories/Numbers/NatInt/NZBase.v @@ -12,41 +12,48 @@ Require Import NZAxioms. -Module NZBasePropFunct (Import NZAxiomsMod : NZAxiomsSig). -Open Local Scope NatIntScope. +Module NZBasePropFunct (Import NZ : NZAxiomsSig). +Local Open Scope NumScope. -Theorem NZneq_sym : forall n m : NZ, n ~= m -> m ~= n. +Definition eq_refl := @Equivalence_Reflexive _ _ eq_equiv. +Definition eq_sym := @Equivalence_Symmetric _ _ eq_equiv. +Definition eq_trans := @Equivalence_Transitive _ _ eq_equiv. + +(* TODO: how register ~= (which is just a notation) as a Symmetric relation, + hence allowing "symmetry" tac ? *) + +Theorem neq_sym : forall n m, n ~= m -> m ~= n. Proof. intros n m H1 H2; symmetry in H2; false_hyp H2 H1. Qed. -Theorem NZE_stepl : forall x y z : NZ, x == y -> x == z -> z == y. +Theorem eq_stepl : forall x y z, x == y -> x == z -> z == y. Proof. intros x y z H1 H2; now rewrite <- H1. Qed. -Declare Left Step NZE_stepl. -(* The right step lemma is just the transitivity of NZeq *) -Declare Right Step (@Equivalence_Transitive _ _ NZeq_equiv). +Declare Left Step eq_stepl. +(* The right step lemma is just the transitivity of eq *) +Declare Right Step (@Equivalence_Transitive _ _ eq_equiv). -Theorem NZsucc_inj : forall n1 n2 : NZ, S n1 == S n2 -> n1 == n2. +Theorem succ_inj : forall n1 n2, S n1 == S n2 -> n1 == n2. Proof. intros n1 n2 H. -apply NZpred_wd in H. now do 2 rewrite NZpred_succ in H. +apply pred_wd in H. now do 2 rewrite pred_succ in H. Qed. (* The following theorem is useful as an equivalence for proving bidirectional induction steps *) -Theorem NZsucc_inj_wd : forall n1 n2 : NZ, S n1 == S n2 <-> n1 == n2. +Theorem succ_inj_wd : forall n1 n2, S n1 == S n2 <-> n1 == n2. Proof. intros; split. -apply NZsucc_inj. -apply NZsucc_wd. +apply succ_inj. +apply succ_wd. Qed. -Theorem NZsucc_inj_wd_neg : forall n m : NZ, S n ~= S m <-> n ~= m. +Theorem succ_inj_wd_neg : forall n m, S n ~= S m <-> n ~= m. Proof. -intros; now rewrite NZsucc_inj_wd. +intros; now rewrite succ_inj_wd. Qed. (* We cannot prove that the predecessor is injective, nor that it is @@ -54,28 +61,27 @@ left-inverse to the successor at this point *) Section CentralInduction. -Variable A : predicate NZ. - -Hypothesis A_wd : Proper (NZeq==>iff) A. +Variable A : predicate t. +Hypothesis A_wd : Proper (eq==>iff) A. -Theorem NZcentral_induction : - forall z : NZ, A z -> - (forall n : NZ, A n <-> A (S n)) -> - forall n : NZ, A n. +Theorem central_induction : + forall z, A z -> + (forall n, A n <-> A (S n)) -> + forall n, A n. Proof. -intros z Base Step; revert Base; pattern z; apply NZinduction. +intros z Base Step; revert Base; pattern z; apply bi_induction. solve_predicate_wd. -intro; now apply NZinduction. +intro; now apply bi_induction. intro; pose proof (Step n); tauto. Qed. End CentralInduction. -Tactic Notation "NZinduct" ident(n) := - induction_maker n ltac:(apply NZinduction). +Tactic Notation "nzinduct" ident(n) := + induction_maker n ltac:(apply bi_induction). -Tactic Notation "NZinduct" ident(n) constr(u) := - induction_maker n ltac:(apply NZcentral_induction with (z := u)). +Tactic Notation "nzinduct" ident(n) constr(u) := + induction_maker n ltac:(apply central_induction with (z := u)). End NZBasePropFunct. diff --git a/theories/Numbers/NatInt/NZMul.v b/theories/Numbers/NatInt/NZMul.v index 7d9b1aabd..c76e25c64 100644 --- a/theories/Numbers/NatInt/NZMul.v +++ b/theories/Numbers/NatInt/NZMul.v @@ -13,67 +13,59 @@ Require Import NZAxioms. Require Import NZAdd. -Module NZMulPropFunct (Import NZAxiomsMod : NZAxiomsSig). -Module Export NZAddPropMod := NZAddPropFunct NZAxiomsMod. -Open Local Scope NatIntScope. +Module NZMulPropFunct (Import NZ : NZAxiomsSig). +Include NZAddPropFunct NZ. +Local Open Scope NumScope. -Theorem NZmul_0_r : forall n : NZ, n * 0 == 0. +Theorem mul_0_r : forall n, n * 0 == 0. Proof. -NZinduct n. -now rewrite NZmul_0_l. -intro. rewrite NZmul_succ_l. now rewrite NZadd_0_r. +nzinduct n; intros; now nzsimpl. Qed. -Theorem NZmul_succ_r : forall n m : NZ, n * (S m) == n * m + n. +Theorem mul_succ_r : forall n m, n * (S m) == n * m + n. Proof. -intros n m; NZinduct n. -do 2 rewrite NZmul_0_l; now rewrite NZadd_0_l. -intro n. do 2 rewrite NZmul_succ_l. do 2 rewrite NZadd_succ_r. -rewrite NZsucc_inj_wd. rewrite <- (NZadd_assoc (n * m) m n). -rewrite (NZadd_comm m n). rewrite NZadd_assoc. -now rewrite NZadd_cancel_r. +intros n m; nzinduct n. now nzsimpl. +intro n. nzsimpl. rewrite succ_inj_wd, <- add_assoc, (add_comm m n), add_assoc. +now rewrite add_cancel_r. Qed. -Theorem NZmul_comm : forall n m : NZ, n * m == m * n. +Hint Rewrite mul_0_r mul_succ_r : nz. + +Theorem mul_comm : forall n m, n * m == m * n. Proof. -intros n m; NZinduct n. -rewrite NZmul_0_l; now rewrite NZmul_0_r. -intro. rewrite NZmul_succ_l; rewrite NZmul_succ_r. now rewrite NZadd_cancel_r. +intros n m; nzinduct n. now nzsimpl. +intro. nzsimpl. now rewrite add_cancel_r. Qed. -Theorem NZmul_add_distr_r : forall n m p : NZ, (n + m) * p == n * p + m * p. +Theorem mul_add_distr_r : forall n m p, (n + m) * p == n * p + m * p. Proof. -intros n m p; NZinduct n. -rewrite NZmul_0_l. now do 2 rewrite NZadd_0_l. -intro n. rewrite NZadd_succ_l. do 2 rewrite NZmul_succ_l. -rewrite <- (NZadd_assoc (n * p) p (m * p)). -rewrite (NZadd_comm p (m * p)). rewrite (NZadd_assoc (n * p) (m * p) p). -now rewrite NZadd_cancel_r. +intros n m p; nzinduct n. now nzsimpl. +intro n. nzsimpl. rewrite <- add_assoc, (add_comm p (m*p)), add_assoc. +now rewrite add_cancel_r. Qed. -Theorem NZmul_add_distr_l : forall n m p : NZ, n * (m + p) == n * m + n * p. +Theorem mul_add_distr_l : forall n m p, n * (m + p) == n * m + n * p. Proof. intros n m p. -rewrite (NZmul_comm n (m + p)). rewrite (NZmul_comm n m). -rewrite (NZmul_comm n p). apply NZmul_add_distr_r. +rewrite (mul_comm n (m + p)), (mul_comm n m), (mul_comm n p). +apply mul_add_distr_r. Qed. -Theorem NZmul_assoc : forall n m p : NZ, n * (m * p) == (n * m) * p. +Theorem mul_assoc : forall n m p, n * (m * p) == (n * m) * p. Proof. -intros n m p; NZinduct n. -now do 3 rewrite NZmul_0_l. -intro n. do 2 rewrite NZmul_succ_l. rewrite NZmul_add_distr_r. -now rewrite NZadd_cancel_r. +intros n m p; nzinduct n. now nzsimpl. +intro n. nzsimpl. rewrite mul_add_distr_r. +now rewrite add_cancel_r. Qed. -Theorem NZmul_1_l : forall n : NZ, 1 * n == n. +Theorem mul_1_l : forall n, 1 * n == n. Proof. -intro n. rewrite NZmul_succ_l; rewrite NZmul_0_l. now rewrite NZadd_0_l. +intro n. now nzsimpl. Qed. -Theorem NZmul_1_r : forall n : NZ, n * 1 == n. +Theorem mul_1_r : forall n, n * 1 == n. Proof. -intro n; rewrite NZmul_comm; apply NZmul_1_l. +intro n. now nzsimpl. Qed. End NZMulPropFunct. diff --git a/theories/Numbers/NatInt/NZMulOrder.v b/theories/Numbers/NatInt/NZMulOrder.v index d6eea61c8..306b69022 100644 --- a/theories/Numbers/NatInt/NZMulOrder.v +++ b/theories/Numbers/NatInt/NZMulOrder.v @@ -13,298 +13,291 @@ Require Import NZAxioms. Require Import NZAddOrder. -Module NZMulOrderPropFunct (Import NZOrdAxiomsMod : NZOrdAxiomsSig). -Module Export NZAddOrderPropMod := NZAddOrderPropFunct NZOrdAxiomsMod. -Open Local Scope NatIntScope. +Module NZMulOrderPropFunct (Import NZ : NZOrdAxiomsSig). +Include NZAddOrderPropFunct NZ. +Local Open Scope NumScope. -Theorem NZmul_lt_pred : - forall p q n m : NZ, S p == q -> (p * n < p * m <-> q * n + m < q * m + n). +Theorem mul_lt_pred : + forall p q n m, S p == q -> (p * n < p * m <-> q * n + m < q * m + n). Proof. -intros p q n m H. rewrite <- H. do 2 rewrite NZmul_succ_l. -rewrite <- (NZadd_assoc (p * n) n m). -rewrite <- (NZadd_assoc (p * m) m n). -rewrite (NZadd_comm n m). now rewrite <- NZadd_lt_mono_r. +intros p q n m H. rewrite <- H. nzsimpl. +rewrite <- ! add_assoc, (add_comm n m). +now rewrite <- add_lt_mono_r. Qed. -Theorem NZmul_lt_mono_pos_l : forall p n m : NZ, 0 < p -> (n < m <-> p * n < p * m). +Theorem mul_lt_mono_pos_l : forall p n m, 0 < p -> (n < m <-> p * n < p * m). Proof. -NZord_induct p. -intros n m H; false_hyp H NZlt_irrefl. -intros p H IH n m H1. do 2 rewrite NZmul_succ_l. -le_elim H. assert (LR : forall n m : NZ, n < m -> p * n + n < p * m + m). -intros n1 m1 H2. apply NZadd_lt_mono; [now apply -> IH | assumption]. -split; [apply LR |]. intro H2. apply -> NZlt_dne; intro H3. -apply <- NZle_ngt in H3. le_elim H3. -apply NZlt_asymm in H2. apply H2. now apply LR. -rewrite H3 in H2; false_hyp H2 NZlt_irrefl. -rewrite <- H; do 2 rewrite NZmul_0_l; now do 2 rewrite NZadd_0_l. -intros p H1 _ n m H2. apply NZlt_asymm in H1. false_hyp H2 H1. +nzord_induct p. +intros n m H; false_hyp H lt_irrefl. +intros p H IH n m H1. nzsimpl. +le_elim H. assert (LR : forall n m, n < m -> p * n + n < p * m + m). +intros n1 m1 H2. apply add_lt_mono; [now apply -> IH | assumption]. +split; [apply LR |]. intro H2. apply -> lt_dne; intro H3. +apply <- le_ngt in H3. le_elim H3. +apply lt_asymm in H2. apply H2. now apply LR. +rewrite H3 in H2; false_hyp H2 lt_irrefl. +rewrite <- H; now nzsimpl. +intros p H1 _ n m H2. destruct (lt_asymm _ _ H1 H2). Qed. -Theorem NZmul_lt_mono_pos_r : forall p n m : NZ, 0 < p -> (n < m <-> n * p < m * p). +Theorem mul_lt_mono_pos_r : forall p n m, 0 < p -> (n < m <-> n * p < m * p). Proof. intros p n m. -rewrite (NZmul_comm n p); rewrite (NZmul_comm m p). now apply NZmul_lt_mono_pos_l. +rewrite (mul_comm n p), (mul_comm m p). now apply mul_lt_mono_pos_l. Qed. -Theorem NZmul_lt_mono_neg_l : forall p n m : NZ, p < 0 -> (n < m <-> p * m < p * n). +Theorem mul_lt_mono_neg_l : forall p n m, p < 0 -> (n < m <-> p * m < p * n). Proof. -NZord_induct p. -intros n m H; false_hyp H NZlt_irrefl. -intros p H1 _ n m H2. apply NZlt_succ_l in H2. apply <- NZnle_gt in H2. false_hyp H1 H2. -intros p H IH n m H1. apply <- NZle_succ_l in H. -le_elim H. assert (LR : forall n m : NZ, n < m -> p * m < p * n). -intros n1 m1 H2. apply (NZle_lt_add_lt n1 m1). -now apply NZlt_le_incl. do 2 rewrite <- NZmul_succ_l. now apply -> IH. -split; [apply LR |]. intro H2. apply -> NZlt_dne; intro H3. -apply <- NZle_ngt in H3. le_elim H3. -apply NZlt_asymm in H2. apply H2. now apply LR. -rewrite H3 in H2; false_hyp H2 NZlt_irrefl. -rewrite (NZmul_lt_pred p (S p)) by reflexivity. -rewrite H; do 2 rewrite NZmul_0_l; now do 2 rewrite NZadd_0_l. +nzord_induct p. +intros n m H; false_hyp H lt_irrefl. +intros p H1 _ n m H2. apply lt_succ_l in H2. apply <- nle_gt in H2. +false_hyp H1 H2. +intros p H IH n m H1. apply <- le_succ_l in H. +le_elim H. assert (LR : forall n m, n < m -> p * m < p * n). +intros n1 m1 H2. apply (le_lt_add_lt n1 m1). +now apply lt_le_incl. rewrite <- 2 mul_succ_l. now apply -> IH. +split; [apply LR |]. intro H2. apply -> lt_dne; intro H3. +apply <- le_ngt in H3. le_elim H3. +apply lt_asymm in H2. apply H2. now apply LR. +rewrite H3 in H2; false_hyp H2 lt_irrefl. +rewrite (mul_lt_pred p (S p)) by reflexivity. +rewrite H; do 2 rewrite mul_0_l; now do 2 rewrite add_0_l. Qed. -Theorem NZmul_lt_mono_neg_r : forall p n m : NZ, p < 0 -> (n < m <-> m * p < n * p). +Theorem mul_lt_mono_neg_r : forall p n m, p < 0 -> (n < m <-> m * p < n * p). Proof. intros p n m. -rewrite (NZmul_comm n p); rewrite (NZmul_comm m p). now apply NZmul_lt_mono_neg_l. +rewrite (mul_comm n p), (mul_comm m p). now apply mul_lt_mono_neg_l. Qed. -Theorem NZmul_le_mono_nonneg_l : forall n m p : NZ, 0 <= p -> n <= m -> p * n <= p * m. +Theorem mul_le_mono_nonneg_l : forall n m p, 0 <= p -> n <= m -> p * n <= p * m. Proof. intros n m p H1 H2. le_elim H1. -le_elim H2. apply NZlt_le_incl. now apply -> NZmul_lt_mono_pos_l. -apply NZeq_le_incl; now rewrite H2. -apply NZeq_le_incl; rewrite <- H1; now do 2 rewrite NZmul_0_l. +le_elim H2. apply lt_le_incl. now apply -> mul_lt_mono_pos_l. +apply eq_le_incl; now rewrite H2. +apply eq_le_incl; rewrite <- H1; now do 2 rewrite mul_0_l. Qed. -Theorem NZmul_le_mono_nonpos_l : forall n m p : NZ, p <= 0 -> n <= m -> p * m <= p * n. +Theorem mul_le_mono_nonpos_l : forall n m p, p <= 0 -> n <= m -> p * m <= p * n. Proof. intros n m p H1 H2. le_elim H1. -le_elim H2. apply NZlt_le_incl. now apply -> NZmul_lt_mono_neg_l. -apply NZeq_le_incl; now rewrite H2. -apply NZeq_le_incl; rewrite H1; now do 2 rewrite NZmul_0_l. +le_elim H2. apply lt_le_incl. now apply -> mul_lt_mono_neg_l. +apply eq_le_incl; now rewrite H2. +apply eq_le_incl; rewrite H1; now do 2 rewrite mul_0_l. Qed. -Theorem NZmul_le_mono_nonneg_r : forall n m p : NZ, 0 <= p -> n <= m -> n * p <= m * p. +Theorem mul_le_mono_nonneg_r : forall n m p, 0 <= p -> n <= m -> n * p <= m * p. Proof. -intros n m p H1 H2; rewrite (NZmul_comm n p); rewrite (NZmul_comm m p); -now apply NZmul_le_mono_nonneg_l. +intros n m p H1 H2; +rewrite (mul_comm n p), (mul_comm m p); now apply mul_le_mono_nonneg_l. Qed. -Theorem NZmul_le_mono_nonpos_r : forall n m p : NZ, p <= 0 -> n <= m -> m * p <= n * p. +Theorem mul_le_mono_nonpos_r : forall n m p, p <= 0 -> n <= m -> m * p <= n * p. Proof. -intros n m p H1 H2; rewrite (NZmul_comm n p); rewrite (NZmul_comm m p); -now apply NZmul_le_mono_nonpos_l. +intros n m p H1 H2; +rewrite (mul_comm n p), (mul_comm m p); now apply mul_le_mono_nonpos_l. Qed. -Theorem NZmul_cancel_l : forall n m p : NZ, p ~= 0 -> (p * n == p * m <-> n == m). +Theorem mul_cancel_l : forall n m p, p ~= 0 -> (p * n == p * m <-> n == m). Proof. intros n m p H; split; intro H1. -destruct (NZlt_trichotomy p 0) as [H2 | [H2 | H2]]. -apply -> NZeq_dne; intro H3. apply -> NZlt_gt_cases in H3. destruct H3 as [H3 | H3]. -assert (H4 : p * m < p * n); [now apply -> NZmul_lt_mono_neg_l |]. -rewrite H1 in H4; false_hyp H4 NZlt_irrefl. -assert (H4 : p * n < p * m); [now apply -> NZmul_lt_mono_neg_l |]. -rewrite H1 in H4; false_hyp H4 NZlt_irrefl. +destruct (lt_trichotomy p 0) as [H2 | [H2 | H2]]. +apply -> eq_dne; intro H3. apply -> lt_gt_cases in H3. destruct H3 as [H3 | H3]. +assert (H4 : p * m < p * n); [now apply -> mul_lt_mono_neg_l |]. +rewrite H1 in H4; false_hyp H4 lt_irrefl. +assert (H4 : p * n < p * m); [now apply -> mul_lt_mono_neg_l |]. +rewrite H1 in H4; false_hyp H4 lt_irrefl. false_hyp H2 H. -apply -> NZeq_dne; intro H3. apply -> NZlt_gt_cases in H3. destruct H3 as [H3 | H3]. -assert (H4 : p * n < p * m) by (now apply -> NZmul_lt_mono_pos_l). -rewrite H1 in H4; false_hyp H4 NZlt_irrefl. -assert (H4 : p * m < p * n) by (now apply -> NZmul_lt_mono_pos_l). -rewrite H1 in H4; false_hyp H4 NZlt_irrefl. +apply -> eq_dne; intro H3. apply -> lt_gt_cases in H3. destruct H3 as [H3 | H3]. +assert (H4 : p * n < p * m) by (now apply -> mul_lt_mono_pos_l). +rewrite H1 in H4; false_hyp H4 lt_irrefl. +assert (H4 : p * m < p * n) by (now apply -> mul_lt_mono_pos_l). +rewrite H1 in H4; false_hyp H4 lt_irrefl. now rewrite H1. Qed. -Theorem NZmul_cancel_r : forall n m p : NZ, p ~= 0 -> (n * p == m * p <-> n == m). +Theorem mul_cancel_r : forall n m p, p ~= 0 -> (n * p == m * p <-> n == m). Proof. -intros n m p. rewrite (NZmul_comm n p), (NZmul_comm m p); apply NZmul_cancel_l. +intros n m p. rewrite (mul_comm n p), (mul_comm m p); apply mul_cancel_l. Qed. -Theorem NZmul_id_l : forall n m : NZ, m ~= 0 -> (n * m == m <-> n == 1). +Theorem mul_id_l : forall n m, m ~= 0 -> (n * m == m <-> n == 1). Proof. intros n m H. -stepl (n * m == 1 * m) by now rewrite NZmul_1_l. now apply NZmul_cancel_r. +stepl (n * m == 1 * m) by now rewrite mul_1_l. now apply mul_cancel_r. Qed. -Theorem NZmul_id_r : forall n m : NZ, n ~= 0 -> (n * m == n <-> m == 1). +Theorem mul_id_r : forall n m, n ~= 0 -> (n * m == n <-> m == 1). Proof. -intros n m; rewrite NZmul_comm; apply NZmul_id_l. +intros n m; rewrite mul_comm; apply mul_id_l. Qed. -Theorem NZmul_le_mono_pos_l : forall n m p : NZ, 0 < p -> (n <= m <-> p * n <= p * m). +Theorem mul_le_mono_pos_l : forall n m p, 0 < p -> (n <= m <-> p * n <= p * m). Proof. -intros n m p H; do 2 rewrite NZlt_eq_cases. -rewrite (NZmul_lt_mono_pos_l p n m) by assumption. -now rewrite -> (NZmul_cancel_l n m p) by -(intro H1; rewrite H1 in H; false_hyp H NZlt_irrefl). +intros n m p H; do 2 rewrite lt_eq_cases. +rewrite (mul_lt_mono_pos_l p n m) by assumption. +now rewrite -> (mul_cancel_l n m p) by +(intro H1; rewrite H1 in H; false_hyp H lt_irrefl). Qed. -Theorem NZmul_le_mono_pos_r : forall n m p : NZ, 0 < p -> (n <= m <-> n * p <= m * p). +Theorem mul_le_mono_pos_r : forall n m p, 0 < p -> (n <= m <-> n * p <= m * p). Proof. -intros n m p. rewrite (NZmul_comm n p); rewrite (NZmul_comm m p); -apply NZmul_le_mono_pos_l. +intros n m p. rewrite (mul_comm n p), (mul_comm m p); apply mul_le_mono_pos_l. Qed. -Theorem NZmul_le_mono_neg_l : forall n m p : NZ, p < 0 -> (n <= m <-> p * m <= p * n). +Theorem mul_le_mono_neg_l : forall n m p, p < 0 -> (n <= m <-> p * m <= p * n). Proof. -intros n m p H; do 2 rewrite NZlt_eq_cases. -rewrite (NZmul_lt_mono_neg_l p n m); [| assumption]. -rewrite -> (NZmul_cancel_l m n p) by (intro H1; rewrite H1 in H; false_hyp H NZlt_irrefl). -now setoid_replace (n == m) with (m == n) using relation iff by (split; now intro). +intros n m p H; do 2 rewrite lt_eq_cases. +rewrite (mul_lt_mono_neg_l p n m); [| assumption]. +rewrite -> (mul_cancel_l m n p) + by (intro H1; rewrite H1 in H; false_hyp H lt_irrefl). +now setoid_replace (n == m) with (m == n) by (split; now intro). Qed. -Theorem NZmul_le_mono_neg_r : forall n m p : NZ, p < 0 -> (n <= m <-> m * p <= n * p). +Theorem mul_le_mono_neg_r : forall n m p, p < 0 -> (n <= m <-> m * p <= n * p). Proof. -intros n m p. rewrite (NZmul_comm n p); rewrite (NZmul_comm m p); -apply NZmul_le_mono_neg_l. +intros n m p. rewrite (mul_comm n p), (mul_comm m p); apply mul_le_mono_neg_l. Qed. -Theorem NZmul_lt_mono_nonneg : - forall n m p q : NZ, 0 <= n -> n < m -> 0 <= p -> p < q -> n * p < m * q. +Theorem mul_lt_mono_nonneg : + forall n m p q, 0 <= n -> n < m -> 0 <= p -> p < q -> n * p < m * q. Proof. intros n m p q H1 H2 H3 H4. -apply NZle_lt_trans with (m * p). -apply NZmul_le_mono_nonneg_r; [assumption | now apply NZlt_le_incl]. -apply -> NZmul_lt_mono_pos_l; [assumption | now apply NZle_lt_trans with n]. +apply le_lt_trans with (m * p). +apply mul_le_mono_nonneg_r; [assumption | now apply lt_le_incl]. +apply -> mul_lt_mono_pos_l; [assumption | now apply le_lt_trans with n]. Qed. (* There are still many variants of the theorem above. One can assume 0 < n or 0 < p or n <= m or p <= q. *) -Theorem NZmul_le_mono_nonneg : - forall n m p q : NZ, 0 <= n -> n <= m -> 0 <= p -> p <= q -> n * p <= m * q. +Theorem mul_le_mono_nonneg : + forall n m p q, 0 <= n -> n <= m -> 0 <= p -> p <= q -> n * p <= m * q. Proof. intros n m p q H1 H2 H3 H4. le_elim H2; le_elim H4. -apply NZlt_le_incl; now apply NZmul_lt_mono_nonneg. -rewrite <- H4; apply NZmul_le_mono_nonneg_r; [assumption | now apply NZlt_le_incl]. -rewrite <- H2; apply NZmul_le_mono_nonneg_l; [assumption | now apply NZlt_le_incl]. -rewrite H2; rewrite H4; now apply NZeq_le_incl. +apply lt_le_incl; now apply mul_lt_mono_nonneg. +rewrite <- H4; apply mul_le_mono_nonneg_r; [assumption | now apply lt_le_incl]. +rewrite <- H2; apply mul_le_mono_nonneg_l; [assumption | now apply lt_le_incl]. +rewrite H2; rewrite H4; now apply eq_le_incl. Qed. -Theorem NZmul_pos_pos : forall n m : NZ, 0 < n -> 0 < m -> 0 < n * m. +Theorem mul_pos_pos : forall n m, 0 < n -> 0 < m -> 0 < n * m. Proof. -intros n m H1 H2. -rewrite <- (NZmul_0_l m). now apply -> NZmul_lt_mono_pos_r. +intros n m H1 H2. rewrite <- (mul_0_l m). now apply -> mul_lt_mono_pos_r. Qed. -Theorem NZmul_neg_neg : forall n m : NZ, n < 0 -> m < 0 -> 0 < n * m. +Theorem mul_neg_neg : forall n m, n < 0 -> m < 0 -> 0 < n * m. Proof. -intros n m H1 H2. -rewrite <- (NZmul_0_l m). now apply -> NZmul_lt_mono_neg_r. +intros n m H1 H2. rewrite <- (mul_0_l m). now apply -> mul_lt_mono_neg_r. Qed. -Theorem NZmul_pos_neg : forall n m : NZ, 0 < n -> m < 0 -> n * m < 0. +Theorem mul_pos_neg : forall n m, 0 < n -> m < 0 -> n * m < 0. Proof. -intros n m H1 H2. -rewrite <- (NZmul_0_l m). now apply -> NZmul_lt_mono_neg_r. +intros n m H1 H2. rewrite <- (mul_0_l m). now apply -> mul_lt_mono_neg_r. Qed. -Theorem NZmul_neg_pos : forall n m : NZ, n < 0 -> 0 < m -> n * m < 0. +Theorem mul_neg_pos : forall n m, n < 0 -> 0 < m -> n * m < 0. Proof. -intros; rewrite NZmul_comm; now apply NZmul_pos_neg. +intros; rewrite mul_comm; now apply mul_pos_neg. Qed. -Theorem NZlt_1_mul_pos : forall n m : NZ, 1 < n -> 0 < m -> 1 < n * m. +Theorem lt_1_mul_pos : forall n m, 1 < n -> 0 < m -> 1 < n * m. Proof. -intros n m H1 H2. apply -> (NZmul_lt_mono_pos_r m) in H1. -rewrite NZmul_1_l in H1. now apply NZlt_1_l with m. +intros n m H1 H2. apply -> (mul_lt_mono_pos_r m) in H1. +rewrite mul_1_l in H1. now apply lt_1_l with m. assumption. Qed. -Theorem NZeq_mul_0 : forall n m : NZ, n * m == 0 <-> n == 0 \/ m == 0. +Theorem eq_mul_0 : forall n m, n * m == 0 <-> n == 0 \/ m == 0. Proof. intros n m; split. -intro H; destruct (NZlt_trichotomy n 0) as [H1 | [H1 | H1]]; -destruct (NZlt_trichotomy m 0) as [H2 | [H2 | H2]]; +intro H; destruct (lt_trichotomy n 0) as [H1 | [H1 | H1]]; +destruct (lt_trichotomy m 0) as [H2 | [H2 | H2]]; try (now right); try (now left). -exfalso; now apply (NZlt_neq 0 (n * m)); [apply NZmul_neg_neg |]. -exfalso; now apply (NZlt_neq (n * m) 0); [apply NZmul_neg_pos |]. -exfalso; now apply (NZlt_neq (n * m) 0); [apply NZmul_pos_neg |]. -exfalso; now apply (NZlt_neq 0 (n * m)); [apply NZmul_pos_pos |]. -intros [H | H]. now rewrite H, NZmul_0_l. now rewrite H, NZmul_0_r. +exfalso; now apply (lt_neq 0 (n * m)); [apply mul_neg_neg |]. +exfalso; now apply (lt_neq (n * m) 0); [apply mul_neg_pos |]. +exfalso; now apply (lt_neq (n * m) 0); [apply mul_pos_neg |]. +exfalso; now apply (lt_neq 0 (n * m)); [apply mul_pos_pos |]. +intros [H | H]. now rewrite H, mul_0_l. now rewrite H, mul_0_r. Qed. -Theorem NZneq_mul_0 : forall n m : NZ, n ~= 0 /\ m ~= 0 <-> n * m ~= 0. +Theorem neq_mul_0 : forall n m, n ~= 0 /\ m ~= 0 <-> n * m ~= 0. Proof. intros n m; split; intro H. -intro H1; apply -> NZeq_mul_0 in H1. tauto. +intro H1; apply -> eq_mul_0 in H1. tauto. split; intro H1; rewrite H1 in H; -(rewrite NZmul_0_l in H || rewrite NZmul_0_r in H); now apply H. +(rewrite mul_0_l in H || rewrite mul_0_r in H); now apply H. Qed. -Theorem NZeq_square_0 : forall n : NZ, n * n == 0 <-> n == 0. +Theorem eq_square_0 : forall n, n * n == 0 <-> n == 0. Proof. -intro n; rewrite NZeq_mul_0; tauto. +intro n; rewrite eq_mul_0; tauto. Qed. -Theorem NZeq_mul_0_l : forall n m : NZ, n * m == 0 -> m ~= 0 -> n == 0. +Theorem eq_mul_0_l : forall n m, n * m == 0 -> m ~= 0 -> n == 0. Proof. -intros n m H1 H2. apply -> NZeq_mul_0 in H1. destruct H1 as [H1 | H1]. +intros n m H1 H2. apply -> eq_mul_0 in H1. destruct H1 as [H1 | H1]. assumption. false_hyp H1 H2. Qed. -Theorem NZeq_mul_0_r : forall n m : NZ, n * m == 0 -> n ~= 0 -> m == 0. +Theorem eq_mul_0_r : forall n m, n * m == 0 -> n ~= 0 -> m == 0. Proof. -intros n m H1 H2; apply -> NZeq_mul_0 in H1. destruct H1 as [H1 | H1]. +intros n m H1 H2; apply -> eq_mul_0 in H1. destruct H1 as [H1 | H1]. false_hyp H1 H2. assumption. Qed. -Theorem NZlt_0_mul : forall n m : NZ, 0 < n * m <-> (0 < n /\ 0 < m) \/ (m < 0 /\ n < 0). +Theorem lt_0_mul : forall n m, 0 < n * m <-> (0 < n /\ 0 < m) \/ (m < 0 /\ n < 0). Proof. intros n m; split; [intro H | intros [[H1 H2] | [H1 H2]]]. -destruct (NZlt_trichotomy n 0) as [H1 | [H1 | H1]]; -[| rewrite H1 in H; rewrite NZmul_0_l in H; false_hyp H NZlt_irrefl |]; -(destruct (NZlt_trichotomy m 0) as [H2 | [H2 | H2]]; -[| rewrite H2 in H; rewrite NZmul_0_r in H; false_hyp H NZlt_irrefl |]); +destruct (lt_trichotomy n 0) as [H1 | [H1 | H1]]; +[| rewrite H1 in H; rewrite mul_0_l in H; false_hyp H lt_irrefl |]; +(destruct (lt_trichotomy m 0) as [H2 | [H2 | H2]]; +[| rewrite H2 in H; rewrite mul_0_r in H; false_hyp H lt_irrefl |]); try (left; now split); try (right; now split). -assert (H3 : n * m < 0) by now apply NZmul_neg_pos. -exfalso; now apply (NZlt_asymm (n * m) 0). -assert (H3 : n * m < 0) by now apply NZmul_pos_neg. -exfalso; now apply (NZlt_asymm (n * m) 0). -now apply NZmul_pos_pos. now apply NZmul_neg_neg. +assert (H3 : n * m < 0) by now apply mul_neg_pos. +exfalso; now apply (lt_asymm (n * m) 0). +assert (H3 : n * m < 0) by now apply mul_pos_neg. +exfalso; now apply (lt_asymm (n * m) 0). +now apply mul_pos_pos. now apply mul_neg_neg. Qed. -Theorem NZsquare_lt_mono_nonneg : forall n m : NZ, 0 <= n -> n < m -> n * n < m * m. +Theorem square_lt_mono_nonneg : forall n m, 0 <= n -> n < m -> n * n < m * m. Proof. -intros n m H1 H2. now apply NZmul_lt_mono_nonneg. +intros n m H1 H2. now apply mul_lt_mono_nonneg. Qed. -Theorem NZsquare_le_mono_nonneg : forall n m : NZ, 0 <= n -> n <= m -> n * n <= m * m. +Theorem square_le_mono_nonneg : forall n m, 0 <= n -> n <= m -> n * n <= m * m. Proof. -intros n m H1 H2. now apply NZmul_le_mono_nonneg. +intros n m H1 H2. now apply mul_le_mono_nonneg. Qed. (* The converse theorems require nonnegativity (or nonpositivity) of the other variable *) -Theorem NZsquare_lt_simpl_nonneg : forall n m : NZ, 0 <= m -> n * n < m * m -> n < m. +Theorem square_lt_simpl_nonneg : forall n m, 0 <= m -> n * n < m * m -> n < m. Proof. -intros n m H1 H2. destruct (NZlt_ge_cases n 0). -now apply NZlt_le_trans with 0. -destruct (NZlt_ge_cases n m). -assumption. assert (F : m * m <= n * n) by now apply NZsquare_le_mono_nonneg. -apply -> NZle_ngt in F. false_hyp H2 F. +intros n m H1 H2. destruct (lt_ge_cases n 0). +now apply lt_le_trans with 0. +destruct (lt_ge_cases n m). +assumption. assert (F : m * m <= n * n) by now apply square_le_mono_nonneg. +apply -> le_ngt in F. false_hyp H2 F. Qed. -Theorem NZsquare_le_simpl_nonneg : forall n m : NZ, 0 <= m -> n * n <= m * m -> n <= m. +Theorem square_le_simpl_nonneg : forall n m, 0 <= m -> n * n <= m * m -> n <= m. Proof. -intros n m H1 H2. destruct (NZlt_ge_cases n 0). -apply NZlt_le_incl; now apply NZlt_le_trans with 0. -destruct (NZle_gt_cases n m). -assumption. assert (F : m * m < n * n) by now apply NZsquare_lt_mono_nonneg. -apply -> NZlt_nge in F. false_hyp H2 F. +intros n m H1 H2. destruct (lt_ge_cases n 0). +apply lt_le_incl; now apply lt_le_trans with 0. +destruct (le_gt_cases n m). +assumption. assert (F : m * m < n * n) by now apply square_lt_mono_nonneg. +apply -> lt_nge in F. false_hyp H2 F. Qed. -Theorem NZmul_2_mono_l : forall n m : NZ, n < m -> 1 + (1 + 1) * n < (1 + 1) * m. +Theorem mul_2_mono_l : forall n m, n < m -> 1 + (1 + 1) * n < (1 + 1) * m. Proof. -intros n m H. apply <- NZle_succ_l in H. -apply -> (NZmul_le_mono_pos_l (S n) m (1 + 1)) in H. -repeat rewrite NZmul_add_distr_r in *; repeat rewrite NZmul_1_l in *. -repeat rewrite NZadd_succ_r in *. repeat rewrite NZadd_succ_l in *. rewrite NZadd_0_l. -now apply -> NZle_succ_l. -apply NZadd_pos_pos; now apply NZlt_succ_diag_r. +intros n m. rewrite <- le_succ_l, (mul_le_mono_pos_l (S n) m (1 + 1)). +rewrite !mul_add_distr_r; nzsimpl; now rewrite le_succ_l. +apply add_pos_pos; now apply lt_0_1. Qed. End NZMulOrderPropFunct. diff --git a/theories/Numbers/NatInt/NZOrder.v b/theories/Numbers/NatInt/NZOrder.v index 85b284a72..4c54cc3b8 100644 --- a/theories/Numbers/NatInt/NZOrder.v +++ b/theories/Numbers/NatInt/NZOrder.v @@ -13,648 +13,663 @@ Require Import NZAxioms. Require Import NZMul. Require Import Decidable. +Require Import OrderTac. -Module NZOrderPropFunct (Import NZOrdAxiomsMod : NZOrdAxiomsSig). -Module Export NZMulPropMod := NZMulPropFunct NZAxiomsMod. -Open Local Scope NatIntScope. +Module NZOrderPropFunct (Import NZ : NZOrdAxiomsSig). +Include NZMulPropFunct NZ. (* In fact only NZBase is used here *) +Local Open Scope NumScope. -Ltac le_elim H := rewrite NZlt_eq_cases in H; destruct H as [H | H]. - -Theorem NZlt_le_incl : forall n m : NZ, n < m -> n <= m. +Instance le_wd : Proper (eq==>eq==>iff) le. Proof. -intros; apply <- NZlt_eq_cases; now left. +intros n n' Hn m m' Hm. rewrite !lt_eq_cases, !Hn, !Hm; auto with *. Qed. -Theorem NZeq_le_incl : forall n m : NZ, n == m -> n <= m. -Proof. -intros; apply <- NZlt_eq_cases; now right. -Qed. +Ltac le_elim H := rewrite lt_eq_cases in H; destruct H as [H | H]. -Lemma NZlt_stepl : forall x y z : NZ, x < y -> x == z -> z < y. +Theorem lt_le_incl : forall n m, n < m -> n <= m. Proof. -intros x y z H1 H2; now rewrite <- H2. +intros; apply <- lt_eq_cases; now left. Qed. -Lemma NZlt_stepr : forall x y z : NZ, x < y -> y == z -> x < z. +Theorem le_refl : forall n, n <= n. Proof. -intros x y z H1 H2; now rewrite <- H2. +intro; apply <- lt_eq_cases; now right. Qed. -Lemma NZle_stepl : forall x y z : NZ, x <= y -> x == z -> z <= y. +Theorem lt_succ_diag_r : forall n, n < S n. Proof. -intros x y z H1 H2; now rewrite <- H2. +intro n. rewrite lt_succ_r. apply le_refl. Qed. -Lemma NZle_stepr : forall x y z : NZ, x <= y -> y == z -> x <= z. +Theorem le_succ_diag_r : forall n, n <= S n. Proof. -intros x y z H1 H2; now rewrite <- H2. +intro; apply lt_le_incl; apply lt_succ_diag_r. Qed. -Declare Left Step NZlt_stepl. -Declare Right Step NZlt_stepr. -Declare Left Step NZle_stepl. -Declare Right Step NZle_stepr. - -Theorem NZlt_neq : forall n m : NZ, n < m -> n ~= m. +Theorem neq_succ_diag_l : forall n, S n ~= n. Proof. -intros n m H1 H2; rewrite H2 in H1; false_hyp H1 NZlt_irrefl. +intros n H. apply (lt_irrefl n). rewrite <- H at 2. apply lt_succ_diag_r. Qed. -Theorem NZle_neq : forall n m : NZ, n < m <-> n <= m /\ n ~= m. +Theorem neq_succ_diag_r : forall n, n ~= S n. Proof. -intros n m; split; [intro H | intros [H1 H2]]. -split. now apply NZlt_le_incl. now apply NZlt_neq. -le_elim H1. assumption. false_hyp H1 H2. +intro n; apply neq_sym, neq_succ_diag_l. Qed. -Theorem NZle_refl : forall n : NZ, n <= n. +Theorem nlt_succ_diag_l : forall n, ~ S n < n. Proof. -intro; now apply NZeq_le_incl. +intros n H. apply (lt_irrefl (S n)). rewrite lt_succ_r. now apply lt_le_incl. Qed. -Theorem NZlt_succ_diag_r : forall n : NZ, n < S n. +Theorem nle_succ_diag_l : forall n, ~ S n <= n. Proof. -intro n. rewrite NZlt_succ_r. now apply NZeq_le_incl. +intros n H; le_elim H. +false_hyp H nlt_succ_diag_l. false_hyp H neq_succ_diag_l. Qed. -Theorem NZle_succ_diag_r : forall n : NZ, n <= S n. +Theorem le_succ_l : forall n m, S n <= m <-> n < m. Proof. -intro; apply NZlt_le_incl; apply NZlt_succ_diag_r. +intro n; nzinduct m n. +split; intro H. false_hyp H nle_succ_diag_l. false_hyp H lt_irrefl. +intro m. +rewrite (lt_eq_cases (S n) (S m)), !lt_succ_r, (lt_eq_cases n m), succ_inj_wd. +rewrite or_cancel_r. +reflexivity. +intros LE EQ; rewrite EQ in LE; false_hyp LE nle_succ_diag_l. +intros LT EQ; rewrite EQ in LT; false_hyp LT lt_irrefl. Qed. -Theorem NZlt_0_1 : 0 < 1. -Proof. -apply NZlt_succ_diag_r. -Qed. +(** Trichotomy *) -Theorem NZle_0_1 : 0 <= 1. +Theorem le_gt_cases : forall n m, n <= m \/ n > m. Proof. -apply NZle_succ_diag_r. +intros n m; nzinduct n m. +left; apply le_refl. +intro n. rewrite lt_succ_r, le_succ_l, !lt_eq_cases. intuition. Qed. -Theorem NZlt_lt_succ_r : forall n m : NZ, n < m -> n < S m. +Theorem lt_trichotomy : forall n m, n < m \/ n == m \/ m < n. Proof. -intros. rewrite NZlt_succ_r. now apply NZlt_le_incl. +intros n m. generalize (le_gt_cases n m); rewrite lt_eq_cases; tauto. Qed. -Theorem NZle_le_succ_r : forall n m : NZ, n <= m -> n <= S m. -Proof. -intros n m H. rewrite <- NZlt_succ_r in H. now apply NZlt_le_incl. -Qed. +Notation lt_eq_gt_cases := lt_trichotomy (only parsing). + +(** Asymmetry and transitivity. *) -Theorem NZle_succ_r : forall n m : NZ, n <= S m <-> n <= m \/ n == S m. +Theorem lt_asymm : forall n m, n < m -> ~ m < n. Proof. -intros n m; rewrite NZlt_eq_cases. now rewrite NZlt_succ_r. +intros n m; nzinduct n m. +intros H; false_hyp H lt_irrefl. +intro n; split; intros H H1 H2. +apply lt_succ_r in H2. le_elim H2. +apply H; auto. apply -> le_succ_l. now apply lt_le_incl. +rewrite H2 in H1. false_hyp H1 nlt_succ_diag_l. +apply le_succ_l in H1. le_elim H1. +apply H; auto. rewrite lt_succ_r. now apply lt_le_incl. +rewrite <- H1 in H2. false_hyp H2 nlt_succ_diag_l. Qed. -(* The following theorem is a special case of neq_succ_iter_l below, -but we prove it separately *) +Notation lt_ngt := lt_asymm (only parsing). -Theorem NZneq_succ_diag_l : forall n : NZ, S n ~= n. +Theorem lt_trans : forall n m p, n < m -> m < p -> n < p. Proof. -intros n H. pose proof (NZlt_succ_diag_r n) as H1. rewrite H in H1. -false_hyp H1 NZlt_irrefl. +intros n m p; nzinduct p m. +intros _ H; false_hyp H lt_irrefl. +intro p. rewrite 2 lt_succ_r. +split; intros H H1 H2. +apply lt_le_incl; le_elim H2; [now apply H | now rewrite H2 in H1]. +assert (n <= p) as H3 by (auto using lt_le_incl). +le_elim H3. assumption. rewrite <- H3 in H2. +elim (lt_asymm n m); auto. Qed. -Theorem NZneq_succ_diag_r : forall n : NZ, n ~= S n. -Proof. -intro n; apply NZneq_sym; apply NZneq_succ_diag_l. -Qed. +(** We know enough now to benefit from the generic [order] tactic. *) -Theorem NZnlt_succ_diag_l : forall n : NZ, ~ S n < n. -Proof. -intros n H; apply NZlt_lt_succ_r in H. false_hyp H NZlt_irrefl. -Qed. +Module OrderElts. + Definition t := t. + Definition eq := eq. + Definition lt := lt. + Definition le := le. + Instance eq_equiv : Equivalence eq. + Instance lt_strorder : StrictOrder lt. + Proof. split; [ exact lt_irrefl | exact lt_trans ]. Qed. + Instance lt_compat : Proper (eq==>eq==>iff) lt. + Proof. exact lt_wd. Qed. (* BUG(?) pourquoi ne trouve-t'il pas lt_wd *) + Definition lt_total := lt_trichotomy. + Definition le_lteq := lt_eq_cases. +End OrderElts. +Module OrderTac := MakeOrderTac OrderElts. +Ltac order := + change eq with OrderElts.eq in *; + change lt with OrderElts.lt in *; + change le with OrderElts.le in *; + OrderTac.order. -Theorem NZnle_succ_diag_l : forall n : NZ, ~ S n <= n. -Proof. -intros n H; le_elim H. -false_hyp H NZnlt_succ_diag_l. false_hyp H NZneq_succ_diag_l. -Qed. +(** Some direct consequences of [order]. *) + +Theorem lt_neq : forall n m, n < m -> n ~= m. +Proof. order. Qed. + +Theorem le_neq : forall n m, n < m <-> n <= m /\ n ~= m. +Proof. intuition order. Qed. + +Theorem eq_le_incl : forall n m, n == m -> n <= m. +Proof. order. Qed. + +Lemma lt_stepl : forall x y z, x < y -> x == z -> z < y. +Proof. order. Qed. + +Lemma lt_stepr : forall x y z, x < y -> y == z -> x < z. +Proof. order. Qed. + +Lemma le_stepl : forall x y z, x <= y -> x == z -> z <= y. +Proof. order. Qed. + +Lemma le_stepr : forall x y z, x <= y -> y == z -> x <= z. +Proof. order. Qed. + +Declare Left Step lt_stepl. +Declare Right Step lt_stepr. +Declare Left Step le_stepl. +Declare Right Step le_stepr. -Theorem NZle_succ_l : forall n m : NZ, S n <= m <-> n < m. +Theorem le_trans : forall n m p, n <= m -> m <= p -> n <= p. +Proof. order. Qed. + +Theorem le_lt_trans : forall n m p, n <= m -> m < p -> n < p. +Proof. order. Qed. + +Theorem lt_le_trans : forall n m p, n < m -> m <= p -> n < p. +Proof. order. Qed. + +Theorem le_antisymm : forall n m, n <= m -> m <= n -> n == m. +Proof. order. Qed. + +(** More properties of [<] and [<=] with respect to [S] and [0]. *) + +Theorem le_succ_r : forall n m, n <= S m <-> n <= m \/ n == S m. Proof. -intro n; NZinduct m n. -setoid_replace (n < n) with False using relation iff by - (apply -> neg_false; apply NZlt_irrefl). -now setoid_replace (S n <= n) with False using relation iff by - (apply -> neg_false; apply NZnle_succ_diag_l). -intro m. rewrite NZlt_succ_r. rewrite NZle_succ_r. -rewrite NZsucc_inj_wd. -rewrite (NZlt_eq_cases n m). -rewrite or_cancel_r. -reflexivity. -intros H1 H2; rewrite H2 in H1; false_hyp H1 NZnle_succ_diag_l. -apply NZlt_neq. +intros n m; rewrite lt_eq_cases. now rewrite lt_succ_r. Qed. -Theorem NZlt_succ_l : forall n m : NZ, S n < m -> n < m. +Theorem lt_succ_l : forall n m, S n < m -> n < m. Proof. -intros n m H; apply -> NZle_succ_l; now apply NZlt_le_incl. +intros n m H; apply -> le_succ_l; now apply lt_le_incl. Qed. -Theorem NZsucc_lt_mono : forall n m : NZ, n < m <-> S n < S m. +Theorem le_le_succ_r : forall n m, n <= m -> n <= S m. Proof. -intros n m. rewrite <- NZle_succ_l. symmetry. apply NZlt_succ_r. +intros n m LE. rewrite <- lt_succ_r in LE. now apply lt_le_incl. Qed. -Theorem NZsucc_le_mono : forall n m : NZ, n <= m <-> S n <= S m. +Theorem lt_lt_succ_r : forall n m, n < m -> n < S m. Proof. -intros n m. do 2 rewrite NZlt_eq_cases. -rewrite <- NZsucc_lt_mono; now rewrite NZsucc_inj_wd. +intros. rewrite lt_succ_r. now apply lt_le_incl. Qed. -Theorem NZlt_asymm : forall n m, n < m -> ~ m < n. +Theorem succ_lt_mono : forall n m, n < m <-> S n < S m. Proof. -intros n m; NZinduct n m. -intros H _; false_hyp H NZlt_irrefl. -intro n; split; intros H H1 H2. -apply NZlt_succ_l in H1. apply -> NZlt_succ_r in H2. le_elim H2. -now apply H. rewrite H2 in H1; false_hyp H1 NZlt_irrefl. -apply NZlt_lt_succ_r in H2. apply <- NZle_succ_l in H1. le_elim H1. -now apply H. rewrite H1 in H2; false_hyp H2 NZlt_irrefl. +intros n m. rewrite <- le_succ_l. symmetry. apply lt_succ_r. Qed. -Theorem NZlt_trans : forall n m p : NZ, n < m -> m < p -> n < p. +Theorem succ_le_mono : forall n m, n <= m <-> S n <= S m. Proof. -intros n m p; NZinduct p m. -intros _ H; false_hyp H NZlt_irrefl. -intro p. do 2 rewrite NZlt_succ_r. -split; intros H H1 H2. -apply NZlt_le_incl; le_elim H2; [now apply H | now rewrite H2 in H1]. -assert (n <= p) as H3. apply H. assumption. now apply NZlt_le_incl. -le_elim H3. assumption. rewrite <- H3 in H2. -exfalso; now apply (NZlt_asymm n m). +intros n m. now rewrite 2 lt_eq_cases, <- succ_lt_mono, succ_inj_wd. Qed. -Theorem NZle_trans : forall n m p : NZ, n <= m -> m <= p -> n <= p. +Theorem lt_0_1 : 0 < 1. Proof. -intros n m p H1 H2; le_elim H1. -le_elim H2. apply NZlt_le_incl; now apply NZlt_trans with (m := m). -apply NZlt_le_incl; now rewrite <- H2. now rewrite H1. +apply lt_succ_diag_r. Qed. -Theorem NZle_lt_trans : forall n m p : NZ, n <= m -> m < p -> n < p. +Theorem le_0_1 : 0 <= 1. Proof. -intros n m p H1 H2; le_elim H1. -now apply NZlt_trans with (m := m). now rewrite H1. +apply le_succ_diag_r. Qed. -Theorem NZlt_le_trans : forall n m p : NZ, n < m -> m <= p -> n < p. +Theorem lt_1_l : forall n m, 0 < n -> n < m -> 1 < m. Proof. -intros n m p H1 H2; le_elim H2. -now apply NZlt_trans with (m := m). now rewrite <- H2. +intros n m H1 H2. apply <- le_succ_l in H1. now apply le_lt_trans with n. Qed. -Theorem NZle_antisymm : forall n m : NZ, n <= m -> m <= n -> n == m. + +(** More Trichotomy, decidability and double negation elimination. *) + +(** The following theorem is cleary redundant, but helps not to +remember whether one has to say le_gt_cases or lt_ge_cases *) + +Theorem lt_ge_cases : forall n m, n < m \/ n >= m. Proof. -intros n m H1 H2; now (le_elim H1; le_elim H2); -[exfalso; apply (NZlt_asymm n m) | | |]. +intros n m; destruct (le_gt_cases m n); [right|left]; order. Qed. -Theorem NZlt_1_l : forall n m : NZ, 0 < n -> n < m -> 1 < m. +Theorem le_ge_cases : forall n m, n <= m \/ n >= m. Proof. -intros n m H1 H2. apply <- NZle_succ_l in H1. now apply NZle_lt_trans with n. +intros n m; destruct (le_gt_cases n m); [left|right]; order. Qed. -(** Trichotomy, decidability, and double negation elimination *) - -Theorem NZlt_trichotomy : forall n m : NZ, n < m \/ n == m \/ m < n. +Theorem lt_gt_cases : forall n m, n ~= m <-> n < m \/ n > m. Proof. -intros n m; NZinduct n m. -right; now left. -intro n; rewrite NZlt_succ_r. stepr ((S n < m \/ S n == m) \/ m <= n) by tauto. -rewrite <- (NZlt_eq_cases (S n) m). -setoid_replace (n == m) with (m == n) using relation iff by now split. -stepl (n < m \/ m < n \/ m == n) by tauto. rewrite <- NZlt_eq_cases. -apply or_iff_compat_r. symmetry; apply NZle_succ_l. +intros n m; destruct (lt_trichotomy n m); intuition order. Qed. -(* Decidability of equality, even though true in each finite ring, does not +(** Decidability of equality, even though true in each finite ring, does not have a uniform proof. Otherwise, the proof for two fixed numbers would reduce to a normal form that will say if the numbers are equal or not, which cannot be true in all finite rings. Therefore, we prove decidability in the presence of order. *) -Theorem NZeq_dec : forall n m : NZ, decidable (n == m). +Theorem eq_dec : forall n m, decidable (n == m). Proof. -intros n m; destruct (NZlt_trichotomy n m) as [H | [H | H]]. -right; intro H1; rewrite H1 in H; false_hyp H NZlt_irrefl. -now left. -right; intro H1; rewrite H1 in H; false_hyp H NZlt_irrefl. +intros n m; destruct (lt_trichotomy n m) as [ | [ | ]]; + (right; order) || (left; order). Qed. -(* DNE stands for double-negation elimination *) +(** DNE stands for double-negation elimination *) -Theorem NZeq_dne : forall n m, ~ ~ n == m <-> n == m. +Theorem eq_dne : forall n m, ~ ~ n == m <-> n == m. Proof. intros n m; split; intro H. -destruct (NZeq_dec n m) as [H1 | H1]. +destruct (eq_dec n m) as [H1 | H1]. assumption. false_hyp H1 H. intro H1; now apply H1. Qed. -Theorem NZlt_gt_cases : forall n m : NZ, n ~= m <-> n < m \/ n > m. -Proof. -intros n m; split. -pose proof (NZlt_trichotomy n m); tauto. -intros H H1; destruct H as [H | H]; rewrite H1 in H; false_hyp H NZlt_irrefl. -Qed. - -Theorem NZle_gt_cases : forall n m : NZ, n <= m \/ n > m. -Proof. -intros n m; destruct (NZlt_trichotomy n m) as [H | [H | H]]. -left; now apply NZlt_le_incl. left; now apply NZeq_le_incl. now right. -Qed. - -(* The following theorem is cleary redundant, but helps not to -remember whether one has to say le_gt_cases or lt_ge_cases *) - -Theorem NZlt_ge_cases : forall n m : NZ, n < m \/ n >= m. -Proof. -intros n m; destruct (NZle_gt_cases m n); try (now left); try (now right). -Qed. - -Theorem NZle_ge_cases : forall n m : NZ, n <= m \/ n >= m. -Proof. -intros n m; destruct (NZle_gt_cases n m) as [H | H]. -now left. right; now apply NZlt_le_incl. -Qed. - -Theorem NZle_ngt : forall n m : NZ, n <= m <-> ~ n > m. -Proof. -intros n m. split; intro H; [intro H1 |]. -eapply NZle_lt_trans in H; [| eassumption ..]. false_hyp H NZlt_irrefl. -destruct (NZle_gt_cases n m) as [H1 | H1]. -assumption. false_hyp H1 H. -Qed. +Theorem le_ngt : forall n m, n <= m <-> ~ n > m. +Proof. intuition order. Qed. -(* Redundant but useful *) +(** Redundant but useful *) -Theorem NZnlt_ge : forall n m : NZ, ~ n < m <-> n >= m. -Proof. -intros n m; symmetry; apply NZle_ngt. -Qed. +Theorem nlt_ge : forall n m, ~ n < m <-> n >= m. +Proof. intuition order. Qed. -Theorem NZlt_dec : forall n m : NZ, decidable (n < m). +Theorem lt_dec : forall n m, decidable (n < m). Proof. -intros n m; destruct (NZle_gt_cases m n); -[right; now apply -> NZle_ngt | now left]. +intros n m; destruct (le_gt_cases m n); [right|left]; order. Qed. -Theorem NZlt_dne : forall n m, ~ ~ n < m <-> n < m. +Theorem lt_dne : forall n m, ~ ~ n < m <-> n < m. Proof. -intros n m; split; intro H; -[destruct (NZlt_dec n m) as [H1 | H1]; [assumption | false_hyp H1 H] | -intro H1; false_hyp H H1]. +intros n m; split; intro H. +destruct (lt_dec n m) as [H1 | H1]; [assumption | false_hyp H1 H]. +intro H1; false_hyp H H1. Qed. -Theorem NZnle_gt : forall n m : NZ, ~ n <= m <-> n > m. -Proof. -intros n m. rewrite NZle_ngt. apply NZlt_dne. -Qed. +Theorem nle_gt : forall n m, ~ n <= m <-> n > m. +Proof. intuition order. Qed. -(* Redundant but useful *) +(** Redundant but useful *) -Theorem NZlt_nge : forall n m : NZ, n < m <-> ~ n >= m. -Proof. -intros n m; symmetry; apply NZnle_gt. -Qed. +Theorem lt_nge : forall n m, n < m <-> ~ n >= m. +Proof. intuition order. Qed. -Theorem NZle_dec : forall n m : NZ, decidable (n <= m). +Theorem le_dec : forall n m, decidable (n <= m). Proof. -intros n m; destruct (NZle_gt_cases n m); -[now left | right; now apply <- NZnle_gt]. +intros n m; destruct (le_gt_cases n m); [left|right]; order. Qed. -Theorem NZle_dne : forall n m : NZ, ~ ~ n <= m <-> n <= m. +Theorem le_dne : forall n m, ~ ~ n <= m <-> n <= m. Proof. -intros n m; split; intro H; -[destruct (NZle_dec n m) as [H1 | H1]; [assumption | false_hyp H1 H] | -intro H1; false_hyp H H1]. +intros n m; split; intro H. +destruct (le_dec n m) as [H1 | H1]; [assumption | false_hyp H1 H]. +intro H1; false_hyp H H1. Qed. -Theorem NZnlt_succ_r : forall n m : NZ, ~ m < S n <-> n < m. +Theorem nlt_succ_r : forall n m, ~ m < S n <-> n < m. Proof. -intros n m; rewrite NZlt_succ_r; apply NZnle_gt. +intros n m; rewrite lt_succ_r; apply nle_gt. Qed. -(* The difference between integers and natural numbers is that for +(** The difference between integers and natural numbers is that for every integer there is a predecessor, which is not true for natural numbers. However, for both classes, every number that is bigger than some other number has a predecessor. The proof of this fact by regular induction does not go through, so we need to use strong (course-of-value) induction. *) -Lemma NZlt_exists_pred_strong : - forall z n m : NZ, z < m -> m <= n -> exists k : NZ, m == S k /\ z <= k. +Lemma lt_exists_pred_strong : + forall z n m, z < m -> m <= n -> exists k, m == S k /\ z <= k. Proof. -intro z; NZinduct n z. -intros m H1 H2; apply <- NZnle_gt in H1; false_hyp H2 H1. +intro z; nzinduct n z. +order. intro n; split; intros IH m H1 H2. -apply -> NZle_succ_r in H2; destruct H2 as [H2 | H2]. -now apply IH. exists n. now split; [| rewrite <- NZlt_succ_r; rewrite <- H2]. -apply IH. assumption. now apply NZle_le_succ_r. +apply -> le_succ_r in H2. destruct H2 as [H2 | H2]. +now apply IH. exists n. now split; [| rewrite <- lt_succ_r; rewrite <- H2]. +apply IH. assumption. now apply le_le_succ_r. Qed. -Theorem NZlt_exists_pred : - forall z n : NZ, z < n -> exists k : NZ, n == S k /\ z <= k. +Theorem lt_exists_pred : + forall z n, z < n -> exists k, n == S k /\ z <= k. Proof. -intros z n H; apply NZlt_exists_pred_strong with (z := z) (n := n). -assumption. apply NZle_refl. +intros z n H; apply lt_exists_pred_strong with (z := z) (n := n). +assumption. apply le_refl. Qed. (** A corollary of having an order is that NZ is infinite *) -(* This section about infinity of NZ relies on the type nat and can be +(** This section about infinity of NZ relies on the type nat and can be safely removed *) -Definition NZsucc_iter (n : nat) (m : NZ) := - nat_rect (fun _ => NZ) m (fun _ l => S l) n. +Fixpoint of_nat (n : nat) : t := + match n with + | O => 0 + | Datatypes.S n' => S (of_nat n') + end. -Theorem NZlt_succ_iter_r : - forall (n : nat) (m : NZ), m < NZsucc_iter (Datatypes.S n) m. +Theorem of_nat_S_gt_0 : + forall (n : nat), 0 < of_nat (Datatypes.S n). Proof. -intros n m; induction n as [| n IH]; simpl in *. -apply NZlt_succ_diag_r. now apply NZlt_lt_succ_r. +intros n; induction n as [| n IH]; simpl in *. +apply lt_0_1. +apply lt_trans with 1. apply lt_0_1. now rewrite <- succ_lt_mono. Qed. -Theorem NZneq_succ_iter_l : - forall (n : nat) (m : NZ), NZsucc_iter (Datatypes.S n) m ~= m. +Theorem of_nat_S_neq_0 : + forall (n : nat), 0 ~= of_nat (Datatypes.S n). Proof. -intros n m H. pose proof (NZlt_succ_iter_r n m) as H1. rewrite H in H1. -false_hyp H1 NZlt_irrefl. +intros. apply lt_neq, of_nat_S_gt_0. Qed. -(* End of the section about the infinity of NZ *) +Lemma of_nat_injective : forall n m, of_nat n == of_nat m -> n = m. +Proof. +induction n as [|n IH]; destruct m; auto. +intros H; elim (of_nat_S_neq_0 _ H). +intros H; symmetry in H; elim (of_nat_S_neq_0 _ H). +intros. f_equal. apply IH. now rewrite <- succ_inj_wd. +(* BUG: succ_inj_wd n'est pas vu par SearchAbout *) +Qed. + +(** End of the section about the infinity of NZ *) (** Stronger variant of induction with assumptions n >= 0 (n < 0) in the induction step *) Section Induction. -Variable A : NZ -> Prop. -Hypothesis A_wd : Proper (NZeq==>iff) A. +Variable A : t -> Prop. +Hypothesis A_wd : Proper (eq==>iff) A. Section Center. -Variable z : NZ. (* A z is the basis of induction *) +Variable z : t. (* A z is the basis of induction *) Section RightInduction. -Let A' (n : NZ) := forall m : NZ, z <= m -> m < n -> A m. -Let right_step := forall n : NZ, z <= n -> A n -> A (S n). -Let right_step' := forall n : NZ, z <= n -> A' n -> A n. -Let right_step'' := forall n : NZ, A' n <-> A' (S n). +Let A' (n : t) := forall m, z <= m -> m < n -> A m. +Let right_step := forall n, z <= n -> A n -> A (S n). +Let right_step' := forall n, z <= n -> A' n -> A n. +Let right_step'' := forall n, A' n <-> A' (S n). -Lemma NZrs_rs' : A z -> right_step -> right_step'. +Lemma rs_rs' : A z -> right_step -> right_step'. Proof. intros Az RS n H1 H2. -le_elim H1. apply NZlt_exists_pred in H1. destruct H1 as [k [H3 H4]]. -rewrite H3. apply RS; [assumption | apply H2; [assumption | rewrite H3; apply NZlt_succ_diag_r]]. +le_elim H1. apply lt_exists_pred in H1. destruct H1 as [k [H3 H4]]. +rewrite H3. apply RS; trivial. apply H2; trivial. +rewrite H3; apply lt_succ_diag_r. rewrite <- H1; apply Az. Qed. -Lemma NZrs'_rs'' : right_step' -> right_step''. +Lemma rs'_rs'' : right_step' -> right_step''. Proof. intros RS' n; split; intros H1 m H2 H3. -apply -> NZlt_succ_r in H3; le_elim H3; +apply -> lt_succ_r in H3; le_elim H3; [now apply H1 | rewrite H3 in *; now apply RS']. -apply H1; [assumption | now apply NZlt_lt_succ_r]. +apply H1; [assumption | now apply lt_lt_succ_r]. Qed. -Lemma NZrbase : A' z. +Lemma rbase : A' z. Proof. -intros m H1 H2. apply -> NZle_ngt in H1. false_hyp H2 H1. +intros m H1 H2. apply -> le_ngt in H1. false_hyp H2 H1. Qed. -Lemma NZA'A_right : (forall n : NZ, A' n) -> forall n : NZ, z <= n -> A n. +Lemma A'A_right : (forall n, A' n) -> forall n, z <= n -> A n. Proof. -intros H1 n H2. apply H1 with (n := S n); [assumption | apply NZlt_succ_diag_r]. +intros H1 n H2. apply H1 with (n := S n); [assumption | apply lt_succ_diag_r]. Qed. -Theorem NZstrong_right_induction: right_step' -> forall n : NZ, z <= n -> A n. +Theorem strong_right_induction: right_step' -> forall n, z <= n -> A n. Proof. -intro RS'; apply NZA'A_right; unfold A'; NZinduct n z; -[apply NZrbase | apply NZrs'_rs''; apply RS']. +intro RS'; apply A'A_right; unfold A'; nzinduct n z; +[apply rbase | apply rs'_rs''; apply RS']. Qed. -Theorem NZright_induction : A z -> right_step -> forall n : NZ, z <= n -> A n. +Theorem right_induction : A z -> right_step -> forall n, z <= n -> A n. Proof. -intros Az RS; apply NZstrong_right_induction; now apply NZrs_rs'. +intros Az RS; apply strong_right_induction; now apply rs_rs'. Qed. -Theorem NZright_induction' : - (forall n : NZ, n <= z -> A n) -> right_step -> forall n : NZ, A n. +Theorem right_induction' : + (forall n, n <= z -> A n) -> right_step -> forall n, A n. Proof. intros L R n. -destruct (NZlt_trichotomy n z) as [H | [H | H]]. -apply L; now apply NZlt_le_incl. -apply L; now apply NZeq_le_incl. -apply NZright_induction. apply L; now apply NZeq_le_incl. assumption. now apply NZlt_le_incl. +destruct (lt_trichotomy n z) as [H | [H | H]]. +apply L; now apply lt_le_incl. +apply L; now apply eq_le_incl. +apply right_induction. apply L; now apply eq_le_incl. assumption. +now apply lt_le_incl. Qed. -Theorem NZstrong_right_induction' : - (forall n : NZ, n <= z -> A n) -> right_step' -> forall n : NZ, A n. +Theorem strong_right_induction' : + (forall n, n <= z -> A n) -> right_step' -> forall n, A n. Proof. intros L R n. -destruct (NZlt_trichotomy n z) as [H | [H | H]]. -apply L; now apply NZlt_le_incl. -apply L; now apply NZeq_le_incl. -apply NZstrong_right_induction. assumption. now apply NZlt_le_incl. +destruct (lt_trichotomy n z) as [H | [H | H]]. +apply L; now apply lt_le_incl. +apply L; now apply eq_le_incl. +apply strong_right_induction. assumption. now apply lt_le_incl. Qed. End RightInduction. Section LeftInduction. -Let A' (n : NZ) := forall m : NZ, m <= z -> n <= m -> A m. -Let left_step := forall n : NZ, n < z -> A (S n) -> A n. -Let left_step' := forall n : NZ, n <= z -> A' (S n) -> A n. -Let left_step'' := forall n : NZ, A' n <-> A' (S n). +Let A' (n : t) := forall m, m <= z -> n <= m -> A m. +Let left_step := forall n, n < z -> A (S n) -> A n. +Let left_step' := forall n, n <= z -> A' (S n) -> A n. +Let left_step'' := forall n, A' n <-> A' (S n). -Lemma NZls_ls' : A z -> left_step -> left_step'. +Lemma ls_ls' : A z -> left_step -> left_step'. Proof. intros Az LS n H1 H2. le_elim H1. -apply LS; [assumption | apply H2; [now apply <- NZle_succ_l | now apply NZeq_le_incl]]. +apply LS; trivial. apply H2; [now apply <- le_succ_l | now apply eq_le_incl]. rewrite H1; apply Az. Qed. -Lemma NZls'_ls'' : left_step' -> left_step''. +Lemma ls'_ls'' : left_step' -> left_step''. Proof. intros LS' n; split; intros H1 m H2 H3. -apply -> NZle_succ_l in H3. apply NZlt_le_incl in H3. now apply H1. +apply -> le_succ_l in H3. apply lt_le_incl in H3. now apply H1. le_elim H3. -apply <- NZle_succ_l in H3. now apply H1. +apply <- le_succ_l in H3. now apply H1. rewrite <- H3 in *; now apply LS'. Qed. -Lemma NZlbase : A' (S z). +Lemma lbase : A' (S z). Proof. -intros m H1 H2. apply -> NZle_succ_l in H2. -apply -> NZle_ngt in H1. false_hyp H2 H1. +intros m H1 H2. apply -> le_succ_l in H2. +apply -> le_ngt in H1. false_hyp H2 H1. Qed. -Lemma NZA'A_left : (forall n : NZ, A' n) -> forall n : NZ, n <= z -> A n. +Lemma A'A_left : (forall n, A' n) -> forall n, n <= z -> A n. Proof. -intros H1 n H2. apply H1 with (n := n); [assumption | now apply NZeq_le_incl]. +intros H1 n H2. apply H1 with (n := n); [assumption | now apply eq_le_incl]. Qed. -Theorem NZstrong_left_induction: left_step' -> forall n : NZ, n <= z -> A n. +Theorem strong_left_induction: left_step' -> forall n, n <= z -> A n. Proof. -intro LS'; apply NZA'A_left; unfold A'; NZinduct n (S z); -[apply NZlbase | apply NZls'_ls''; apply LS']. +intro LS'; apply A'A_left; unfold A'; nzinduct n (S z); +[apply lbase | apply ls'_ls''; apply LS']. Qed. -Theorem NZleft_induction : A z -> left_step -> forall n : NZ, n <= z -> A n. +Theorem left_induction : A z -> left_step -> forall n, n <= z -> A n. Proof. -intros Az LS; apply NZstrong_left_induction; now apply NZls_ls'. +intros Az LS; apply strong_left_induction; now apply ls_ls'. Qed. -Theorem NZleft_induction' : - (forall n : NZ, z <= n -> A n) -> left_step -> forall n : NZ, A n. +Theorem left_induction' : + (forall n, z <= n -> A n) -> left_step -> forall n, A n. Proof. intros R L n. -destruct (NZlt_trichotomy n z) as [H | [H | H]]. -apply NZleft_induction. apply R. now apply NZeq_le_incl. assumption. now apply NZlt_le_incl. -rewrite H; apply R; now apply NZeq_le_incl. -apply R; now apply NZlt_le_incl. +destruct (lt_trichotomy n z) as [H | [H | H]]. +apply left_induction. apply R. now apply eq_le_incl. assumption. +now apply lt_le_incl. +rewrite H; apply R; now apply eq_le_incl. +apply R; now apply lt_le_incl. Qed. -Theorem NZstrong_left_induction' : - (forall n : NZ, z <= n -> A n) -> left_step' -> forall n : NZ, A n. +Theorem strong_left_induction' : + (forall n, z <= n -> A n) -> left_step' -> forall n, A n. Proof. intros R L n. -destruct (NZlt_trichotomy n z) as [H | [H | H]]. -apply NZstrong_left_induction; auto. now apply NZlt_le_incl. -rewrite H; apply R; now apply NZeq_le_incl. -apply R; now apply NZlt_le_incl. +destruct (lt_trichotomy n z) as [H | [H | H]]. +apply strong_left_induction; auto. now apply lt_le_incl. +rewrite H; apply R; now apply eq_le_incl. +apply R; now apply lt_le_incl. Qed. End LeftInduction. -Theorem NZorder_induction : +Theorem order_induction : A z -> - (forall n : NZ, z <= n -> A n -> A (S n)) -> - (forall n : NZ, n < z -> A (S n) -> A n) -> - forall n : NZ, A n. + (forall n, z <= n -> A n -> A (S n)) -> + (forall n, n < z -> A (S n) -> A n) -> + forall n, A n. Proof. intros Az RS LS n. -destruct (NZlt_trichotomy n z) as [H | [H | H]]. -now apply NZleft_induction; [| | apply NZlt_le_incl]. +destruct (lt_trichotomy n z) as [H | [H | H]]. +now apply left_induction; [| | apply lt_le_incl]. now rewrite H. -now apply NZright_induction; [| | apply NZlt_le_incl]. +now apply right_induction; [| | apply lt_le_incl]. Qed. -Theorem NZorder_induction' : +Theorem order_induction' : A z -> - (forall n : NZ, z <= n -> A n -> A (S n)) -> - (forall n : NZ, n <= z -> A n -> A (P n)) -> - forall n : NZ, A n. + (forall n, z <= n -> A n -> A (S n)) -> + (forall n, n <= z -> A n -> A (P n)) -> + forall n, A n. Proof. -intros Az AS AP n; apply NZorder_induction; try assumption. -intros m H1 H2. apply AP in H2; [| now apply <- NZle_succ_l]. -apply -> (A_wd (P (S m)) m); [assumption | apply NZpred_succ]. +intros Az AS AP n; apply order_induction; try assumption. +intros m H1 H2. apply AP in H2; [| now apply <- le_succ_l]. +apply -> (A_wd (P (S m)) m); [assumption | apply pred_succ]. Qed. End Center. -Theorem NZorder_induction_0 : +Theorem order_induction_0 : A 0 -> - (forall n : NZ, 0 <= n -> A n -> A (S n)) -> - (forall n : NZ, n < 0 -> A (S n) -> A n) -> - forall n : NZ, A n. -Proof (NZorder_induction 0). + (forall n, 0 <= n -> A n -> A (S n)) -> + (forall n, n < 0 -> A (S n) -> A n) -> + forall n, A n. +Proof (order_induction 0). -Theorem NZorder_induction'_0 : +Theorem order_induction'_0 : A 0 -> - (forall n : NZ, 0 <= n -> A n -> A (S n)) -> - (forall n : NZ, n <= 0 -> A n -> A (P n)) -> - forall n : NZ, A n. -Proof (NZorder_induction' 0). + (forall n, 0 <= n -> A n -> A (S n)) -> + (forall n, n <= 0 -> A n -> A (P n)) -> + forall n, A n. +Proof (order_induction' 0). (** Elimintation principle for < *) -Theorem NZlt_ind : forall (n : NZ), +Theorem lt_ind : forall (n : t), A (S n) -> - (forall m : NZ, n < m -> A m -> A (S m)) -> - forall m : NZ, n < m -> A m. + (forall m, n < m -> A m -> A (S m)) -> + forall m, n < m -> A m. Proof. intros n H1 H2 m H3. -apply NZright_induction with (S n); [assumption | | now apply <- NZle_succ_l]. -intros; apply H2; try assumption. now apply -> NZle_succ_l. +apply right_induction with (S n); [assumption | | now apply <- le_succ_l]. +intros; apply H2; try assumption. now apply -> le_succ_l. Qed. (** Elimintation principle for <= *) -Theorem NZle_ind : forall (n : NZ), +Theorem le_ind : forall (n : t), A n -> - (forall m : NZ, n <= m -> A m -> A (S m)) -> - forall m : NZ, n <= m -> A m. + (forall m, n <= m -> A m -> A (S m)) -> + forall m, n <= m -> A m. Proof. intros n H1 H2 m H3. -now apply NZright_induction with n. +now apply right_induction with n. Qed. End Induction. -Tactic Notation "NZord_induct" ident(n) := - induction_maker n ltac:(apply NZorder_induction_0). +Tactic Notation "nzord_induct" ident(n) := + induction_maker n ltac:(apply order_induction_0). -Tactic Notation "NZord_induct" ident(n) constr(z) := - induction_maker n ltac:(apply NZorder_induction with z). +Tactic Notation "nzord_induct" ident(n) constr(z) := + induction_maker n ltac:(apply order_induction with z). Section WF. -Variable z : NZ. +Variable z : t. -Let Rlt (n m : NZ) := z <= n /\ n < m. -Let Rgt (n m : NZ) := m < n /\ n <= z. +Let Rlt (n m : t) := z <= n /\ n < m. +Let Rgt (n m : t) := m < n /\ n <= z. -Instance Rlt_wd : Proper (NZeq ==> NZeq ==> iff) Rlt. +Instance Rlt_wd : Proper (eq ==> eq ==> iff) Rlt. Proof. intros x1 x2 H1 x3 x4 H2; unfold Rlt. rewrite H1; now rewrite H2. Qed. -Instance Rgt_wd : Proper (NZeq ==> NZeq ==> iff) Rgt. +Instance Rgt_wd : Proper (eq ==> eq ==> iff) Rgt. Proof. intros x1 x2 H1 x3 x4 H2; unfold Rgt; rewrite H1; now rewrite H2. Qed. -Instance NZAcc_lt_wd : Proper (NZeq==>iff) (Acc Rlt). +Instance Acc_lt_wd : Proper (eq==>iff) (Acc Rlt). Proof. intros x1 x2 H; split; intro H1; destruct H1 as [H2]; constructor; intros; apply H2; now (rewrite H || rewrite <- H). Qed. -Instance NZAcc_gt_wd : Proper (NZeq==>iff) (Acc Rgt). +Instance Acc_gt_wd : Proper (eq==>iff) (Acc Rgt). Proof. intros x1 x2 H; split; intro H1; destruct H1 as [H2]; constructor; intros; apply H2; now (rewrite H || rewrite <- H). Qed. -Theorem NZlt_wf : well_founded Rlt. +Theorem lt_wf : well_founded Rlt. Proof. unfold well_founded. -apply NZstrong_right_induction' with (z := z). -apply NZAcc_lt_wd. +apply strong_right_induction' with (z := z). +apply Acc_lt_wd. intros n H; constructor; intros y [H1 H2]. -apply <- NZnle_gt in H2. elim H2. now apply NZle_trans with z. +apply <- nle_gt in H2. elim H2. now apply le_trans with z. intros n H1 H2; constructor; intros m [H3 H4]. now apply H2. Qed. -Theorem NZgt_wf : well_founded Rgt. +Theorem gt_wf : well_founded Rgt. Proof. unfold well_founded. -apply NZstrong_left_induction' with (z := z). -apply NZAcc_gt_wd. +apply strong_left_induction' with (z := z). +apply Acc_gt_wd. intros n H; constructor; intros y [H1 H2]. -apply <- NZnle_gt in H2. elim H2. now apply NZle_lt_trans with n. +apply <- nle_gt in H2. elim H2. now apply le_lt_trans with n. intros n H1 H2; constructor; intros m [H3 H4]. -apply H2. assumption. now apply <- NZle_succ_l. +apply H2. assumption. now apply <- le_succ_l. Qed. End WF. +(** * Compatibility of [min] and [max]. *) + +Instance min_wd : Proper (eq==>eq==>eq) min. +Proof. +intros n n' Hn m m' Hm. +destruct (le_ge_cases n m). +rewrite 2 min_l; auto. now rewrite <-Hn,<-Hm. +rewrite 2 min_r; auto. now rewrite <-Hn,<-Hm. +Qed. + +Instance max_wd : Proper (eq==>eq==>eq) max. +Proof. +intros n n' Hn m m' Hm. +destruct (le_ge_cases n m). +rewrite 2 max_r; auto. now rewrite <-Hn,<-Hm. +rewrite 2 max_l; auto. now rewrite <-Hn,<-Hm. +Qed. + End NZOrderPropFunct. diff --git a/theories/Numbers/NatInt/NZProperties.v b/theories/Numbers/NatInt/NZProperties.v new file mode 100644 index 000000000..781d06594 --- /dev/null +++ b/theories/Numbers/NatInt/NZProperties.v @@ -0,0 +1,20 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) +(* \VV/ **************************************************************) +(* // * This file is distributed under the terms of the *) +(* * GNU Lesser General Public License Version 2.1 *) +(************************************************************************) +(* Evgeny Makarov, INRIA, 2007 *) +(************************************************************************) + +(*i $Id$ i*) + +Require Export NZAxioms NZMulOrder. + +(** This functor summarizes all known facts about NZ. + For the moment it is only an alias to [NZMulOrderPropFunct], which + subsumes all others. +*) + +Module NZPropFunct := NZMulOrderPropFunct. diff --git a/theories/Numbers/Natural/Abstract/NAdd.v b/theories/Numbers/Natural/Abstract/NAdd.v index 58dddfcf9..c3e1e223e 100644 --- a/theories/Numbers/Natural/Abstract/NAdd.v +++ b/theories/Numbers/Natural/Abstract/NAdd.v @@ -12,70 +12,28 @@ Require Export NBase. -Module NAddPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NBasePropMod := NBasePropFunct NAxiomsMod. +Module NAddPropFunct (Import N : NAxiomsSig). +Include NBasePropFunct N. -Open Local Scope NatScope. +Local Open Scope NumScope. -Theorem add_wd : - forall n1 n2 : N, n1 == n2 -> forall m1 m2 : N, m1 == m2 -> n1 + m1 == n2 + m2. -Proof NZadd_wd. +(** For theorems about [add] that are both valid for [N] and [Z], see [NZAdd] *) +(** Now comes theorems valid for natural numbers but not for Z *) -Theorem add_0_l : forall n : N, 0 + n == n. -Proof NZadd_0_l. - -Theorem add_succ_l : forall n m : N, (S n) + m == S (n + m). -Proof NZadd_succ_l. - -(** Theorems that are valid for both natural numbers and integers *) - -Theorem add_0_r : forall n : N, n + 0 == n. -Proof NZadd_0_r. - -Theorem add_succ_r : forall n m : N, n + S m == S (n + m). -Proof NZadd_succ_r. - -Theorem add_comm : forall n m : N, n + m == m + n. -Proof NZadd_comm. - -Theorem add_assoc : forall n m p : N, n + (m + p) == (n + m) + p. -Proof NZadd_assoc. - -Theorem add_shuffle1 : forall n m p q : N, (n + m) + (p + q) == (n + p) + (m + q). -Proof NZadd_shuffle1. - -Theorem add_shuffle2 : forall n m p q : N, (n + m) + (p + q) == (n + q) + (m + p). -Proof NZadd_shuffle2. - -Theorem add_1_l : forall n : N, 1 + n == S n. -Proof NZadd_1_l. - -Theorem add_1_r : forall n : N, n + 1 == S n. -Proof NZadd_1_r. - -Theorem add_cancel_l : forall n m p : N, p + n == p + m <-> n == m. -Proof NZadd_cancel_l. - -Theorem add_cancel_r : forall n m p : N, n + p == m + p <-> n == m. -Proof NZadd_cancel_r. - -(* Theorems that are valid for natural numbers but cannot be proved for Z *) - -Theorem eq_add_0 : forall n m : N, n + m == 0 <-> n == 0 /\ m == 0. +Theorem eq_add_0 : forall n m, n + m == 0 <-> n == 0 /\ m == 0. Proof. intros n m; induct n. -(* The next command does not work with the axiom add_0_l from NAddSig *) -rewrite add_0_l. intuition reflexivity. -intros n IH. rewrite add_succ_l. -setoid_replace (S (n + m) == 0) with False using relation iff by +nzsimpl; intuition. +intros n IH. nzsimpl. +setoid_replace (S (n + m) == 0) with False by (apply -> neg_false; apply neq_succ_0). -setoid_replace (S n == 0) with False using relation iff by +setoid_replace (S n == 0) with False by (apply -> neg_false; apply neq_succ_0). tauto. Qed. Theorem eq_add_succ : - forall n m : N, (exists p : N, n + m == S p) <-> - (exists n' : N, n == S n') \/ (exists m' : N, m == S m'). + forall n m, (exists p, n + m == S p) <-> + (exists n', n == S n') \/ (exists m', m == S m'). Proof. intros n m; cases n. split; intro H. @@ -88,11 +46,11 @@ left; now exists n. exists (n + m); now rewrite add_succ_l. Qed. -Theorem eq_add_1 : forall n m : N, +Theorem eq_add_1 : forall n m, n + m == 1 -> n == 1 /\ m == 0 \/ n == 0 /\ m == 1. Proof. intros n m H. -assert (H1 : exists p : N, n + m == S p) by now exists 0. +assert (H1 : exists p, n + m == S p) by now exists 0. apply -> eq_add_succ in H1. destruct H1 as [[n' H1] | [m' H1]]. left. rewrite H1 in H; rewrite add_succ_l in H; apply succ_inj in H. apply -> eq_add_0 in H. destruct H as [H2 H3]; rewrite H2 in H1; now split. @@ -100,7 +58,7 @@ right. rewrite H1 in H; rewrite add_succ_r in H; apply succ_inj in H. apply -> eq_add_0 in H. destruct H as [H2 H3]; rewrite H3 in H1; now split. Qed. -Theorem succ_add_discr : forall n m : N, m ~= S (n + m). +Theorem succ_add_discr : forall n m, m ~= S (n + m). Proof. intro n; induct m. apply neq_sym. apply neq_succ_0. @@ -108,49 +66,18 @@ intros m IH H. apply succ_inj in H. rewrite add_succ_r in H. unfold not in IH; now apply IH. Qed. -Theorem add_pred_l : forall n m : N, n ~= 0 -> P n + m == P (n + m). +Theorem add_pred_l : forall n m, n ~= 0 -> P n + m == P (n + m). Proof. intros n m; cases n. intro H; now elim H. intros n IH; rewrite add_succ_l; now do 2 rewrite pred_succ. Qed. -Theorem add_pred_r : forall n m : N, m ~= 0 -> n + P m == P (n + m). +Theorem add_pred_r : forall n m, m ~= 0 -> n + P m == P (n + m). Proof. intros n m H; rewrite (add_comm n (P m)); rewrite (add_comm n m); now apply add_pred_l. Qed. -(* One could define n <= m as exists p : N, p + n == m. Then we have -dichotomy: - -forall n m : N, n <= m \/ m <= n, - -i.e., - -forall n m : N, (exists p : N, p + n == m) \/ (exists p : N, p + m == n) (1) - -We will need (1) in the proof of induction principle for integers -constructed as pairs of natural numbers. The formula (1) can be proved -using properties of order and truncated subtraction. Thus, p would be -m - n or n - m and (1) would hold by theorem sub_add from Sub.v -depending on whether n <= m or m <= n. However, in proving induction -for integers constructed from natural numbers we do not need to -require implementations of order and sub; it is enough to prove (1) -here. *) - -Theorem add_dichotomy : - forall n m : N, (exists p : N, p + n == m) \/ (exists p : N, p + m == n). -Proof. -intros n m; induct n. -left; exists m; apply add_0_r. -intros n IH. -destruct IH as [[p H] | [p H]]. -destruct (zero_or_succ p) as [H1 | [p' H1]]; rewrite H1 in H. -rewrite add_0_l in H. right; exists (S 0); rewrite H; rewrite add_succ_l; now rewrite add_0_l. -left; exists p'; rewrite add_succ_r; now rewrite add_succ_l in H. -right; exists (S p). rewrite add_succ_l; now rewrite H. -Qed. - End NAddPropFunct. diff --git a/theories/Numbers/Natural/Abstract/NAddOrder.v b/theories/Numbers/Natural/Abstract/NAddOrder.v index 59f1c9347..f48b62e61 100644 --- a/theories/Numbers/Natural/Abstract/NAddOrder.v +++ b/theories/Numbers/Natural/Abstract/NAddOrder.v @@ -12,103 +12,38 @@ Require Export NOrder. -Module NAddOrderPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NOrderPropMod := NOrderPropFunct NAxiomsMod. -Open Local Scope NatScope. +Module NAddOrderPropFunct (Import N : NAxiomsSig). +Include NOrderPropFunct N. +Local Open Scope NumScope. -Theorem add_lt_mono_l : forall n m p : N, n < m <-> p + n < p + m. -Proof NZadd_lt_mono_l. +(** Theorems true for natural numbers, not for integers *) -Theorem add_lt_mono_r : forall n m p : N, n < m <-> n + p < m + p. -Proof NZadd_lt_mono_r. - -Theorem add_lt_mono : forall n m p q : N, n < m -> p < q -> n + p < m + q. -Proof NZadd_lt_mono. - -Theorem add_le_mono_l : forall n m p : N, n <= m <-> p + n <= p + m. -Proof NZadd_le_mono_l. - -Theorem add_le_mono_r : forall n m p : N, n <= m <-> n + p <= m + p. -Proof NZadd_le_mono_r. - -Theorem add_le_mono : forall n m p q : N, n <= m -> p <= q -> n + p <= m + q. -Proof NZadd_le_mono. - -Theorem add_lt_le_mono : forall n m p q : N, n < m -> p <= q -> n + p < m + q. -Proof NZadd_lt_le_mono. - -Theorem add_le_lt_mono : forall n m p q : N, n <= m -> p < q -> n + p < m + q. -Proof NZadd_le_lt_mono. - -Theorem add_pos_pos : forall n m : N, 0 < n -> 0 < m -> 0 < n + m. -Proof NZadd_pos_pos. - -Theorem lt_add_pos_l : forall n m : N, 0 < n -> m < n + m. -Proof NZlt_add_pos_l. - -Theorem lt_add_pos_r : forall n m : N, 0 < n -> m < m + n. -Proof NZlt_add_pos_r. - -Theorem le_lt_add_lt : forall n m p q : N, n <= m -> p + m < q + n -> p < q. -Proof NZle_lt_add_lt. - -Theorem lt_le_add_lt : forall n m p q : N, n < m -> p + m <= q + n -> p < q. -Proof NZlt_le_add_lt. - -Theorem le_le_add_le : forall n m p q : N, n <= m -> p + m <= q + n -> p <= q. -Proof NZle_le_add_le. - -Theorem add_lt_cases : forall n m p q : N, n + m < p + q -> n < p \/ m < q. -Proof NZadd_lt_cases. - -Theorem add_le_cases : forall n m p q : N, n + m <= p + q -> n <= p \/ m <= q. -Proof NZadd_le_cases. - -Theorem add_pos_cases : forall n m : N, 0 < n + m -> 0 < n \/ 0 < m. -Proof NZadd_pos_cases. - -(* Theorems true for natural numbers *) - -Theorem le_add_r : forall n m : N, n <= n + m. +Theorem le_add_r : forall n m, n <= n + m. Proof. intro n; induct m. rewrite add_0_r; now apply eq_le_incl. intros m IH. rewrite add_succ_r; now apply le_le_succ_r. Qed. -Theorem lt_lt_add_r : forall n m p : N, n < m -> n < m + p. +Theorem lt_lt_add_r : forall n m p, n < m -> n < m + p. Proof. intros n m p H; rewrite <- (add_0_r n). apply add_lt_le_mono; [assumption | apply le_0_l]. Qed. -Theorem lt_lt_add_l : forall n m p : N, n < m -> n < p + m. +Theorem lt_lt_add_l : forall n m p, n < m -> n < p + m. Proof. intros n m p; rewrite add_comm; apply lt_lt_add_r. Qed. -Theorem add_pos_l : forall n m : N, 0 < n -> 0 < n + m. +Theorem add_pos_l : forall n m, 0 < n -> 0 < n + m. Proof. -intros; apply NZadd_pos_nonneg. assumption. apply le_0_l. +intros; apply add_pos_nonneg. assumption. apply le_0_l. Qed. -Theorem add_pos_r : forall n m : N, 0 < m -> 0 < n + m. -Proof. -intros; apply NZadd_nonneg_pos. apply le_0_l. assumption. -Qed. - -(* The following property is used to prove the correctness of the -definition of order on integers constructed from pairs of natural numbers *) - -Theorem add_lt_repl_pair : forall n m n' m' u v : N, - n + u < m + v -> n + m' == n' + m -> n' + u < m' + v. +Theorem add_pos_r : forall n m, 0 < m -> 0 < n + m. Proof. -intros n m n' m' u v H1 H2. -symmetry in H2. assert (H3 : n' + m <= n + m') by now apply eq_le_incl. -pose proof (add_lt_le_mono _ _ _ _ H1 H3) as H4. -rewrite (add_shuffle2 n u), (add_shuffle1 m v), (add_comm m n) in H4. -do 2 rewrite <- add_assoc in H4. do 2 apply <- add_lt_mono_l in H4. -now rewrite (add_comm n' u), (add_comm m' v). +intros; apply add_nonneg_pos. apply le_0_l. assumption. Qed. End NAddOrderPropFunct. diff --git a/theories/Numbers/Natural/Abstract/NAxioms.v b/theories/Numbers/Natural/Abstract/NAxioms.v index 6a34d0f7b..bdabb1086 100644 --- a/theories/Numbers/Natural/Abstract/NAxioms.v +++ b/theories/Numbers/Natural/Abstract/NAxioms.v @@ -15,54 +15,24 @@ Require Export NZAxioms. Set Implicit Arguments. Module Type NAxiomsSig. -Declare Module Export NZOrdAxiomsMod : NZOrdAxiomsSig. +Include Type NZOrdAxiomsSig. +Local Open Scope NumScope. -Delimit Scope NatScope with Nat. -Notation N := NZ. -Notation Neq := NZeq. -Notation N0 := NZ0. -Notation N1 := (NZsucc NZ0). -Notation S := NZsucc. -Notation P := NZpred. -Notation add := NZadd. -Notation mul := NZmul. -Notation sub := NZsub. -Notation lt := NZlt. -Notation le := NZle. -Notation min := NZmin. -Notation max := NZmax. -Notation "x == y" := (Neq x y) (at level 70) : NatScope. -Notation "x ~= y" := (~ Neq x y) (at level 70) : NatScope. -Notation "0" := NZ0 : NatScope. -Notation "1" := (NZsucc NZ0) : NatScope. -Notation "x + y" := (NZadd x y) : NatScope. -Notation "x - y" := (NZsub x y) : NatScope. -Notation "x * y" := (NZmul x y) : NatScope. -Notation "x < y" := (NZlt x y) : NatScope. -Notation "x <= y" := (NZle x y) : NatScope. -Notation "x > y" := (NZlt y x) (only parsing) : NatScope. -Notation "x >= y" := (NZle y x) (only parsing) : NatScope. - -Open Local Scope NatScope. +Axiom pred_0 : P 0 == 0. -Parameter Inline recursion : forall A : Type, A -> (N -> A -> A) -> N -> A. +Parameter Inline recursion : forall A : Type, A -> (t -> A -> A) -> t -> A. Implicit Arguments recursion [A]. -Axiom pred_0 : P 0 == 0. - Instance recursion_wd (A : Type) (Aeq : relation A) : - Proper (Aeq ==> (Neq==>Aeq==>Aeq) ==> Neq ==> Aeq) (@recursion A). + Proper (Aeq ==> (eq==>Aeq==>Aeq) ==> eq ==> Aeq) (@recursion A). Axiom recursion_0 : - forall (A : Type) (a : A) (f : N -> A -> A), recursion a f 0 = a. + forall (A : Type) (a : A) (f : t -> A -> A), recursion a f 0 = a. Axiom recursion_succ : - forall (A : Type) (Aeq : relation A) (a : A) (f : N -> A -> A), - Aeq a a -> Proper (Neq==>Aeq==>Aeq) f -> - forall n : N, Aeq (recursion a f (S n)) (f n (recursion a f n)). - -(*Axiom dep_rec : - forall A : N -> Type, A 0 -> (forall n : N, A n -> A (S n)) -> forall n : N, A n.*) + forall (A : Type) (Aeq : relation A) (a : A) (f : t -> A -> A), + Aeq a a -> Proper (eq==>Aeq==>Aeq) f -> + forall n, Aeq (recursion a f (S n)) (f n (recursion a f n)). End NAxiomsSig. diff --git a/theories/Numbers/Natural/Abstract/NBase.v b/theories/Numbers/Natural/Abstract/NBase.v index 02d82bacd..6bf12ee5e 100644 --- a/theories/Numbers/Natural/Abstract/NBase.v +++ b/theories/Numbers/Natural/Abstract/NBase.v @@ -12,131 +12,75 @@ Require Export Decidable. Require Export NAxioms. -Require Import NZMulOrder. (* The last property functor on NZ, which subsumes all others *) +Require Import NZProperties. -Module NBasePropFunct (Import NAxiomsMod : NAxiomsSig). +Module NBasePropFunct (Import N : NAxiomsSig). +(** First, we import all known facts about both natural numbers and integers. *) +Include NZPropFunct N. +Local Open Scope NumScope. -Open Local Scope NatScope. - -(* We call the last property functor on NZ, which includes all the previous -ones, to get all properties of NZ at once. This way we will include them -only one time. *) - -Module Export NZMulOrderMod := NZMulOrderPropFunct NZOrdAxiomsMod. - -(* Here we probably need to re-prove all axioms declared in NAxioms.v to -make sure that the definitions like N, S and add are unfolded in them, -since unfolding is done only inside a functor. In fact, we'll do it in the -files that prove the corresponding properties. In those files, we will also -rename properties proved in NZ files by removing NZ from their names. In -this way, one only has to consult, for example, NAdd.v to see all -available properties for add, i.e., one does not have to go to NAxioms.v -for axioms and NZAdd.v for theorems. *) - -Theorem succ_wd : forall n1 n2 : N, n1 == n2 -> S n1 == S n2. -Proof NZsucc_wd. - -Theorem pred_wd : forall n1 n2 : N, n1 == n2 -> P n1 == P n2. -Proof NZpred_wd. - -Theorem pred_succ : forall n : N, P (S n) == n. -Proof NZpred_succ. - -Theorem pred_0 : P 0 == 0. -Proof pred_0. - -Theorem Neq_refl : forall n : N, n == n. -Proof (@Equivalence_Reflexive _ _ NZeq_equiv). - -Theorem Neq_sym : forall n m : N, n == m -> m == n. -Proof (@Equivalence_Symmetric _ _ NZeq_equiv). - -Theorem Neq_trans : forall n m p : N, n == m -> m == p -> n == p. -Proof (@Equivalence_Transitive _ _ NZeq_equiv). - -Theorem neq_sym : forall n m : N, n ~= m -> m ~= n. -Proof NZneq_sym. - -Theorem succ_inj : forall n1 n2 : N, S n1 == S n2 -> n1 == n2. -Proof NZsucc_inj. - -Theorem succ_inj_wd : forall n1 n2 : N, S n1 == S n2 <-> n1 == n2. -Proof NZsucc_inj_wd. - -Theorem succ_inj_wd_neg : forall n m : N, S n ~= S m <-> n ~= m. -Proof NZsucc_inj_wd_neg. - -(* Decidability and stability of equality was proved only in NZOrder, but -since it does not mention order, we'll put it here *) - -Theorem eq_dec : forall n m : N, decidable (n == m). -Proof NZeq_dec. - -Theorem eq_dne : forall n m : N, ~ ~ n == m <-> n == m. -Proof NZeq_dne. - -(* Now we prove that the successor of a number is not zero by defining a +(** We prove that the successor of a number is not zero by defining a function (by recursion) that maps 0 to false and the successor to true *) -Definition if_zero (A : Set) (a b : A) (n : N) : A := +Definition if_zero (A : Type) (a b : A) (n : N.t) : A := recursion a (fun _ _ => b) n. -Instance if_zero_wd (A : Set) : Proper (eq ==> eq ==> Neq ==> eq) (if_zero A). +Implicit Arguments if_zero [A]. + +Instance if_zero_wd (A : Type) : + Proper (Logic.eq ==> Logic.eq ==> N.eq ==> Logic.eq) (@if_zero A). Proof. intros; unfold if_zero. repeat red; intros. apply recursion_wd; auto. repeat red; auto. Qed. -Theorem if_zero_0 : forall (A : Set) (a b : A), if_zero A a b 0 = a. +Theorem if_zero_0 : forall (A : Type) (a b : A), if_zero a b 0 = a. Proof. unfold if_zero; intros; now rewrite recursion_0. Qed. -Theorem if_zero_succ : forall (A : Set) (a b : A) (n : N), if_zero A a b (S n) = b. +Theorem if_zero_succ : + forall (A : Type) (a b : A) (n : N.t), if_zero a b (S n) = b. Proof. intros; unfold if_zero. -now rewrite (@recursion_succ A (@eq A)). +now rewrite recursion_succ. Qed. -Implicit Arguments if_zero [A]. - -Theorem neq_succ_0 : forall n : N, S n ~= 0. +Theorem neq_succ_0 : forall n, S n ~= 0. Proof. intros n H. -assert (true = false); [| discriminate]. -replace true with (if_zero false true (S n)) by apply if_zero_succ. -pattern false at 2; replace false with (if_zero false true 0) by apply if_zero_0. -now rewrite H. +generalize (Logic.eq_refl (if_zero false true 0)). +rewrite <- H at 1. rewrite if_zero_0, if_zero_succ; discriminate. Qed. -Theorem neq_0_succ : forall n : N, 0 ~= S n. +Theorem neq_0_succ : forall n, 0 ~= S n. Proof. intro n; apply neq_sym; apply neq_succ_0. Qed. -(* Next, we show that all numbers are nonnegative and recover regular induction -from the bidirectional induction on NZ *) +(** Next, we show that all numbers are nonnegative and recover regular + induction from the bidirectional induction on NZ *) -Theorem le_0_l : forall n : N, 0 <= n. +Theorem le_0_l : forall n, 0 <= n. Proof. -NZinduct n. -now apply NZeq_le_incl. +nzinduct n. +now apply eq_le_incl. intro n; split. -apply NZle_le_succ_r. -intro H; apply -> NZle_succ_r in H; destruct H as [H | H]. +apply le_le_succ_r. +intro H; apply -> le_succ_r in H; destruct H as [H | H]. assumption. symmetry in H; false_hyp H neq_succ_0. Qed. Theorem induction : - forall A : N -> Prop, Proper (Neq==>iff) A -> - A 0 -> (forall n : N, A n -> A (S n)) -> forall n : N, A n. + forall A : N.t -> Prop, Proper (N.eq==>iff) A -> + A 0 -> (forall n, A n -> A (S n)) -> forall n, A n. Proof. -intros A A_wd A0 AS n; apply NZright_induction with 0; try assumption. +intros A A_wd A0 AS n; apply right_induction with 0; try assumption. intros; auto; apply le_0_l. apply le_0_l. Qed. -(* The theorems NZinduction, NZcentral_induction and the tactic NZinduct +(** The theorems [bi_induction], [central_induction] and the tactic [nzinduct] refer to bidirectional induction, which is not useful on natural numbers. Therefore, we define a new induction tactic for natural numbers. We do not have to call "Declare Left Step" and "Declare Right Step" @@ -146,8 +90,8 @@ from NZ. *) Ltac induct n := induction_maker n ltac:(apply induction). Theorem case_analysis : - forall A : N -> Prop, Proper (Neq==>iff) A -> - A 0 -> (forall n : N, A (S n)) -> forall n : N, A n. + forall A : N.t -> Prop, Proper (N.eq==>iff) A -> + A 0 -> (forall n, A (S n)) -> forall n, A n. Proof. intros; apply induction; auto. Qed. @@ -173,7 +117,7 @@ now left. intro n; right; now exists n. Qed. -Theorem eq_pred_0 : forall n : N, P n == 0 <-> n == 0 \/ n == 1. +Theorem eq_pred_0 : forall n, P n == 0 <-> n == 0 \/ n == 1. Proof. cases n. rewrite pred_0. setoid_replace (0 == 1) with False using relation iff. tauto. @@ -184,14 +128,14 @@ setoid_replace (S n == 0) with False using relation iff by rewrite succ_inj_wd. tauto. Qed. -Theorem succ_pred : forall n : N, n ~= 0 -> S (P n) == n. +Theorem succ_pred : forall n, n ~= 0 -> S (P n) == n. Proof. cases n. intro H; exfalso; now apply H. intros; now rewrite pred_succ. Qed. -Theorem pred_inj : forall n m : N, n ~= 0 -> m ~= 0 -> P n == P m -> n == m. +Theorem pred_inj : forall n m, n ~= 0 -> m ~= 0 -> P n == P m -> n == m. Proof. intros n m; cases n. intros H; exfalso; now apply H. @@ -200,13 +144,13 @@ intros H; exfalso; now apply H. intros m H2 H3. do 2 rewrite pred_succ in H3. now rewrite H3. Qed. -(* The following induction principle is useful for reasoning about, e.g., +(** The following induction principle is useful for reasoning about, e.g., Fibonacci numbers *) Section PairInduction. -Variable A : N -> Prop. -Hypothesis A_wd : Proper (Neq==>iff) A. +Variable A : N.t -> Prop. +Hypothesis A_wd : Proper (N.eq==>iff) A. Theorem pair_induction : A 0 -> A 1 -> @@ -219,13 +163,12 @@ Qed. End PairInduction. -(*Ltac pair_induct n := induction_maker n ltac:(apply pair_induction).*) +(** The following is useful for reasoning about, e.g., Ackermann function *) -(* The following is useful for reasoning about, e.g., Ackermann function *) Section TwoDimensionalInduction. -Variable R : N -> N -> Prop. -Hypothesis R_wd : Proper (Neq==>Neq==>iff) R. +Variable R : N.t -> N.t -> Prop. +Hypothesis R_wd : Proper (N.eq==>N.eq==>iff) R. Theorem two_dim_induction : R 0 0 -> @@ -241,21 +184,16 @@ Qed. End TwoDimensionalInduction. -(*Ltac two_dim_induct n m := - try intros until n; - try intros until m; - pattern n, m; apply two_dim_induction; clear n m; - [solve_relation_wd | | | ].*) Section DoubleInduction. -Variable R : N -> N -> Prop. -Hypothesis R_wd : Proper (Neq==>Neq==>iff) R. +Variable R : N.t -> N.t -> Prop. +Hypothesis R_wd : Proper (N.eq==>N.eq==>iff) R. Theorem double_induction : - (forall m : N, R 0 m) -> - (forall n : N, R (S n) 0) -> - (forall n m : N, R n m -> R (S n) (S m)) -> forall n m : N, R n m. + (forall m, R 0 m) -> + (forall n, R (S n) 0) -> + (forall n m, R n m -> R (S n) (S m)) -> forall n m, R n m. Proof. intros H1 H2 H3; induct n; auto. intros n H; cases m; auto. diff --git a/theories/Numbers/Natural/Abstract/NDefOps.v b/theories/Numbers/Natural/Abstract/NDefOps.v index e864b66d5..123917375 100644 --- a/theories/Numbers/Natural/Abstract/NDefOps.v +++ b/theories/Numbers/Natural/Abstract/NDefOps.v @@ -13,48 +13,42 @@ Require Import Bool. (* To get the orb and negb function *) Require Export NStrongRec. -Module NdefOpsPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NStrongRecPropMod := NStrongRecPropFunct NAxiomsMod. -Local Open Scope NatScope. - -Hint Rewrite - add_0_l add_0_r add_succ_l add_succ_r - mul_0_l mul_0_r mul_succ_l mul_succ_l : numbers. - -Ltac nsimpl := autorewrite with numbers. +Module NdefOpsPropFunct (Import N : NAxiomsSig). +Include NStrongRecPropFunct N. +Local Open Scope NumScope. (*****************************************************) (** Addition *) -Definition def_add (x y : N) := recursion y (fun _ => S) x. +Definition def_add (x y : N.t) := recursion y (fun _ => S) x. Local Infix "+++" := def_add (at level 50, left associativity). -Instance def_add_prewd : Proper (Neq==>Neq==>Neq) (fun _ => S). +Instance def_add_prewd : Proper (N.eq==>N.eq==>N.eq) (fun _ => S). Proof. intros _ _ _ p p' Epp'; now rewrite Epp'. Qed. -Instance def_add_wd : Proper (Neq ==> Neq ==> Neq) def_add. +Instance def_add_wd : Proper (N.eq ==> N.eq ==> N.eq) def_add. Proof. intros x x' Exx' y y' Eyy'. unfold def_add. (* TODO: why rewrite Exx' don't work here (or verrrry slowly) ? *) -apply recursion_wd with (Aeq := Neq); auto with *. +apply recursion_wd with (Aeq := N.eq); auto with *. apply def_add_prewd. Qed. -Theorem def_add_0_l : forall y : N, 0 +++ y == y. +Theorem def_add_0_l : forall y, 0 +++ y == y. Proof. intro y. unfold def_add. now rewrite recursion_0. Qed. -Theorem def_add_succ_l : forall x y : N, S x +++ y == S (x +++ y). +Theorem def_add_succ_l : forall x y, S x +++ y == S (x +++ y). Proof. intros x y; unfold def_add. rewrite recursion_succ; auto with *. Qed. -Theorem def_add_add : forall n m : N, n +++ m == n + m. +Theorem def_add_add : forall n m, n +++ m == n + m. Proof. intros n m; induct n. now rewrite def_add_0_l, add_0_l. @@ -64,17 +58,17 @@ Qed. (*****************************************************) (** Multiplication *) -Definition def_mul (x y : N) := recursion 0 (fun _ p => p +++ x) y. +Definition def_mul (x y : N.t) := recursion 0 (fun _ p => p +++ x) y. Local Infix "**" := def_mul (at level 40, left associativity). Instance def_mul_prewd : - Proper (Neq==>Neq==>Neq==>Neq) (fun x _ p => p +++ x). + Proper (N.eq==>N.eq==>N.eq==>N.eq) (fun x _ p => p +++ x). Proof. repeat red; intros; now apply def_add_wd. Qed. -Instance def_mul_wd : Proper (Neq ==> Neq ==> Neq) def_mul. +Instance def_mul_wd : Proper (N.eq ==> N.eq ==> N.eq) def_mul. Proof. unfold def_mul. intros x x' Exx' y y' Eyy'. @@ -82,19 +76,19 @@ apply recursion_wd; auto with *. now apply def_mul_prewd. Qed. -Theorem def_mul_0_r : forall x : N, x ** 0 == 0. +Theorem def_mul_0_r : forall x, x ** 0 == 0. Proof. intro. unfold def_mul. now rewrite recursion_0. Qed. -Theorem def_mul_succ_r : forall x y : N, x ** S y == x ** y +++ x. +Theorem def_mul_succ_r : forall x y, x ** S y == x ** y +++ x. Proof. intros x y; unfold def_mul. rewrite recursion_succ; auto with *. now apply def_mul_prewd. Qed. -Theorem def_mul_mul : forall n m : N, n ** m == n * m. +Theorem def_mul_mul : forall n m, n ** m == n * m. Proof. intros n m; induct m. now rewrite def_mul_0_r, mul_0_r. @@ -104,7 +98,7 @@ Qed. (*****************************************************) (** Order *) -Definition ltb (m : N) : N -> bool := +Definition ltb (m : N.t) : N.t -> bool := recursion (if_zero false true) (fun _ f n => recursion false (fun n' _ => f n') n) @@ -112,12 +106,12 @@ recursion Local Infix "<<" := ltb (at level 70, no associativity). -Instance ltb_prewd1 : Proper (Neq==>eq) (if_zero false true). +Instance ltb_prewd1 : Proper (N.eq==>Logic.eq) (if_zero false true). Proof. red; intros; apply if_zero_wd; auto. Qed. -Instance ltb_prewd2 : Proper (Neq==>(Neq==>eq)==>Neq==>eq) +Instance ltb_prewd2 : Proper (N.eq==>(N.eq==>Logic.eq)==>N.eq==>Logic.eq) (fun _ f n => recursion false (fun n' _ => f n') n). Proof. repeat red; intros; simpl. @@ -125,7 +119,7 @@ apply recursion_wd; auto with *. repeat red; auto. Qed. -Instance ltb_wd : Proper (Neq ==> Neq ==> eq) ltb. +Instance ltb_wd : Proper (N.eq ==> N.eq ==> Logic.eq) ltb. Proof. unfold ltb. intros n n' Hn m m' Hm. @@ -133,13 +127,13 @@ apply f_equiv; auto with *. apply recursion_wd; auto; [ apply ltb_prewd1 | apply ltb_prewd2 ]. Qed. -Theorem ltb_base : forall n : N, 0 << n = if_zero false true n. +Theorem ltb_base : forall n, 0 << n = if_zero false true n. Proof. intro n; unfold ltb; now rewrite recursion_0. Qed. Theorem ltb_step : - forall m n : N, S m << n = recursion false (fun n' _ => m << n') n. + forall m n, S m << n = recursion false (fun n' _ => m << n') n. Proof. intros m n; unfold ltb at 1. apply f_equiv; auto with *. @@ -153,26 +147,26 @@ Qed. functions themselves, i.e., rewrite (recursion lt_base lt_step (S n)) to lt_step n (recursion lt_base lt_step n)? *) -Theorem ltb_0 : forall n : N, n << 0 = false. +Theorem ltb_0 : forall n, n << 0 = false. Proof. cases n. rewrite ltb_base; now rewrite if_zero_0. intro n; rewrite ltb_step. now rewrite recursion_0. Qed. -Theorem ltb_0_succ : forall n : N, 0 << S n = true. +Theorem ltb_0_succ : forall n, 0 << S n = true. Proof. intro n; rewrite ltb_base; now rewrite if_zero_succ. Qed. -Theorem succ_ltb_mono : forall n m : N, (S n << S m) = (n << m). +Theorem succ_ltb_mono : forall n m, (S n << S m) = (n << m). Proof. intros n m. rewrite ltb_step. rewrite recursion_succ; try reflexivity. repeat red; intros; now apply ltb_wd. Qed. -Theorem ltb_lt : forall n m : N, n << m = true <-> n < m. +Theorem ltb_lt : forall n m, n << m = true <-> n < m. Proof. double_induct n m. cases m. @@ -186,9 +180,9 @@ Qed. (*****************************************************) (** Even *) -Definition even (x : N) := recursion true (fun _ p => negb p) x. +Definition even (x : N.t) := recursion true (fun _ p => negb p) x. -Instance even_wd : Proper (Neq==>eq) even. +Instance even_wd : Proper (N.eq==>Logic.eq) even. Proof. intros n n' Hn. unfold even. apply recursion_wd; auto. @@ -201,7 +195,7 @@ unfold even. now rewrite recursion_0. Qed. -Theorem even_succ : forall x : N, even (S x) = negb (even x). +Theorem even_succ : forall x, even (S x) = negb (even x). Proof. unfold even. intro x; rewrite recursion_succ; try reflexivity. @@ -217,12 +211,12 @@ Local Notation "a < b <= c" := (a<b /\ b<=c). Local Notation "a < b < c" := (a<b /\ b<c). Local Notation "2" := (S 1). -Definition half_aux (x : N) : N * N := +Definition half_aux (x : N.t) : N.t * N.t := recursion (0, 0) (fun _ p => let (x1, x2) := p in (S x2, x1)) x. -Definition half (x : N) := snd (half_aux x). +Definition half (x : N.t) := snd (half_aux x). -Instance half_aux_wd : Proper (Neq ==> Neq*Neq) half_aux. +Instance half_aux_wd : Proper (N.eq ==> N.eq*N.eq) half_aux. Proof. intros x x' Hx. unfold half_aux. apply recursion_wd; auto with *. @@ -230,7 +224,7 @@ intros y y' Hy (u,v) (u',v') (Hu,Hv). compute in *. rewrite Hu, Hv; auto with *. Qed. -Instance half_wd : Proper (Neq==>Neq) half. +Instance half_wd : Proper (N.eq==>N.eq) half. Proof. intros x x' Hx. unfold half. rewrite Hx; auto with *. Qed. @@ -290,7 +284,7 @@ Theorem half_double : forall n, n == 2 * half n \/ n == 1 + 2 * half n. Proof. intros. unfold half. -nsimpl. +nzsimpl. destruct (half_aux_spec2 n) as [H|H]; [left|right]. rewrite <- H at 1. apply half_aux_spec. rewrite <- add_succ_l. rewrite <- H at 1. apply half_aux_spec. @@ -301,7 +295,7 @@ Proof. intros. destruct (half_double n) as [E|E]; rewrite E at 2. apply le_refl. -nsimpl. +nzsimpl. apply le_le_succ_r, le_refl. Qed. @@ -309,7 +303,7 @@ Theorem half_lower_bound : forall n, n <= 1 + 2 * half n. Proof. intros. destruct (half_double n) as [E|E]; rewrite E at 1. -nsimpl. +nzsimpl. apply le_le_succ_r, le_refl. apply le_refl. Qed. @@ -345,17 +339,17 @@ Qed. (*****************************************************) (** Power *) -Definition pow (n m : N) := recursion 1 (fun _ r => n*r) m. +Definition pow (n m : N.t) := recursion 1 (fun _ r => n*r) m. Local Infix "^^" := pow (at level 30, right associativity). Instance pow_prewd : - Proper (Neq==>Neq==>Neq==>Neq) (fun n _ r => n*r). + Proper (N.eq==>N.eq==>N.eq==>N.eq) (fun n _ r => n*r). Proof. intros n n' Hn x x' Hx y y' Hy. rewrite Hn, Hy; auto with *. Qed. -Instance pow_wd : Proper (Neq==>Neq==>Neq) pow. +Instance pow_wd : Proper (N.eq==>N.eq==>N.eq) pow. Proof. intros n n' Hn m m' Hm. unfold pow. apply recursion_wd; auto with *. @@ -377,7 +371,7 @@ Qed. (*****************************************************) (** Logarithm for the base 2 *) -Definition log (x : N) : N := +Definition log (x : N.t) : N.t := strong_rec 0 (fun g x => if x << 2 then 0 @@ -385,7 +379,7 @@ strong_rec 0 x. Instance log_prewd : - Proper ((Neq==>Neq)==>Neq==>Neq) + Proper ((N.eq==>N.eq)==>N.eq==>N.eq) (fun g x => if x<<2 then 0 else S (g (half x))). Proof. intros g g' Hg n n' Hn. @@ -395,7 +389,7 @@ apply succ_wd. apply Hg. rewrite Hn; auto with *. Qed. -Instance log_wd : Proper (Neq==>Neq) log. +Instance log_wd : Proper (N.eq==>N.eq) log. Proof. intros x x' Exx'. unfold log. apply strong_rec_wd; auto with *. @@ -403,7 +397,7 @@ apply log_prewd. Qed. Lemma log_good_step : forall n h1 h2, - (forall m : N, m < n -> h1 m == h2 m) -> + (forall m, m < n -> h1 m == h2 m) -> (if n << 2 then 0 else S (h1 (half n))) == (if n << 2 then 0 else S (h2 (half n))). Proof. @@ -460,10 +454,10 @@ split. rewrite <- le_succ_l in IH1. apply mul_le_mono_l with (p:=2) in IH1. eapply lt_le_trans; eauto. -nsimpl. +nzsimpl. rewrite lt_succ_r. eapply le_trans; [ eapply half_lower_bound | ]. -nsimpl; apply le_refl. +nzsimpl; apply le_refl. eapply le_trans; [ | eapply half_upper_bound ]. apply mul_le_mono_l; auto. Qed. diff --git a/theories/Numbers/Natural/Abstract/NIso.v b/theories/Numbers/Natural/Abstract/NIso.v index 6ecf7fd33..13e289c29 100644 --- a/theories/Numbers/Natural/Abstract/NIso.v +++ b/theories/Numbers/Natural/Abstract/NIso.v @@ -12,47 +12,37 @@ Require Import NBase. -Module Homomorphism (NAxiomsMod1 NAxiomsMod2 : NAxiomsSig). +Module Homomorphism (N1 N2 : NAxiomsSig). -Module NBasePropMod2 := NBasePropFunct NAxiomsMod2. +Local Notation "n == m" := (N2.eq n m) (at level 70, no associativity). -Notation Local N1 := NAxiomsMod1.N. -Notation Local N2 := NAxiomsMod2.N. -Notation Local Eq1 := NAxiomsMod1.Neq. -Notation Local Eq2 := NAxiomsMod2.Neq. -Notation Local O1 := NAxiomsMod1.N0. -Notation Local O2 := NAxiomsMod2.N0. -Notation Local S1 := NAxiomsMod1.S. -Notation Local S2 := NAxiomsMod2.S. -Notation Local "n == m" := (Eq2 n m) (at level 70, no associativity). +Definition homomorphism (f : N1.t -> N2.t) : Prop := + f N1.zero == N2.zero /\ forall n, f (N1.S n) == N2.S (f n). -Definition homomorphism (f : N1 -> N2) : Prop := - f O1 == O2 /\ forall n : N1, f (S1 n) == S2 (f n). +Definition natural_isomorphism : N1.t -> N2.t := + N1.recursion N2.zero (fun (n : N1.t) (p : N2.t) => N2.S p). -Definition natural_isomorphism : N1 -> N2 := - NAxiomsMod1.recursion O2 (fun (n : N1) (p : N2) => S2 p). - -Instance natural_isomorphism_wd : Proper (Eq1 ==> Eq2) natural_isomorphism. +Instance natural_isomorphism_wd : Proper (N1.eq ==> N2.eq) natural_isomorphism. Proof. unfold natural_isomorphism. intros n m Eqxy. -apply NAxiomsMod1.recursion_wd with (Aeq := Eq2). +apply N1.recursion_wd. reflexivity. -intros _ _ _ y' y'' H. now apply NBasePropMod2.succ_wd. +intros _ _ _ y' y'' H. now apply N2.succ_wd. assumption. Qed. -Theorem natural_isomorphism_0 : natural_isomorphism O1 == O2. +Theorem natural_isomorphism_0 : natural_isomorphism N1.zero == N2.zero. Proof. -unfold natural_isomorphism; now rewrite NAxiomsMod1.recursion_0. +unfold natural_isomorphism; now rewrite N1.recursion_0. Qed. Theorem natural_isomorphism_succ : - forall n : N1, natural_isomorphism (S1 n) == S2 (natural_isomorphism n). + forall n : N1.t, natural_isomorphism (N1.S n) == N2.S (natural_isomorphism n). Proof. unfold natural_isomorphism. -intro n. rewrite (@NAxiomsMod1.recursion_succ N2 NAxiomsMod2.Neq); auto with *. -repeat red; intros. apply NBasePropMod2.succ_wd; auto. +intro n. rewrite N1.recursion_succ; auto with *. +repeat red; intros. apply N2.succ_wd; auto. Qed. Theorem hom_nat_iso : homomorphism natural_isomorphism. @@ -63,23 +53,20 @@ Qed. End Homomorphism. -Module Inverse (NAxiomsMod1 NAxiomsMod2 : NAxiomsSig). +Module Inverse (N1 N2 : NAxiomsSig). -Module Import NBasePropMod1 := NBasePropFunct NAxiomsMod1. +Module Import NBasePropMod1 := NBasePropFunct N1. (* This makes the tactic induct available. Since it is taken from (NBasePropFunct NAxiomsMod1), it refers to induction on N1. *) -Module Hom12 := Homomorphism NAxiomsMod1 NAxiomsMod2. -Module Hom21 := Homomorphism NAxiomsMod2 NAxiomsMod1. - -Notation Local N1 := NAxiomsMod1.N. -Notation Local N2 := NAxiomsMod2.N. -Notation Local h12 := Hom12.natural_isomorphism. -Notation Local h21 := Hom21.natural_isomorphism. +Module Hom12 := Homomorphism N1 N2. +Module Hom21 := Homomorphism N2 N1. -Notation Local "n == m" := (NAxiomsMod1.Neq n m) (at level 70, no associativity). +Local Notation h12 := Hom12.natural_isomorphism. +Local Notation h21 := Hom21.natural_isomorphism. +Local Notation "n == m" := (N1.eq n m) (at level 70, no associativity). -Lemma inverse_nat_iso : forall n : N1, h21 (h12 n) == n. +Lemma inverse_nat_iso : forall n : N1.t, h21 (h12 n) == n. Proof. induct n. now rewrite Hom12.natural_isomorphism_0, Hom21.natural_isomorphism_0. @@ -89,25 +76,20 @@ Qed. End Inverse. -Module Isomorphism (NAxiomsMod1 NAxiomsMod2 : NAxiomsSig). - -Module Hom12 := Homomorphism NAxiomsMod1 NAxiomsMod2. -Module Hom21 := Homomorphism NAxiomsMod2 NAxiomsMod1. +Module Isomorphism (N1 N2 : NAxiomsSig). -Module Inverse12 := Inverse NAxiomsMod1 NAxiomsMod2. -Module Inverse21 := Inverse NAxiomsMod2 NAxiomsMod1. +Module Hom12 := Homomorphism N1 N2. +Module Hom21 := Homomorphism N2 N1. +Module Inverse12 := Inverse N1 N2. +Module Inverse21 := Inverse N2 N1. -Notation Local N1 := NAxiomsMod1.N. -Notation Local N2 := NAxiomsMod2.N. -Notation Local Eq1 := NAxiomsMod1.Neq. -Notation Local Eq2 := NAxiomsMod2.Neq. -Notation Local h12 := Hom12.natural_isomorphism. -Notation Local h21 := Hom21.natural_isomorphism. +Local Notation h12 := Hom12.natural_isomorphism. +Local Notation h21 := Hom21.natural_isomorphism. -Definition isomorphism (f1 : N1 -> N2) (f2 : N2 -> N1) : Prop := +Definition isomorphism (f1 : N1.t -> N2.t) (f2 : N2.t -> N1.t) : Prop := Hom12.homomorphism f1 /\ Hom21.homomorphism f2 /\ - forall n : N1, Eq1 (f2 (f1 n)) n /\ - forall n : N2, Eq2 (f1 (f2 n)) n. + forall n, N1.eq (f2 (f1 n)) n /\ + forall n, N2.eq (f1 (f2 n)) n. Theorem iso_nat_iso : isomorphism h12 h21. Proof. diff --git a/theories/Numbers/Natural/Abstract/NMul.v b/theories/Numbers/Natural/Abstract/NMul.v deleted file mode 100644 index 69b284fdc..000000000 --- a/theories/Numbers/Natural/Abstract/NMul.v +++ /dev/null @@ -1,87 +0,0 @@ -(************************************************************************) -(* v * The Coq Proof Assistant / The Coq Development Team *) -(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) -(* \VV/ **************************************************************) -(* // * This file is distributed under the terms of the *) -(* * GNU Lesser General Public License Version 2.1 *) -(************************************************************************) -(* Evgeny Makarov, INRIA, 2007 *) -(************************************************************************) - -(*i $Id$ i*) - -Require Export NAdd. - -Module NMulPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NAddPropMod := NAddPropFunct NAxiomsMod. -Open Local Scope NatScope. - -Theorem mul_wd : - forall n1 n2 : N, n1 == n2 -> forall m1 m2 : N, m1 == m2 -> n1 * m1 == n2 * m2. -Proof NZmul_wd. - -Theorem mul_0_l : forall n : N, 0 * n == 0. -Proof NZmul_0_l. - -Theorem mul_succ_l : forall n m : N, (S n) * m == n * m + m. -Proof NZmul_succ_l. - -(** Theorems that are valid for both natural numbers and integers *) - -Theorem mul_0_r : forall n, n * 0 == 0. -Proof NZmul_0_r. - -Theorem mul_succ_r : forall n m, n * (S m) == n * m + n. -Proof NZmul_succ_r. - -Theorem mul_comm : forall n m : N, n * m == m * n. -Proof NZmul_comm. - -Theorem mul_add_distr_r : forall n m p : N, (n + m) * p == n * p + m * p. -Proof NZmul_add_distr_r. - -Theorem mul_add_distr_l : forall n m p : N, n * (m + p) == n * m + n * p. -Proof NZmul_add_distr_l. - -Theorem mul_assoc : forall n m p : N, n * (m * p) == (n * m) * p. -Proof NZmul_assoc. - -Theorem mul_1_l : forall n : N, 1 * n == n. -Proof NZmul_1_l. - -Theorem mul_1_r : forall n : N, n * 1 == n. -Proof NZmul_1_r. - -(* Theorems that cannot be proved in NZMul *) - -(* In proving the correctness of the definition of multiplication on -integers constructed from pairs of natural numbers, we'll need the -following fact about natural numbers: - -a * n + u == a * m + v -> n + m' == n' + m -> a * n' + u = a * m' + v - -Here n + m' == n' + m expresses equality of integers (n, m) and (n', m'), -since a pair (a, b) of natural numbers represents the integer a - b. On -integers, the formula above could be proved by moving a * m to the left, -factoring out a and replacing n - m by n' - m'. However, the formula is -required in the process of constructing integers, so it has to be proved -for natural numbers, where terms cannot be moved from one side of an -equation to the other. The proof uses the cancellation laws add_cancel_l -and add_cancel_r. *) - -Theorem add_mul_repl_pair : forall a n m n' m' u v : N, - a * n + u == a * m + v -> n + m' == n' + m -> a * n' + u == a * m' + v. -Proof. -intros a n m n' m' u v H1 H2. -apply (@NZmul_wd a a) in H2; [| reflexivity]. -do 2 rewrite mul_add_distr_l in H2. symmetry in H2. -pose proof (NZadd_wd _ _ H1 _ _ H2) as H3. -rewrite (add_shuffle1 (a * m)), (add_comm (a * m) (a * n)) in H3. -do 2 rewrite <- add_assoc in H3. apply -> add_cancel_l in H3. -rewrite (add_assoc u), (add_comm (a * m)) in H3. -apply -> add_cancel_r in H3. -now rewrite (add_comm (a * n') u), (add_comm (a * m') v). -Qed. - -End NMulPropFunct. - diff --git a/theories/Numbers/Natural/Abstract/NMulOrder.v b/theories/Numbers/Natural/Abstract/NMulOrder.v index ac4cc5e9e..285d8c104 100644 --- a/theories/Numbers/Natural/Abstract/NMulOrder.v +++ b/theories/Numbers/Natural/Abstract/NMulOrder.v @@ -12,118 +12,68 @@ Require Export NAddOrder. -Module NMulOrderPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NAddOrderPropMod := NAddOrderPropFunct NAxiomsMod. -Open Local Scope NatScope. +Module NMulOrderPropFunct (Import N : NAxiomsSig). +Include NAddOrderPropFunct N. +Local Open Scope NumScope. -Theorem mul_lt_pred : - forall p q n m : N, S p == q -> (p * n < p * m <-> q * n + m < q * m + n). -Proof NZmul_lt_pred. +(** Theorems that are either not valid on Z or have different proofs + on N and Z *) -Theorem mul_lt_mono_pos_l : forall p n m : N, 0 < p -> (n < m <-> p * n < p * m). -Proof NZmul_lt_mono_pos_l. - -Theorem mul_lt_mono_pos_r : forall p n m : N, 0 < p -> (n < m <-> n * p < m * p). -Proof NZmul_lt_mono_pos_r. - -Theorem mul_cancel_l : forall n m p : N, p ~= 0 -> (p * n == p * m <-> n == m). -Proof NZmul_cancel_l. - -Theorem mul_cancel_r : forall n m p : N, p ~= 0 -> (n * p == m * p <-> n == m). -Proof NZmul_cancel_r. - -Theorem mul_id_l : forall n m : N, m ~= 0 -> (n * m == m <-> n == 1). -Proof NZmul_id_l. - -Theorem mul_id_r : forall n m : N, n ~= 0 -> (n * m == n <-> m == 1). -Proof NZmul_id_r. - -Theorem mul_le_mono_pos_l : forall n m p : N, 0 < p -> (n <= m <-> p * n <= p * m). -Proof NZmul_le_mono_pos_l. - -Theorem mul_le_mono_pos_r : forall n m p : N, 0 < p -> (n <= m <-> n * p <= m * p). -Proof NZmul_le_mono_pos_r. - -Theorem mul_pos_pos : forall n m : N, 0 < n -> 0 < m -> 0 < n * m. -Proof NZmul_pos_pos. - -Theorem lt_1_mul_pos : forall n m : N, 1 < n -> 0 < m -> 1 < n * m. -Proof NZlt_1_mul_pos. - -Theorem eq_mul_0 : forall n m : N, n * m == 0 <-> n == 0 \/ m == 0. -Proof NZeq_mul_0. - -Theorem neq_mul_0 : forall n m : N, n ~= 0 /\ m ~= 0 <-> n * m ~= 0. -Proof NZneq_mul_0. - -Theorem eq_square_0 : forall n : N, n * n == 0 <-> n == 0. -Proof NZeq_square_0. - -Theorem eq_mul_0_l : forall n m : N, n * m == 0 -> m ~= 0 -> n == 0. -Proof NZeq_mul_0_l. - -Theorem eq_mul_0_r : forall n m : N, n * m == 0 -> n ~= 0 -> m == 0. -Proof NZeq_mul_0_r. - -Theorem square_lt_mono : forall n m : N, n < m <-> n * n < m * m. +Theorem square_lt_mono : forall n m, n < m <-> n * n < m * m. Proof. intros n m; split; intro; -[apply NZsquare_lt_mono_nonneg | apply NZsquare_lt_simpl_nonneg]; +[apply square_lt_mono_nonneg | apply square_lt_simpl_nonneg]; try assumption; apply le_0_l. Qed. -Theorem square_le_mono : forall n m : N, n <= m <-> n * n <= m * m. +Theorem square_le_mono : forall n m, n <= m <-> n * n <= m * m. Proof. intros n m; split; intro; -[apply NZsquare_le_mono_nonneg | apply NZsquare_le_simpl_nonneg]; +[apply square_le_mono_nonneg | apply square_le_simpl_nonneg]; try assumption; apply le_0_l. Qed. -Theorem mul_2_mono_l : forall n m : N, n < m -> 1 + (1 + 1) * n < (1 + 1) * m. -Proof NZmul_2_mono_l. - -(* Theorems that are either not valid on Z or have different proofs on N and Z *) - -Theorem mul_le_mono_l : forall n m p : N, n <= m -> p * n <= p * m. +Theorem mul_le_mono_l : forall n m p, n <= m -> p * n <= p * m. Proof. -intros; apply NZmul_le_mono_nonneg_l. apply le_0_l. assumption. +intros; apply mul_le_mono_nonneg_l. apply le_0_l. assumption. Qed. -Theorem mul_le_mono_r : forall n m p : N, n <= m -> n * p <= m * p. +Theorem mul_le_mono_r : forall n m p, n <= m -> n * p <= m * p. Proof. -intros; apply NZmul_le_mono_nonneg_r. apply le_0_l. assumption. +intros; apply mul_le_mono_nonneg_r. apply le_0_l. assumption. Qed. -Theorem mul_lt_mono : forall n m p q : N, n < m -> p < q -> n * p < m * q. +Theorem mul_lt_mono : forall n m p q, n < m -> p < q -> n * p < m * q. Proof. -intros; apply NZmul_lt_mono_nonneg; try assumption; apply le_0_l. +intros; apply mul_lt_mono_nonneg; try assumption; apply le_0_l. Qed. -Theorem mul_le_mono : forall n m p q : N, n <= m -> p <= q -> n * p <= m * q. +Theorem mul_le_mono : forall n m p q, n <= m -> p <= q -> n * p <= m * q. Proof. -intros; apply NZmul_le_mono_nonneg; try assumption; apply le_0_l. +intros; apply mul_le_mono_nonneg; try assumption; apply le_0_l. Qed. -Theorem lt_0_mul : forall n m : N, n * m > 0 <-> n > 0 /\ m > 0. +Theorem lt_0_mul' : forall n m, n * m > 0 <-> n > 0 /\ m > 0. Proof. intros n m; split; [intro H | intros [H1 H2]]. -apply -> NZlt_0_mul in H. destruct H as [[H1 H2] | [H1 H2]]. now split. false_hyp H1 nlt_0_r. -now apply NZmul_pos_pos. +apply -> lt_0_mul in H. destruct H as [[H1 H2] | [H1 H2]]. now split. + false_hyp H1 nlt_0_r. +now apply mul_pos_pos. Qed. -Notation mul_pos := lt_0_mul (only parsing). +Notation mul_pos := lt_0_mul' (only parsing). -Theorem eq_mul_1 : forall n m : N, n * m == 1 <-> n == 1 /\ m == 1. +Theorem eq_mul_1 : forall n m, n * m == 1 <-> n == 1 /\ m == 1. Proof. intros n m. split; [| intros [H1 H2]; now rewrite H1, H2, mul_1_l]. -intro H; destruct (NZlt_trichotomy n 1) as [H1 | [H1 | H1]]. +intro H; destruct (lt_trichotomy n 1) as [H1 | [H1 | H1]]. apply -> lt_1_r in H1. rewrite H1, mul_0_l in H. false_hyp H neq_0_succ. rewrite H1, mul_1_l in H; now split. destruct (eq_0_gt_0_cases m) as [H2 | H2]. rewrite H2, mul_0_r in H; false_hyp H neq_0_succ. apply -> (mul_lt_mono_pos_r m) in H1; [| assumption]. rewrite mul_1_l in H1. -assert (H3 : 1 < n * m) by now apply (lt_1_l 0 m). +assert (H3 : 1 < n * m) by now apply (lt_1_l m). rewrite H in H3; false_hyp H3 lt_irrefl. Qed. diff --git a/theories/Numbers/Natural/Abstract/NOrder.v b/theories/Numbers/Natural/Abstract/NOrder.v index a5b496ba3..94c68a186 100644 --- a/theories/Numbers/Natural/Abstract/NOrder.v +++ b/theories/Numbers/Natural/Abstract/NOrder.v @@ -10,352 +10,61 @@ (*i $Id$ i*) -Require Export NMul. +Require Export NAdd. -Module NOrderPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NMulPropMod := NMulPropFunct NAxiomsMod. -Open Local Scope NatScope. +Module NOrderPropFunct (Import N : NAxiomsSig). +Include NAddPropFunct N. +Local Open Scope NumScope. -(* The tactics le_less, le_equal and le_elim are inherited from NZOrder.v *) - -(* Axioms *) - -Theorem lt_wd : - forall n1 n2 : N, n1 == n2 -> forall m1 m2 : N, m1 == m2 -> (n1 < m1 <-> n2 < m2). -Proof NZlt_wd. - -Theorem le_wd : - forall n1 n2 : N, n1 == n2 -> forall m1 m2 : N, m1 == m2 -> (n1 <= m1 <-> n2 <= m2). -Proof NZle_wd. - -Theorem min_wd : - forall n1 n2 : N, n1 == n2 -> forall m1 m2 : N, m1 == m2 -> min n1 m1 == min n2 m2. -Proof NZmin_wd. - -Theorem max_wd : - forall n1 n2 : N, n1 == n2 -> forall m1 m2 : N, m1 == m2 -> max n1 m1 == max n2 m2. -Proof NZmax_wd. - -Theorem lt_eq_cases : forall n m : N, n <= m <-> n < m \/ n == m. -Proof NZlt_eq_cases. - -Theorem lt_irrefl : forall n : N, ~ n < n. -Proof NZlt_irrefl. - -Theorem lt_succ_r : forall n m : N, n < S m <-> n <= m. -Proof NZlt_succ_r. - -Theorem min_l : forall n m : N, n <= m -> min n m == n. -Proof NZmin_l. - -Theorem min_r : forall n m : N, m <= n -> min n m == m. -Proof NZmin_r. - -Theorem max_l : forall n m : N, m <= n -> max n m == n. -Proof NZmax_l. - -Theorem max_r : forall n m : N, n <= m -> max n m == m. -Proof NZmax_r. - -(* Renaming theorems from NZOrder.v *) - -Theorem lt_le_incl : forall n m : N, n < m -> n <= m. -Proof NZlt_le_incl. - -Theorem eq_le_incl : forall n m : N, n == m -> n <= m. -Proof NZeq_le_incl. - -Theorem lt_neq : forall n m : N, n < m -> n ~= m. -Proof NZlt_neq. - -Theorem le_neq : forall n m : N, n < m <-> n <= m /\ n ~= m. -Proof NZle_neq. - -Theorem le_refl : forall n : N, n <= n. -Proof NZle_refl. - -Theorem lt_succ_diag_r : forall n : N, n < S n. -Proof NZlt_succ_diag_r. - -Theorem le_succ_diag_r : forall n : N, n <= S n. -Proof NZle_succ_diag_r. - -Theorem lt_0_1 : 0 < 1. -Proof NZlt_0_1. - -Theorem le_0_1 : 0 <= 1. -Proof NZle_0_1. - -Theorem lt_lt_succ_r : forall n m : N, n < m -> n < S m. -Proof NZlt_lt_succ_r. - -Theorem le_le_succ_r : forall n m : N, n <= m -> n <= S m. -Proof NZle_le_succ_r. - -Theorem le_succ_r : forall n m : N, n <= S m <-> n <= m \/ n == S m. -Proof NZle_succ_r. - -Theorem neq_succ_diag_l : forall n : N, S n ~= n. -Proof NZneq_succ_diag_l. - -Theorem neq_succ_diag_r : forall n : N, n ~= S n. -Proof NZneq_succ_diag_r. - -Theorem nlt_succ_diag_l : forall n : N, ~ S n < n. -Proof NZnlt_succ_diag_l. - -Theorem nle_succ_diag_l : forall n : N, ~ S n <= n. -Proof NZnle_succ_diag_l. - -Theorem le_succ_l : forall n m : N, S n <= m <-> n < m. -Proof NZle_succ_l. - -Theorem lt_succ_l : forall n m : N, S n < m -> n < m. -Proof NZlt_succ_l. - -Theorem succ_lt_mono : forall n m : N, n < m <-> S n < S m. -Proof NZsucc_lt_mono. - -Theorem succ_le_mono : forall n m : N, n <= m <-> S n <= S m. -Proof NZsucc_le_mono. - -Theorem lt_asymm : forall n m : N, n < m -> ~ m < n. -Proof NZlt_asymm. - -Notation lt_ngt := lt_asymm (only parsing). - -Theorem lt_trans : forall n m p : N, n < m -> m < p -> n < p. -Proof NZlt_trans. - -Theorem le_trans : forall n m p : N, n <= m -> m <= p -> n <= p. -Proof NZle_trans. - -Theorem le_lt_trans : forall n m p : N, n <= m -> m < p -> n < p. -Proof NZle_lt_trans. - -Theorem lt_le_trans : forall n m p : N, n < m -> m <= p -> n < p. -Proof NZlt_le_trans. - -Theorem le_antisymm : forall n m : N, n <= m -> m <= n -> n == m. -Proof NZle_antisymm. - -(** Trichotomy, decidability, and double negation elimination *) - -Theorem lt_trichotomy : forall n m : N, n < m \/ n == m \/ m < n. -Proof NZlt_trichotomy. - -Notation lt_eq_gt_cases := lt_trichotomy (only parsing). - -Theorem lt_gt_cases : forall n m : N, n ~= m <-> n < m \/ n > m. -Proof NZlt_gt_cases. - -Theorem le_gt_cases : forall n m : N, n <= m \/ n > m. -Proof NZle_gt_cases. - -Theorem lt_ge_cases : forall n m : N, n < m \/ n >= m. -Proof NZlt_ge_cases. - -Theorem le_ge_cases : forall n m : N, n <= m \/ n >= m. -Proof NZle_ge_cases. - -Theorem le_ngt : forall n m : N, n <= m <-> ~ n > m. -Proof NZle_ngt. - -Theorem nlt_ge : forall n m : N, ~ n < m <-> n >= m. -Proof NZnlt_ge. - -Theorem lt_dec : forall n m : N, decidable (n < m). -Proof NZlt_dec. - -Theorem lt_dne : forall n m : N, ~ ~ n < m <-> n < m. -Proof NZlt_dne. - -Theorem nle_gt : forall n m : N, ~ n <= m <-> n > m. -Proof NZnle_gt. - -Theorem lt_nge : forall n m : N, n < m <-> ~ n >= m. -Proof NZlt_nge. - -Theorem le_dec : forall n m : N, decidable (n <= m). -Proof NZle_dec. - -Theorem le_dne : forall n m : N, ~ ~ n <= m <-> n <= m. -Proof NZle_dne. - -Theorem nlt_succ_r : forall n m : N, ~ m < S n <-> n < m. -Proof NZnlt_succ_r. - -Theorem lt_exists_pred : - forall z n : N, z < n -> exists k : N, n == S k /\ z <= k. -Proof NZlt_exists_pred. - -Theorem lt_succ_iter_r : - forall (n : nat) (m : N), m < NZsucc_iter (Datatypes.S n) m. -Proof NZlt_succ_iter_r. - -Theorem neq_succ_iter_l : - forall (n : nat) (m : N), NZsucc_iter (Datatypes.S n) m ~= m. -Proof NZneq_succ_iter_l. - -(** Stronger variant of induction with assumptions n >= 0 (n < 0) -in the induction step *) - -Theorem right_induction : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, A z -> - (forall n : N, z <= n -> A n -> A (S n)) -> - forall n : N, z <= n -> A n. -Proof NZright_induction. - -Theorem left_induction : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, A z -> - (forall n : N, n < z -> A (S n) -> A n) -> - forall n : N, n <= z -> A n. -Proof NZleft_induction. - -Theorem right_induction' : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, - (forall n : N, n <= z -> A n) -> - (forall n : N, z <= n -> A n -> A (S n)) -> - forall n : N, A n. -Proof NZright_induction'. - -Theorem left_induction' : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, - (forall n : N, z <= n -> A n) -> - (forall n : N, n < z -> A (S n) -> A n) -> - forall n : N, A n. -Proof NZleft_induction'. - -Theorem strong_right_induction : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, - (forall n : N, z <= n -> (forall m : N, z <= m -> m < n -> A m) -> A n) -> - forall n : N, z <= n -> A n. -Proof NZstrong_right_induction. - -Theorem strong_left_induction : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, - (forall n : N, n <= z -> (forall m : N, m <= z -> S n <= m -> A m) -> A n) -> - forall n : N, n <= z -> A n. -Proof NZstrong_left_induction. - -Theorem strong_right_induction' : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, - (forall n : N, n <= z -> A n) -> - (forall n : N, z <= n -> (forall m : N, z <= m -> m < n -> A m) -> A n) -> - forall n : N, A n. -Proof NZstrong_right_induction'. - -Theorem strong_left_induction' : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, - (forall n : N, z <= n -> A n) -> - (forall n : N, n <= z -> (forall m : N, m <= z -> S n <= m -> A m) -> A n) -> - forall n : N, A n. -Proof NZstrong_left_induction'. - -Theorem order_induction : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, A z -> - (forall n : N, z <= n -> A n -> A (S n)) -> - (forall n : N, n < z -> A (S n) -> A n) -> - forall n : N, A n. -Proof NZorder_induction. - -Theorem order_induction' : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall z : N, A z -> - (forall n : N, z <= n -> A n -> A (S n)) -> - (forall n : N, n <= z -> A n -> A (P n)) -> - forall n : N, A n. -Proof NZorder_induction'. - -(* We don't need order_induction_0 and order_induction'_0 (see NZOrder and -ZOrder) since they boil down to regular induction *) - -(** Elimintation principle for < *) - -Theorem lt_ind : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall n : N, - A (S n) -> - (forall m : N, n < m -> A m -> A (S m)) -> - forall m : N, n < m -> A m. -Proof NZlt_ind. - -(** Elimintation principle for <= *) - -Theorem le_ind : - forall A : N -> Prop, Proper (Neq==>iff) A -> - forall n : N, - A n -> - (forall m : N, n <= m -> A m -> A (S m)) -> - forall m : N, n <= m -> A m. -Proof NZle_ind. - -(** Well-founded relations *) - -Theorem lt_wf : forall z : N, well_founded (fun n m : N => z <= n /\ n < m). -Proof NZlt_wf. - -Theorem gt_wf : forall z : N, well_founded (fun n m : N => m < n /\ n <= z). -Proof NZgt_wf. +(* Theorems that are true for natural numbers but not for integers *) Theorem lt_wf_0 : well_founded lt. Proof. -setoid_replace lt with (fun n m : N => 0 <= n /\ n < m). +setoid_replace lt with (fun n m => 0 <= n /\ n < m). apply lt_wf. intros x y; split. intro H; split; [apply le_0_l | assumption]. now intros [_ H]. Defined. -(* Theorems that are true for natural numbers but not for integers *) - (* "le_0_l : forall n : N, 0 <= n" was proved in NBase.v *) -Theorem nlt_0_r : forall n : N, ~ n < 0. +Theorem nlt_0_r : forall n, ~ n < 0. Proof. intro n; apply -> le_ngt. apply le_0_l. Qed. -Theorem nle_succ_0 : forall n : N, ~ (S n <= 0). +Theorem nle_succ_0 : forall n, ~ (S n <= 0). Proof. intros n H; apply -> le_succ_l in H; false_hyp H nlt_0_r. Qed. -Theorem le_0_r : forall n : N, n <= 0 <-> n == 0. +Theorem le_0_r : forall n, n <= 0 <-> n == 0. Proof. intros n; split; intro H. le_elim H; [false_hyp H nlt_0_r | assumption]. now apply eq_le_incl. Qed. -Theorem lt_0_succ : forall n : N, 0 < S n. +Theorem lt_0_succ : forall n, 0 < S n. Proof. induct n; [apply lt_succ_diag_r | intros n H; now apply lt_lt_succ_r]. Qed. -Theorem neq_0_lt_0 : forall n : N, n ~= 0 <-> 0 < n. +Theorem neq_0_lt_0 : forall n, n ~= 0 <-> 0 < n. Proof. cases n. split; intro H; [now elim H | intro; now apply lt_irrefl with 0]. intro n; split; intro H; [apply lt_0_succ | apply neq_succ_0]. Qed. -Theorem eq_0_gt_0_cases : forall n : N, n == 0 \/ 0 < n. +Theorem eq_0_gt_0_cases : forall n, n == 0 \/ 0 < n. Proof. cases n. now left. intro; right; apply lt_0_succ. Qed. -Theorem zero_one : forall n : N, n == 0 \/ n == 1 \/ 1 < n. +Theorem zero_one : forall n, n == 0 \/ n == 1 \/ 1 < n. Proof. induct n. now left. cases n. intros; right; now left. @@ -365,7 +74,7 @@ right; right. rewrite H. apply lt_succ_diag_r. right; right. now apply lt_lt_succ_r. Qed. -Theorem lt_1_r : forall n : N, n < 1 <-> n == 0. +Theorem lt_1_r : forall n, n < 1 <-> n == 0. Proof. cases n. split; intro; [reflexivity | apply lt_succ_diag_r]. @@ -373,7 +82,7 @@ intros n. rewrite <- succ_lt_mono. split; intro H; [false_hyp H nlt_0_r | false_hyp H neq_succ_0]. Qed. -Theorem le_1_r : forall n : N, n <= 1 <-> n == 0 \/ n == 1. +Theorem le_1_r : forall n, n <= 1 <-> n == 0 \/ n == 1. Proof. cases n. split; intro; [now left | apply le_succ_diag_r]. @@ -381,31 +90,30 @@ intro n. rewrite <- succ_le_mono, le_0_r, succ_inj_wd. split; [intro; now right | intros [H | H]; [false_hyp H neq_succ_0 | assumption]]. Qed. -Theorem lt_lt_0 : forall n m : N, n < m -> 0 < m. +Theorem lt_lt_0 : forall n m, n < m -> 0 < m. Proof. intros n m; induct n. trivial. intros n IH H. apply IH; now apply lt_succ_l. Qed. -Theorem lt_1_l : forall n m p : N, n < m -> m < p -> 1 < p. +Theorem lt_1_l' : forall n m p, n < m -> m < p -> 1 < p. Proof. -intros n m p H1 H2. -apply le_lt_trans with m. apply <- le_succ_l. apply le_lt_trans with n. -apply le_0_l. assumption. assumption. +intros. apply lt_1_l with m; auto. +apply le_lt_trans with n; auto. now apply le_0_l. Qed. (** Elimination principlies for < and <= for relations *) Section RelElim. -Variable R : relation N. -Hypothesis R_wd : Proper (Neq==>Neq==>iff) R. +Variable R : relation N.t. +Hypothesis R_wd : Proper (N.eq==>N.eq==>iff) R. Theorem le_ind_rel : - (forall m : N, R 0 m) -> - (forall n m : N, n <= m -> R n m -> R (S n) (S m)) -> - forall n m : N, n <= m -> R n m. + (forall m, R 0 m) -> + (forall n m, n <= m -> R n m -> R (S n) (S m)) -> + forall n m, n <= m -> R n m. Proof. intros Base Step; induct n. intros; apply Base. @@ -416,9 +124,9 @@ intros k H1 H2. apply -> le_succ_l in H1. apply lt_le_incl in H1. auto. Qed. Theorem lt_ind_rel : - (forall m : N, R 0 (S m)) -> - (forall n m : N, n < m -> R n m -> R (S n) (S m)) -> - forall n m : N, n < m -> R n m. + (forall m, R 0 (S m)) -> + (forall n m, n < m -> R n m -> R (S n) (S m)) -> + forall n m, n < m -> R n m. Proof. intros Base Step; induct n. intros m H. apply lt_exists_pred in H; destruct H as [m' [H _]]. @@ -433,61 +141,64 @@ End RelElim. (** Predecessor and order *) -Theorem succ_pred_pos : forall n : N, 0 < n -> S (P n) == n. +Theorem succ_pred_pos : forall n, 0 < n -> S (P n) == n. Proof. intros n H; apply succ_pred; intro H1; rewrite H1 in H. false_hyp H lt_irrefl. Qed. -Theorem le_pred_l : forall n : N, P n <= n. +Theorem le_pred_l : forall n, P n <= n. Proof. cases n. rewrite pred_0; now apply eq_le_incl. intros; rewrite pred_succ; apply le_succ_diag_r. Qed. -Theorem lt_pred_l : forall n : N, n ~= 0 -> P n < n. +Theorem lt_pred_l : forall n, n ~= 0 -> P n < n. Proof. cases n. intro H; exfalso; now apply H. intros; rewrite pred_succ; apply lt_succ_diag_r. Qed. -Theorem le_le_pred : forall n m : N, n <= m -> P n <= m. +Theorem le_le_pred : forall n m, n <= m -> P n <= m. Proof. intros n m H; apply le_trans with n. apply le_pred_l. assumption. Qed. -Theorem lt_lt_pred : forall n m : N, n < m -> P n < m. +Theorem lt_lt_pred : forall n m, n < m -> P n < m. Proof. intros n m H; apply le_lt_trans with n. apply le_pred_l. assumption. Qed. -Theorem lt_le_pred : forall n m : N, n < m -> n <= P m. (* Converse is false for n == m == 0 *) +Theorem lt_le_pred : forall n m, n < m -> n <= P m. + (* Converse is false for n == m == 0 *) Proof. intro n; cases m. intro H; false_hyp H nlt_0_r. intros m IH. rewrite pred_succ; now apply -> lt_succ_r. Qed. -Theorem lt_pred_le : forall n m : N, P n < m -> n <= m. (* Converse is false for n == m == 0 *) +Theorem lt_pred_le : forall n m, P n < m -> n <= m. + (* Converse is false for n == m == 0 *) Proof. intros n m; cases n. rewrite pred_0; intro H; now apply lt_le_incl. intros n IH. rewrite pred_succ in IH. now apply <- le_succ_l. Qed. -Theorem lt_pred_lt : forall n m : N, n < P m -> n < m. +Theorem lt_pred_lt : forall n m, n < P m -> n < m. Proof. intros n m H; apply lt_le_trans with (P m); [assumption | apply le_pred_l]. Qed. -Theorem le_pred_le : forall n m : N, n <= P m -> n <= m. +Theorem le_pred_le : forall n m, n <= P m -> n <= m. Proof. intros n m H; apply le_trans with (P m); [assumption | apply le_pred_l]. Qed. -Theorem pred_le_mono : forall n m : N, n <= m -> P n <= P m. (* Converse is false for n == 1, m == 0 *) +Theorem pred_le_mono : forall n m, n <= m -> P n <= P m. + (* Converse is false for n == 1, m == 0 *) Proof. intros n m H; elim H using le_ind_rel. solve_relation_wd. @@ -495,7 +206,7 @@ intro; rewrite pred_0; apply le_0_l. intros p q H1 _; now do 2 rewrite pred_succ. Qed. -Theorem pred_lt_mono : forall n m : N, n ~= 0 -> (n < m <-> P n < P m). +Theorem pred_lt_mono : forall n m, n ~= 0 -> (n < m <-> P n < P m). Proof. intros n m H1; split; intro H2. assert (m ~= 0). apply <- neq_0_lt_0. now apply lt_lt_0 with n. @@ -506,22 +217,24 @@ apply lt_le_trans with (P m). assumption. apply le_pred_l. apply -> succ_lt_mono in H2. now do 2 rewrite succ_pred in H2. Qed. -Theorem lt_succ_lt_pred : forall n m : N, S n < m <-> n < P m. +Theorem lt_succ_lt_pred : forall n m, S n < m <-> n < P m. Proof. intros n m. rewrite pred_lt_mono by apply neq_succ_0. now rewrite pred_succ. Qed. -Theorem le_succ_le_pred : forall n m : N, S n <= m -> n <= P m. (* Converse is false for n == m == 0 *) +Theorem le_succ_le_pred : forall n m, S n <= m -> n <= P m. + (* Converse is false for n == m == 0 *) Proof. intros n m H. apply lt_le_pred. now apply -> le_succ_l. Qed. -Theorem lt_pred_lt_succ : forall n m : N, P n < m -> n < S m. (* Converse is false for n == m == 0 *) +Theorem lt_pred_lt_succ : forall n m, P n < m -> n < S m. + (* Converse is false for n == m == 0 *) Proof. intros n m H. apply <- lt_succ_r. now apply lt_pred_le. Qed. -Theorem le_pred_le_succ : forall n m : N, P n <= m <-> n <= S m. +Theorem le_pred_le_succ : forall n m, P n <= m <-> n <= S m. Proof. intros n m; cases n. rewrite pred_0. split; intro H; apply le_0_l. diff --git a/theories/Numbers/Natural/Abstract/NProperties.v b/theories/Numbers/Natural/Abstract/NProperties.v new file mode 100644 index 000000000..29bda136a --- /dev/null +++ b/theories/Numbers/Natural/Abstract/NProperties.v @@ -0,0 +1,18 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) +(* \VV/ **************************************************************) +(* // * This file is distributed under the terms of the *) +(* * GNU Lesser General Public License Version 2.1 *) +(************************************************************************) + +(*i $Id$ i*) + +Require Export NAxioms NSub. + +(** This functor summarizes all known facts about N. + For the moment it is only an alias to [NSubPropFunct], which + subsumes all others. +*) + +Module NPropFunct := NSubPropFunct. diff --git a/theories/Numbers/Natural/Abstract/NStrongRec.v b/theories/Numbers/Natural/Abstract/NStrongRec.v index 1f5392f4a..fee9b4372 100644 --- a/theories/Numbers/Natural/Abstract/NStrongRec.v +++ b/theories/Numbers/Natural/Abstract/NStrongRec.v @@ -15,15 +15,15 @@ and proves its properties *) Require Export NSub. -Module NStrongRecPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NSubPropMod := NSubPropFunct NAxiomsMod. -Open Local Scope NatScope. +Module NStrongRecPropFunct (Import N : NAxiomsSig). +Include NSubPropFunct N. +Local Open Scope NumScope. Section StrongRecursion. Variable A : Type. Variable Aeq : relation A. -Context (Aeq_equiv : Equivalence Aeq). +Variable Aeq_equiv : Equivalence Aeq. (** [strong_rec] allows to define a recursive function [phi] given by an equation [phi(n) = F(phi)(n)] where recursive calls to [phi] @@ -37,13 +37,13 @@ Context (Aeq_equiv : Equivalence Aeq). that coincide with [phi] for numbers strictly less than [n]. *) -Definition strong_rec (a : A) (f : (N -> A) -> N -> A) (n : N) : A := +Definition strong_rec (a : A) (f : (N.t -> A) -> N.t -> A) (n : N.t) : A := recursion (fun _ => a) (fun _ => f) (S n) n. (** For convenience, we use in proofs an intermediate definition between [recursion] and [strong_rec]. *) -Definition strong_rec0 (a : A) (f : (N -> A) -> N -> A) : N -> N -> A := +Definition strong_rec0 (a : A) (f : (N.t -> A) -> N.t -> A) : N.t -> N.t -> A := recursion (fun _ => a) (fun _ => f). Lemma strong_rec_alt : forall a f n, @@ -54,13 +54,13 @@ Qed. (** We need a result similar to [f_equal], but for setoid equalities. *) Lemma f_equiv : forall f g x y, - (Neq==>Aeq)%signature f g -> Neq x y -> Aeq (f x) (g y). + (N.eq==>Aeq)%signature f g -> N.eq x y -> Aeq (f x) (g y). Proof. auto. Qed. Instance strong_rec0_wd : - Proper (Aeq ==> ((Neq ==> Aeq) ==> Neq ==> Aeq) ==> Neq ==> Neq ==> Aeq) + Proper (Aeq ==> ((N.eq ==> Aeq) ==> N.eq ==> Aeq) ==> N.eq ==> N.eq ==> Aeq) strong_rec0. Proof. unfold strong_rec0. @@ -70,7 +70,7 @@ apply recursion_wd; try red; auto. Qed. Instance strong_rec_wd : - Proper (Aeq ==> ((Neq ==> Aeq) ==> Neq ==> Aeq) ==> Neq ==> Aeq) strong_rec. + Proper (Aeq ==> ((N.eq ==> Aeq) ==> N.eq ==> Aeq) ==> N.eq ==> Aeq) strong_rec. Proof. intros a a' Eaa' f f' Eff' n n' Enn'. rewrite !strong_rec_alt. @@ -80,8 +80,8 @@ Qed. Section FixPoint. -Variable f : (N -> A) -> N -> A. -Context (f_wd : Proper ((Neq==>Aeq)==>Neq==>Aeq) f). +Variable f : (N.t -> A) -> N.t -> A. +Variable f_wd : Proper ((N.eq==>Aeq)==>N.eq==>Aeq) f. Lemma strong_rec0_0 : forall a m, (strong_rec0 a f 0 m) = a. @@ -112,8 +112,8 @@ calls h only on the segment [0 ... n - 1]. This means that if h1 and h2 coincide on values < n, then (f h1 n) coincides with (f h2 n) *) Hypothesis step_good : - forall (n : N) (h1 h2 : N -> A), - (forall m : N, m < n -> Aeq (h1 m) (h2 m)) -> Aeq (f h1 n) (f h2 n). + forall (n : N.t) (h1 h2 : N.t -> A), + (forall m : N.t, m < n -> Aeq (h1 m) (h2 m)) -> Aeq (f h1 n) (f h2 n). Lemma strong_rec0_more_steps : forall a k n m, m < n -> Aeq (strong_rec0 a f n m) (strong_rec0 a f (n+k) m). @@ -135,7 +135,7 @@ Proof. apply lt_le_trans with m; auto. Qed. -Lemma strong_rec0_fixpoint : forall (a : A) (n : N), +Lemma strong_rec0_fixpoint : forall (a : A) (n : N.t), Aeq (strong_rec0 a f (S n) n) (f (fun n => strong_rec0 a f (S n) n) n). Proof. intros. @@ -152,7 +152,7 @@ apply sub_add. rewrite le_succ_l; auto. Qed. -Theorem strong_rec_fixpoint : forall (a : A) (n : N), +Theorem strong_rec_fixpoint : forall (a : A) (n : N.t), Aeq (strong_rec a f n) (f (strong_rec a f) n). Proof. intros. @@ -168,7 +168,7 @@ Qed. that the first argument of [f] is arbitrary in this case... *) -Theorem strong_rec_0_any : forall (a : A)(any : N->A), +Theorem strong_rec_0_any : forall (a : A)(any : N.t->A), Aeq (strong_rec a f 0) (f any 0). Proof. intros. diff --git a/theories/Numbers/Natural/Abstract/NSub.v b/theories/Numbers/Natural/Abstract/NSub.v index cfeb6709b..62d1c731c 100644 --- a/theories/Numbers/Natural/Abstract/NSub.v +++ b/theories/Numbers/Natural/Abstract/NSub.v @@ -12,45 +12,30 @@ Require Export NMulOrder. -Module NSubPropFunct (Import NAxiomsMod : NAxiomsSig). -Module Export NMulOrderPropMod := NMulOrderPropFunct NAxiomsMod. -Open Local Scope NatScope. +Module NSubPropFunct (Import N : NAxiomsSig). +Include NMulOrderPropFunct N. +Local Open Scope NumScope. -Theorem sub_wd : - forall n1 n2 : N, n1 == n2 -> forall m1 m2 : N, m1 == m2 -> n1 - m1 == n2 - m2. -Proof NZsub_wd. - -Theorem sub_0_r : forall n : N, n - 0 == n. -Proof NZsub_0_r. - -Theorem sub_succ_r : forall n m : N, n - (S m) == P (n - m). -Proof NZsub_succ_r. - -Theorem sub_1_r : forall n : N, n - 1 == P n. -Proof. -intro n; rewrite sub_succ_r; now rewrite sub_0_r. -Qed. - -Theorem sub_0_l : forall n : N, 0 - n == 0. +Theorem sub_0_l : forall n, 0 - n == 0. Proof. induct n. apply sub_0_r. intros n IH; rewrite sub_succ_r; rewrite IH. now apply pred_0. Qed. -Theorem sub_succ : forall n m : N, S n - S m == n - m. +Theorem sub_succ : forall n m, S n - S m == n - m. Proof. intro n; induct m. rewrite sub_succ_r. do 2 rewrite sub_0_r. now rewrite pred_succ. intros m IH. rewrite sub_succ_r. rewrite IH. now rewrite sub_succ_r. Qed. -Theorem sub_diag : forall n : N, n - n == 0. +Theorem sub_diag : forall n, n - n == 0. Proof. induct n. apply sub_0_r. intros n IH; rewrite sub_succ; now rewrite IH. Qed. -Theorem sub_gt : forall n m : N, n > m -> n - m ~= 0. +Theorem sub_gt : forall n m, n > m -> n - m ~= 0. Proof. intros n m H; elim H using lt_ind_rel; clear n m H. solve_relation_wd. @@ -58,7 +43,7 @@ intro; rewrite sub_0_r; apply neq_succ_0. intros; now rewrite sub_succ. Qed. -Theorem add_sub_assoc : forall n m p : N, p <= m -> n + (m - p) == (n + m) - p. +Theorem add_sub_assoc : forall n m p, p <= m -> n + (m - p) == (n + m) - p. Proof. intros n m p; induct p. intro; now do 2 rewrite sub_0_r. @@ -68,32 +53,32 @@ rewrite add_pred_r by (apply sub_gt; now apply -> le_succ_l). reflexivity. Qed. -Theorem sub_succ_l : forall n m : N, n <= m -> S m - n == S (m - n). +Theorem sub_succ_l : forall n m, n <= m -> S m - n == S (m - n). Proof. intros n m H. rewrite <- (add_1_l m). rewrite <- (add_1_l (m - n)). symmetry; now apply add_sub_assoc. Qed. -Theorem add_sub : forall n m : N, (n + m) - m == n. +Theorem add_sub : forall n m, (n + m) - m == n. Proof. intros n m. rewrite <- add_sub_assoc by (apply le_refl). rewrite sub_diag; now rewrite add_0_r. Qed. -Theorem sub_add : forall n m : N, n <= m -> (m - n) + n == m. +Theorem sub_add : forall n m, n <= m -> (m - n) + n == m. Proof. intros n m H. rewrite add_comm. rewrite add_sub_assoc by assumption. rewrite add_comm. apply add_sub. Qed. -Theorem add_sub_eq_l : forall n m p : N, m + p == n -> n - m == p. +Theorem add_sub_eq_l : forall n m p, m + p == n -> n - m == p. Proof. intros n m p H. symmetry. assert (H1 : m + p - m == n - m) by now rewrite H. rewrite add_comm in H1. now rewrite add_sub in H1. Qed. -Theorem add_sub_eq_r : forall n m p : N, m + p == n -> n - p == m. +Theorem add_sub_eq_r : forall n m p, m + p == n -> n - p == m. Proof. intros n m p H; rewrite add_comm in H; now apply add_sub_eq_l. Qed. @@ -101,7 +86,7 @@ Qed. (* This could be proved by adding m to both sides. Then the proof would use add_sub_assoc and sub_0_le, which is proven below. *) -Theorem add_sub_eq_nz : forall n m p : N, p ~= 0 -> n - m == p -> m + p == n. +Theorem add_sub_eq_nz : forall n m p, p ~= 0 -> n - m == p -> m + p == n. Proof. intros n m p H; double_induct n m. intros m H1; rewrite sub_0_l in H1. symmetry in H1; false_hyp H1 H. @@ -110,14 +95,14 @@ intros n m IH H1. rewrite sub_succ in H1. apply IH in H1. rewrite add_succ_l; now rewrite H1. Qed. -Theorem sub_add_distr : forall n m p : N, n - (m + p) == (n - m) - p. +Theorem sub_add_distr : forall n m p, n - (m + p) == (n - m) - p. Proof. intros n m; induct p. rewrite add_0_r; now rewrite sub_0_r. intros p IH. rewrite add_succ_r; do 2 rewrite sub_succ_r. now rewrite IH. Qed. -Theorem add_sub_swap : forall n m p : N, p <= n -> n + m - p == n - p + m. +Theorem add_sub_swap : forall n m p, p <= n -> n + m - p == n - p + m. Proof. intros n m p H. rewrite (add_comm n m). @@ -127,7 +112,7 @@ Qed. (** Sub and order *) -Theorem le_sub_l : forall n m : N, n - m <= n. +Theorem le_sub_l : forall n m, n - m <= n. Proof. intro n; induct m. rewrite sub_0_r; now apply eq_le_incl. @@ -135,7 +120,7 @@ intros m IH. rewrite sub_succ_r. apply le_trans with (n - m); [apply le_pred_l | assumption]. Qed. -Theorem sub_0_le : forall n m : N, n - m == 0 <-> n <= m. +Theorem sub_0_le : forall n m, n - m == 0 <-> n <= m. Proof. double_induct n m. intro m; split; intro; [apply le_0_l | apply sub_0_l]. @@ -146,7 +131,7 @@ Qed. (** Sub and mul *) -Theorem mul_pred_r : forall n m : N, n * (P m) == n * m - n. +Theorem mul_pred_r : forall n m, n * (P m) == n * m - n. Proof. intros n m; cases m. now rewrite pred_0, mul_0_r, sub_0_l. @@ -155,7 +140,7 @@ now rewrite sub_diag, add_0_r. now apply eq_le_incl. Qed. -Theorem mul_sub_distr_r : forall n m p : N, (n - m) * p == n * p - m * p. +Theorem mul_sub_distr_r : forall n m p, (n - m) * p == n * p - m * p. Proof. intros n m p; induct n. now rewrite sub_0_l, mul_0_l, sub_0_l. @@ -170,11 +155,72 @@ setoid_replace ((S n * p) - m * p) with 0 by (apply <- sub_0_le; now apply mul_l apply mul_0_l. Qed. -Theorem mul_sub_distr_l : forall n m p : N, p * (n - m) == p * n - p * m. +Theorem mul_sub_distr_l : forall n m p, p * (n - m) == p * n - p * m. Proof. intros n m p; rewrite (mul_comm p (n - m)), (mul_comm p n), (mul_comm p m). apply mul_sub_distr_r. Qed. +(** Alternative definitions of [<=] and [<] based on [+] *) + +Definition le_alt n m := exists p, p + n == m. +Definition lt_alt n m := exists p, S p + n == m. + +Lemma le_equiv : forall n m, le_alt n m <-> n <= m. +Proof. +split. +intros (p,H). rewrite <- H, add_comm. apply le_add_r. +intro H. exists (m-n). now apply sub_add. +Qed. + +Lemma lt_equiv : forall n m, lt_alt n m <-> n < m. +Proof. +split. +intros (p,H). rewrite <- H, add_succ_l, lt_succ_r, add_comm. apply le_add_r. +intro H. exists (m-S n). rewrite add_succ_l, <- add_succ_r. +apply sub_add. now rewrite le_succ_l. +Qed. + +Instance le_alt_wd : Proper (eq==>eq==>iff) le_alt. +Proof. + intros x x' Hx y y' Hy; unfold le_alt. + setoid_rewrite Hx. setoid_rewrite Hy. auto with *. +Qed. + +Instance lt_alt_wd : Proper (eq==>eq==>iff) lt_alt. +Proof. + intros x x' Hx y y' Hy; unfold lt_alt. + setoid_rewrite Hx. setoid_rewrite Hy. auto with *. +Qed. + +(** With these alternative definition, the dichotomy: + +[forall n m, n <= m \/ m <= n] + +becomes: + +[forall n m, (exists p, p + n == m) \/ (exists p, p + m == n)] + +We will need this in the proof of induction principle for integers +constructed as pairs of natural numbers. This formula can be proved +from know properties of [<=]. However, it can also be done directly. *) + +Theorem le_alt_dichotomy : forall n m, le_alt n m \/ le_alt m n. +Proof. +intros n m; induct n. +left; exists m; apply add_0_r. +intros n IH. +destruct IH as [[p H] | [p H]]. +destruct (zero_or_succ p) as [H1 | [p' H1]]; rewrite H1 in H. +rewrite add_0_l in H. right; exists (S 0); rewrite H, add_succ_l; + now rewrite add_0_l. +left; exists p'; rewrite add_succ_r; now rewrite add_succ_l in H. +right; exists (S p). rewrite add_succ_l; now rewrite H. +Qed. + +Theorem add_dichotomy : + forall n m, (exists p, p + n == m) \/ (exists p, p + m == n). +Proof le_alt_dichotomy. + End NSubPropFunct. diff --git a/theories/Numbers/Natural/BigN/BigN.v b/theories/Numbers/Natural/BigN/BigN.v index 40f08356b..4cc867898 100644 --- a/theories/Numbers/Natural/BigN/BigN.v +++ b/theories/Numbers/Natural/BigN/BigN.v @@ -20,14 +20,14 @@ Require Import Cyclic31. Require Import NSig. Require Import NSigNAxioms. Require Import NMake. -Require Import NSub. +Require Import NProperties. Module BigN <: NType := NMake.Make Int31Cyclic. (** Module [BigN] implements [NAxiomsSig] *) Module Export BigNAxiomsMod := NSig_NAxioms BigN. -Module Export BigNSubPropMod := NSubPropFunct BigNAxiomsMod. +Module Export BigNPropMod := NPropFunct BigNAxiomsMod. (** Notations about [BigN] *) @@ -38,7 +38,7 @@ Bind Scope bigN_scope with bigN. Bind Scope bigN_scope with BigN.t. Bind Scope bigN_scope with BigN.t_. -Notation Local "0" := BigN.zero : bigN_scope. (* temporary notation *) +Local Notation "0" := BigN.zero : bigN_scope. (* temporary notation *) Infix "+" := BigN.add : bigN_scope. Infix "-" := BigN.sub : bigN_scope. Infix "*" := BigN.mul : bigN_scope. diff --git a/theories/Numbers/Natural/Binary/NBinDefs.v b/theories/Numbers/Natural/Binary/NBinDefs.v deleted file mode 100644 index d2fe94dad..000000000 --- a/theories/Numbers/Natural/Binary/NBinDefs.v +++ /dev/null @@ -1,226 +0,0 @@ -(************************************************************************) -(* v * The Coq Proof Assistant / The Coq Development Team *) -(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) -(* \VV/ **************************************************************) -(* // * This file is distributed under the terms of the *) -(* * GNU Lesser General Public License Version 2.1 *) -(************************************************************************) -(* Evgeny Makarov, INRIA, 2007 *) -(************************************************************************) - -(*i $Id$ i*) - -Require Import BinPos. -Require Export BinNat. -Require Import NSub. - -Open Local Scope N_scope. - -(** Implementation of [NAxiomsSig] module type via [BinNat.N] *) - -Module NBinaryAxiomsMod <: NAxiomsSig. -Module Export NZOrdAxiomsMod <: NZOrdAxiomsSig. -Module Export NZAxiomsMod <: NZAxiomsSig. - -Definition NZ := N. -Definition NZeq := @eq N. -Definition NZ0 := N0. -Definition NZsucc := Nsucc. -Definition NZpred := Npred. -Definition NZadd := Nplus. -Definition NZsub := Nminus. -Definition NZmul := Nmult. - -Instance NZeq_equiv : Equivalence NZeq. -Program Instance NZsucc_wd : Proper (eq==>eq) NZsucc. -Program Instance NZpred_wd : Proper (eq==>eq) NZpred. -Program Instance NZadd_wd : Proper (eq==>eq==>eq) NZadd. -Program Instance NZsub_wd : Proper (eq==>eq==>eq) NZsub. -Program Instance NZmul_wd : Proper (eq==>eq==>eq) NZmul. - -Theorem NZinduction : - forall A : NZ -> Prop, Proper (NZeq==>iff) A -> - A N0 -> (forall n, A n <-> A (NZsucc n)) -> forall n : NZ, A n. -Proof. -intros A A_wd A0 AS. apply Nrect. assumption. intros; now apply -> AS. -Qed. - -Theorem NZpred_succ : forall n : NZ, NZpred (NZsucc n) = n. -Proof. -destruct n as [| p]; simpl. reflexivity. -case_eq (Psucc p); try (intros q H; rewrite <- H; now rewrite Ppred_succ). -intro H; false_hyp H Psucc_not_one. -Qed. - -Theorem NZadd_0_l : forall n : NZ, N0 + n = n. -Proof. -reflexivity. -Qed. - -Theorem NZadd_succ_l : forall n m : NZ, (NZsucc n) + m = NZsucc (n + m). -Proof. -destruct n; destruct m. -simpl in |- *; reflexivity. -unfold NZsucc, NZadd, Nsucc, Nplus. rewrite <- Pplus_one_succ_l; reflexivity. -simpl in |- *; reflexivity. -simpl in |- *; rewrite Pplus_succ_permute_l; reflexivity. -Qed. - -Theorem NZsub_0_r : forall n : NZ, n - N0 = n. -Proof. -now destruct n. -Qed. - -Theorem NZsub_succ_r : forall n m : NZ, n - (NZsucc m) = NZpred (n - m). -Proof. -destruct n as [| p]; destruct m as [| q]; try reflexivity. -now destruct p. -simpl. rewrite Pminus_mask_succ_r, Pminus_mask_carry_spec. -now destruct (Pminus_mask p q) as [| r |]; [| destruct r |]. -Qed. - -Theorem NZmul_0_l : forall n : NZ, N0 * n = N0. -Proof. -destruct n; reflexivity. -Qed. - -Theorem NZmul_succ_l : forall n m : NZ, (NZsucc n) * m = n * m + m. -Proof. -destruct n as [| n]; destruct m as [| m]; simpl; try reflexivity. -now rewrite Pmult_Sn_m, Pplus_comm. -Qed. - -End NZAxiomsMod. - -Definition NZlt := Nlt. -Definition NZle := Nle. -Definition NZmin := Nmin. -Definition NZmax := Nmax. - -Program Instance NZlt_wd : Proper (eq==>eq==>iff) NZlt. -Program Instance NZle_wd : Proper (eq==>eq==>iff) NZle. -Program Instance NZmin_wd : Proper (eq==>eq==>eq) NZmin. -Program Instance NZmax_wd : Proper (eq==>eq==>eq) NZmax. - -Theorem NZlt_eq_cases : forall n m : N, n <= m <-> n < m \/ n = m. -Proof. -intros n m. unfold Nle, Nlt. rewrite <- Ncompare_eq_correct. -destruct (n ?= m); split; intro H1; (try discriminate); try (now left); try now right. -now elim H1. destruct H1; discriminate. -Qed. - -Theorem NZlt_irrefl : forall n : NZ, ~ n < n. -Proof. -intro n; unfold Nlt; now rewrite Ncompare_refl. -Qed. - -Theorem NZlt_succ_r : forall n m : NZ, n < (NZsucc m) <-> n <= m. -Proof. -intros n m; unfold Nlt, Nle; destruct n as [| p]; destruct m as [| q]; simpl; -split; intro H; try reflexivity; try discriminate. -destruct p; simpl; intros; discriminate. exfalso; now apply H. -apply -> Pcompare_p_Sq in H. destruct H as [H | H]. -now rewrite H. now rewrite H, Pcompare_refl. -apply <- Pcompare_p_Sq. case_eq ((p ?= q)%positive Eq); intro H1. -right; now apply Pcompare_Eq_eq. now left. exfalso; now apply H. -Qed. - -Theorem NZmin_l : forall n m : N, n <= m -> NZmin n m = n. -Proof. -unfold NZmin, Nmin, Nle; intros n m H. -destruct (n ?= m); try reflexivity. now elim H. -Qed. - -Theorem NZmin_r : forall n m : N, m <= n -> NZmin n m = m. -Proof. -unfold NZmin, Nmin, Nle; intros n m H. -case_eq (n ?= m); intro H1; try reflexivity. -now apply -> Ncompare_eq_correct. -rewrite <- Ncompare_antisym, H1 in H; elim H; auto. -Qed. - -Theorem NZmax_l : forall n m : N, m <= n -> NZmax n m = n. -Proof. -unfold NZmax, Nmax, Nle; intros n m H. -case_eq (n ?= m); intro H1; try reflexivity. -symmetry; now apply -> Ncompare_eq_correct. -rewrite <- Ncompare_antisym, H1 in H; elim H; auto. -Qed. - -Theorem NZmax_r : forall n m : N, n <= m -> NZmax n m = m. -Proof. -unfold NZmax, Nmax, Nle; intros n m H. -destruct (n ?= m); try reflexivity. now elim H. -Qed. - -End NZOrdAxiomsMod. - -Definition recursion (A : Type) (a : A) (f : N -> A -> A) (n : N) := - Nrect (fun _ => A) a f n. -Implicit Arguments recursion [A]. - -Theorem pred_0 : Npred N0 = N0. -Proof. -reflexivity. -Qed. - -Instance recursion_wd A (Aeq : relation A) : - Proper (Aeq==>(eq==>Aeq==>Aeq)==>eq==>Aeq) (@recursion A). -Proof. -intros A Aeq a a' Eaa' f f' Eff'. -intro x; pattern x; apply Nrect. -intros x' H; now rewrite <- H. -clear x. -intros x IH x' H; rewrite <- H. -unfold recursion in *. do 2 rewrite Nrect_step. -now apply Eff'; [| apply IH]. -Qed. - -Theorem recursion_0 : - forall (A : Type) (a : A) (f : N -> A -> A), recursion a f N0 = a. -Proof. -intros A a f; unfold recursion; now rewrite Nrect_base. -Qed. - -Theorem recursion_succ : - forall (A : Type) (Aeq : relation A) (a : A) (f : N -> A -> A), - Aeq a a -> Proper (eq==>Aeq==>Aeq) f -> - forall n : N, Aeq (recursion a f (Nsucc n)) (f n (recursion a f n)). -Proof. -unfold recursion; intros A Aeq a f EAaa f_wd n; pattern n; apply Nrect. -rewrite Nrect_step; rewrite Nrect_base; now apply f_wd. -clear n; intro n; do 2 rewrite Nrect_step; intro IH. apply f_wd; [reflexivity|]. -now rewrite Nrect_step. -Qed. - -End NBinaryAxiomsMod. - -Module Export NBinarySubPropMod := NSubPropFunct NBinaryAxiomsMod. - -(* -Require Import NDefOps. -Module Import NBinaryDefOpsMod := NdefOpsPropFunct NBinaryAxiomsMod. - -(* Some fun comparing the efficiency of the generic log defined -by strong (course-of-value) recursion and the log defined by recursion -on notation *) - -Time Eval vm_compute in (log 500000). (* 11 sec *) - -Fixpoint binposlog (p : positive) : N := -match p with -| xH => 0 -| xO p' => Nsucc (binposlog p') -| xI p' => Nsucc (binposlog p') -end. - -Definition binlog (n : N) : N := -match n with -| 0 => 0 -| Npos p => binposlog p -end. - -Time Eval vm_compute in (binlog 500000). (* 0 sec *) -Time Eval vm_compute in (binlog 1000000000000000000000000000000). (* 0 sec *) - -*)
\ No newline at end of file diff --git a/theories/Numbers/Natural/Binary/NBinary.v b/theories/Numbers/Natural/Binary/NBinary.v index 558f2d0e4..e94644c48 100644 --- a/theories/Numbers/Natural/Binary/NBinary.v +++ b/theories/Numbers/Natural/Binary/NBinary.v @@ -10,6 +10,172 @@ (*i $Id$ i*) -Require Export NBinDefs. -Require Export NArithRing. +Require Import BinPos. +Require Export BinNat. +Require Import NAxioms NProperties. +Local Open Scope N_scope. + +(** * Implementation of [NAxiomsSig] module type via [BinNat.N] *) + +Module NBinaryAxiomsMod <: NAxiomsSig. + +(** Bi-directional induction. *) + +Theorem bi_induction : + forall A : N -> Prop, Proper (eq==>iff) A -> + A N0 -> (forall n, A n <-> A (Nsucc n)) -> forall n : N, A n. +Proof. +intros A A_wd A0 AS. apply Nrect. assumption. intros; now apply -> AS. +Qed. + +(** Basic operations. *) + +Instance eq_equiv : Equivalence (@eq N). +Program Instance succ_wd : Proper (eq==>eq) Nsucc. +Program Instance pred_wd : Proper (eq==>eq) Npred. +Program Instance add_wd : Proper (eq==>eq==>eq) Nplus. +Program Instance sub_wd : Proper (eq==>eq==>eq) Nminus. +Program Instance mul_wd : Proper (eq==>eq==>eq) Nmult. + +Definition pred_succ := Npred_succ. +Definition add_0_l := Nplus_0_l. +Definition add_succ_l := Nplus_succ. +Definition sub_0_r := Nminus_0_r. +Definition sub_succ_r := Nminus_succ_r. +Definition mul_0_l := Nmult_0_l. +Definition mul_succ_l n m := eq_trans (Nmult_Sn_m n m) (Nplus_comm _ _). + +(** Order *) + +Program Instance lt_wd : Proper (eq==>eq==>iff) Nlt. + +Definition lt_eq_cases := Nle_lteq. +Definition lt_irrefl := Nlt_irrefl. + +Theorem lt_succ_r : forall n m, n < (Nsucc m) <-> n <= m. +Proof. +intros n m; unfold Nlt, Nle; destruct n as [| p]; destruct m as [| q]; simpl; +split; intro H; try reflexivity; try discriminate. +destruct p; simpl; intros; discriminate. exfalso; now apply H. +apply -> Pcompare_p_Sq in H. destruct H as [H | H]. +now rewrite H. now rewrite H, Pcompare_refl. +apply <- Pcompare_p_Sq. case_eq ((p ?= q)%positive Eq); intro H1. +right; now apply Pcompare_Eq_eq. now left. exfalso; now apply H. +Qed. + +Theorem min_l : forall n m, n <= m -> Nmin n m = n. +Proof. +unfold Nmin, Nle; intros n m H. +destruct (n ?= m); try reflexivity. now elim H. +Qed. + +Theorem min_r : forall n m, m <= n -> Nmin n m = m. +Proof. +unfold Nmin, Nle; intros n m H. +case_eq (n ?= m); intro H1; try reflexivity. +now apply -> Ncompare_eq_correct. +rewrite <- Ncompare_antisym, H1 in H; elim H; auto. +Qed. + +Theorem max_l : forall n m, m <= n -> Nmax n m = n. +Proof. +unfold Nmax, Nle; intros n m H. +case_eq (n ?= m); intro H1; try reflexivity. +symmetry; now apply -> Ncompare_eq_correct. +rewrite <- Ncompare_antisym, H1 in H; elim H; auto. +Qed. + +Theorem max_r : forall n m : N, n <= m -> Nmax n m = m. +Proof. +unfold Nmax, Nle; intros n m H. +destruct (n ?= m); try reflexivity. now elim H. +Qed. + +(** Part specific to natural numbers, not integers. *) + +Theorem pred_0 : Npred 0 = 0. +Proof. +reflexivity. +Qed. + +Definition recursion (A : Type) : A -> (N -> A -> A) -> N -> A := + Nrect (fun _ => A). +Implicit Arguments recursion [A]. + +Instance recursion_wd A (Aeq : relation A) : + Proper (Aeq==>(eq==>Aeq==>Aeq)==>eq==>Aeq) (@recursion A). +Proof. +intros A Aeq a a' Eaa' f f' Eff'. +intro x; pattern x; apply Nrect. +intros x' H; now rewrite <- H. +clear x. +intros x IH x' H; rewrite <- H. +unfold recursion in *. do 2 rewrite Nrect_step. +now apply Eff'; [| apply IH]. +Qed. + +Theorem recursion_0 : + forall (A : Type) (a : A) (f : N -> A -> A), recursion a f N0 = a. +Proof. +intros A a f; unfold recursion; now rewrite Nrect_base. +Qed. + +Theorem recursion_succ : + forall (A : Type) (Aeq : relation A) (a : A) (f : N -> A -> A), + Aeq a a -> Proper (eq==>Aeq==>Aeq) f -> + forall n : N, Aeq (recursion a f (Nsucc n)) (f n (recursion a f n)). +Proof. +unfold recursion; intros A Aeq a f EAaa f_wd n; pattern n; apply Nrect. +rewrite Nrect_step; rewrite Nrect_base; now apply f_wd. +clear n; intro n; do 2 rewrite Nrect_step; intro IH. apply f_wd; [reflexivity|]. +now rewrite Nrect_step. +Qed. + +(** The instantiation of operations. + Placing them at the very end avoids having indirections in above lemmas. *) + +Definition t := N. +Definition eq := @eq N. +Definition zero := N0. +Definition succ := Nsucc. +Definition pred := Npred. +Definition add := Nplus. +Definition sub := Nminus. +Definition mul := Nmult. +Definition lt := Nlt. +Definition le := Nle. +Definition min := Nmin. +Definition max := Nmax. + +End NBinaryAxiomsMod. + +Module Export NBinaryPropMod := NPropFunct NBinaryAxiomsMod. + +(* +Require Import NDefOps. +Module Import NBinaryDefOpsMod := NdefOpsPropFunct NBinaryAxiomsMod. + +(* Some fun comparing the efficiency of the generic log defined +by strong (course-of-value) recursion and the log defined by recursion +on notation *) + +Time Eval vm_compute in (log 500000). (* 11 sec *) + +Fixpoint binposlog (p : positive) : N := +match p with +| xH => 0 +| xO p' => Nsucc (binposlog p') +| xI p' => Nsucc (binposlog p') +end. + +Definition binlog (n : N) : N := +match n with +| 0 => 0 +| Npos p => binposlog p +end. + +Time Eval vm_compute in (binlog 500000). (* 0 sec *) +Time Eval vm_compute in (binlog 1000000000000000000000000000000). (* 0 sec *) + +*)
\ No newline at end of file diff --git a/theories/Numbers/Natural/Peano/NPeano.v b/theories/Numbers/Natural/Peano/NPeano.v index 61171a43e..8974ef114 100644 --- a/theories/Numbers/Natural/Peano/NPeano.v +++ b/theories/Numbers/Natural/Peano/NPeano.v @@ -13,83 +13,70 @@ Require Import Arith. Require Import Min. Require Import Max. -Require Import NSub. +Require Import NAxioms NProperties. + +(** * Implementation of [NAxiomsSig] by [nat] *) Module NPeanoAxiomsMod <: NAxiomsSig. -Module Export NZOrdAxiomsMod <: NZOrdAxiomsSig. -Module Export NZAxiomsMod <: NZAxiomsSig. - -Definition NZ := nat. -Definition NZeq := (@eq nat). -Definition NZ0 := 0. -Definition NZsucc := S. -Definition NZpred := pred. -Definition NZadd := plus. -Definition NZsub := minus. -Definition NZmul := mult. - -Instance NZeq_equiv : Equivalence NZeq. -Program Instance NZsucc_wd : Proper (eq==>eq) NZsucc. -Program Instance NZpred_wd : Proper (eq==>eq) NZpred. -Program Instance NZadd_wd : Proper (eq==>eq==>eq) NZadd. -Program Instance NZsub_wd : Proper (eq==>eq==>eq) NZsub. -Program Instance NZmul_wd : Proper (eq==>eq==>eq) NZmul. - -Theorem NZinduction : + +(** Bi-directional induction. *) + +Theorem bi_induction : forall A : nat -> Prop, Proper (eq==>iff) A -> A 0 -> (forall n : nat, A n <-> A (S n)) -> forall n : nat, A n. Proof. intros A A_wd A0 AS. apply nat_ind. assumption. intros; now apply -> AS. Qed. -Theorem NZpred_succ : forall n : nat, pred (S n) = n. +(** Basic operations. *) + +Instance eq_equiv : Equivalence (@eq nat). +Program Instance succ_wd : Proper (eq==>eq) S. +Program Instance pred_wd : Proper (eq==>eq) pred. +Program Instance add_wd : Proper (eq==>eq==>eq) plus. +Program Instance sub_wd : Proper (eq==>eq==>eq) minus. +Program Instance mul_wd : Proper (eq==>eq==>eq) mult. + +Theorem pred_succ : forall n : nat, pred (S n) = n. Proof. reflexivity. Qed. -Theorem NZadd_0_l : forall n : nat, 0 + n = n. +Theorem add_0_l : forall n : nat, 0 + n = n. Proof. reflexivity. Qed. -Theorem NZadd_succ_l : forall n m : nat, (S n) + m = S (n + m). +Theorem add_succ_l : forall n m : nat, (S n) + m = S (n + m). Proof. reflexivity. Qed. -Theorem NZsub_0_r : forall n : nat, n - 0 = n. +Theorem sub_0_r : forall n : nat, n - 0 = n. Proof. intro n; now destruct n. Qed. -Theorem NZsub_succ_r : forall n m : nat, n - (S m) = pred (n - m). +Theorem sub_succ_r : forall n m : nat, n - (S m) = pred (n - m). Proof. -intros n m; induction n m using nat_double_ind; simpl; auto. apply NZsub_0_r. +intros n m; induction n m using nat_double_ind; simpl; auto. apply sub_0_r. Qed. -Theorem NZmul_0_l : forall n : nat, 0 * n = 0. +Theorem mul_0_l : forall n : nat, 0 * n = 0. Proof. reflexivity. Qed. -Theorem NZmul_succ_l : forall n m : nat, S n * m = n * m + m. +Theorem mul_succ_l : forall n m : nat, S n * m = n * m + m. Proof. intros n m; now rewrite plus_comm. Qed. -End NZAxiomsMod. - -Definition NZlt := lt. -Definition NZle := le. -Definition NZmin := min. -Definition NZmax := max. +(** Order on natural numbers *) -Program Instance NZlt_wd : Proper (eq==>eq==>iff) NZlt. -Program Instance NZle_wd : Proper (eq==>eq==>iff) NZle. -Program Instance NZmin_wd : Proper (eq==>eq==>eq) NZmin. -Program Instance NZmax_wd : Proper (eq==>eq==>eq) NZmax. +Program Instance lt_wd : Proper (eq==>eq==>iff) lt. -Theorem NZlt_eq_cases : forall n m : nat, n <= m <-> n < m \/ n = m. +Theorem lt_eq_cases : forall n m : nat, n <= m <-> n < m \/ n = m. Proof. intros n m; split. apply le_lt_or_eq. @@ -97,52 +84,47 @@ intro H; destruct H as [H | H]. now apply lt_le_weak. rewrite H; apply le_refl. Qed. -Theorem NZlt_irrefl : forall n : nat, ~ (n < n). +Theorem lt_irrefl : forall n : nat, ~ (n < n). Proof. exact lt_irrefl. Qed. -Theorem NZlt_succ_r : forall n m : nat, n < S m <-> n <= m. +Theorem lt_succ_r : forall n m : nat, n < S m <-> n <= m. Proof. intros n m; split; [apply lt_n_Sm_le | apply le_lt_n_Sm]. Qed. -Theorem NZmin_l : forall n m : nat, n <= m -> NZmin n m = n. +Theorem min_l : forall n m : nat, n <= m -> min n m = n. Proof. exact min_l. Qed. -Theorem NZmin_r : forall n m : nat, m <= n -> NZmin n m = m. +Theorem min_r : forall n m : nat, m <= n -> min n m = m. Proof. exact min_r. Qed. -Theorem NZmax_l : forall n m : nat, m <= n -> NZmax n m = n. +Theorem max_l : forall n m : nat, m <= n -> max n m = n. Proof. exact max_l. Qed. -Theorem NZmax_r : forall n m : nat, n <= m -> NZmax n m = m. +Theorem max_r : forall n m : nat, n <= m -> max n m = m. Proof. exact max_r. Qed. -End NZOrdAxiomsMod. - -Definition recursion : forall A : Type, A -> (nat -> A -> A) -> nat -> A := - fun A : Type => nat_rect (fun _ => A). -Implicit Arguments recursion [A]. - -Theorem succ_neq_0 : forall n : nat, S n <> 0. -Proof. -intros; discriminate. -Qed. +(** Facts specific to natural numbers, not integers. *) Theorem pred_0 : pred 0 = 0. Proof. reflexivity. Qed. +Definition recursion (A : Type) : A -> (nat -> A -> A) -> nat -> A := + nat_rect (fun _ => A). +Implicit Arguments recursion [A]. + Instance recursion_wd (A : Type) (Aeq : relation A) : Proper (Aeq ==> (eq==>Aeq==>Aeq) ==> eq ==> Aeq) (@recursion A). Proof. @@ -164,9 +146,25 @@ Proof. unfold Proper, respectful in *; induction n; simpl; auto. Qed. +(** The instantiation of operations. + Placing them at the very end avoids having indirections in above lemmas. *) + +Definition t := nat. +Definition eq := @eq nat. +Definition zero := 0. +Definition succ := S. +Definition pred := pred. +Definition add := plus. +Definition sub := minus. +Definition mul := mult. +Definition lt := lt. +Definition le := le. +Definition min := min. +Definition max := max. + End NPeanoAxiomsMod. (* Now we apply the largest property functor *) -Module Export NPeanoSubPropMod := NSubPropFunct NPeanoAxiomsMod. +Module Export NPeanoPropMod := NPropFunct NPeanoAxiomsMod. diff --git a/theories/Numbers/Natural/SpecViaZ/NSigNAxioms.v b/theories/Numbers/Natural/SpecViaZ/NSigNAxioms.v index 81893d9af..919701879 100644 --- a/theories/Numbers/Natural/SpecViaZ/NSigNAxioms.v +++ b/theories/Numbers/Natural/SpecViaZ/NSigNAxioms.v @@ -19,7 +19,7 @@ Module NSig_NAxioms (N:NType) <: NAxiomsSig. Delimit Scope IntScope with Int. Bind Scope IntScope with N.t. -Open Local Scope IntScope. +Local Open Scope IntScope. Notation "[ x ]" := (N.to_Z x) : IntScope. Infix "==" := N.eq (at level 70) : IntScope. Notation "0" := N.zero : IntScope. @@ -27,26 +27,17 @@ Infix "+" := N.add : IntScope. Infix "-" := N.sub : IntScope. Infix "*" := N.mul : IntScope. -Module Export NZOrdAxiomsMod <: NZOrdAxiomsSig. -Module Export NZAxiomsMod <: NZAxiomsSig. +Hint Rewrite N.spec_0 N.spec_succ N.spec_add N.spec_mul : int. +Ltac isimpl := autorewrite with int. -Definition NZ := N.t. -Definition NZeq := N.eq. -Definition NZ0 := N.zero. -Definition NZsucc := N.succ. -Definition NZpred := N.pred. -Definition NZadd := N.add. -Definition NZsub := N.sub. -Definition NZmul := N.mul. +Instance eq_equiv : Equivalence N.eq. -Instance NZeq_equiv : Equivalence N.eq. - -Instance NZsucc_wd : Proper (N.eq==>N.eq) NZsucc. +Instance succ_wd : Proper (N.eq==>N.eq) N.succ. Proof. -unfold N.eq; repeat red; intros; rewrite 2 N.spec_succ; f_equal; auto. +unfold N.eq; repeat red; intros; isimpl; f_equal; auto. Qed. -Instance NZpred_wd : Proper (N.eq==>N.eq) NZpred. +Instance pred_wd : Proper (N.eq==>N.eq) N.pred. Proof. unfold N.eq; repeat red; intros. generalize (N.spec_pos y) (N.spec_pos x) (N.spec_eq_bool x 0). @@ -55,12 +46,12 @@ rewrite 2 N.spec_pred0; congruence. rewrite 2 N.spec_pred; f_equal; auto; try omega. Qed. -Instance NZadd_wd : Proper (N.eq==>N.eq==>N.eq) NZadd. +Instance add_wd : Proper (N.eq==>N.eq==>N.eq) N.add. Proof. -unfold N.eq; repeat red; intros; rewrite 2 N.spec_add; f_equal; auto. +unfold N.eq; repeat red; intros; isimpl; f_equal; auto. Qed. -Instance NZsub_wd : Proper (N.eq==>N.eq==>N.eq) NZsub. +Instance sub_wd : Proper (N.eq==>N.eq==>N.eq) N.sub. Proof. unfold N.eq; intros x x' Hx y y' Hy. destruct (Z_lt_le_dec [x] [y]). @@ -68,12 +59,12 @@ rewrite 2 N.spec_sub0; f_equal; congruence. rewrite 2 N.spec_sub; f_equal; congruence. Qed. -Instance NZmul_wd : Proper (N.eq==>N.eq==>N.eq) NZmul. +Instance mul_wd : Proper (N.eq==>N.eq==>N.eq) N.mul. Proof. -unfold N.eq; repeat red; intros; rewrite 2 N.spec_mul; f_equal; auto. +unfold N.eq; repeat red; intros; isimpl; f_equal; auto. Qed. -Theorem NZpred_succ : forall n, N.pred (N.succ n) == n. +Theorem pred_succ : forall n, N.pred (N.succ n) == n. Proof. unfold N.eq; repeat red; intros. rewrite N.spec_pred; rewrite N.spec_succ. @@ -114,7 +105,7 @@ Proof. exact (natlike_ind B B0 BS). Qed. -Theorem NZinduction : forall n, A n. +Theorem bi_induction : forall n, A n. Proof. intro n. setoid_replace n with (N_of_Z (N.to_Z n)). apply B_holds. apply N.spec_pos. @@ -125,23 +116,23 @@ Qed. End Induction. -Theorem NZadd_0_l : forall n, 0 + n == n. +Theorem add_0_l : forall n, 0 + n == n. Proof. -intros; red; rewrite N.spec_add, N.spec_0; auto with zarith. +intros; red; isimpl; auto with zarith. Qed. -Theorem NZadd_succ_l : forall n m, (N.succ n) + m == N.succ (n + m). +Theorem add_succ_l : forall n m, (N.succ n) + m == N.succ (n + m). Proof. -intros; red; rewrite N.spec_add, 2 N.spec_succ, N.spec_add; auto with zarith. +intros; red; isimpl; auto with zarith. Qed. -Theorem NZsub_0_r : forall n, n - 0 == n. +Theorem sub_0_r : forall n, n - 0 == n. Proof. intros; red; rewrite N.spec_sub; rewrite N.spec_0; auto with zarith. apply N.spec_pos. Qed. -Theorem NZsub_succ_r : forall n m, n - (N.succ m) == N.pred (n - m). +Theorem sub_succ_r : forall n m, n - (N.succ m) == N.pred (n - m). Proof. intros; red. destruct (Z_lt_le_dec [n] [N.succ m]) as [H|H]. @@ -157,24 +148,19 @@ rewrite N.spec_pred, N.spec_sub; auto with zarith. rewrite N.spec_sub; auto with zarith. Qed. -Theorem NZmul_0_l : forall n, 0 * n == 0. +Theorem mul_0_l : forall n, 0 * n == 0. Proof. intros; red. rewrite N.spec_mul, N.spec_0; auto with zarith. Qed. -Theorem NZmul_succ_l : forall n m, (N.succ n) * m == n * m + m. +Theorem mul_succ_l : forall n m, (N.succ n) * m == n * m + m. Proof. intros; red. rewrite N.spec_add, 2 N.spec_mul, N.spec_succ; ring. Qed. -End NZAxiomsMod. - -Definition NZlt := N.lt. -Definition NZle := N.le. -Definition NZmin := N.min. -Definition NZmax := N.max. +(** Order *) Infix "<=" := N.le : IntScope. Infix "<" := N.lt : IntScope. @@ -214,67 +200,52 @@ intros x x' Hx y y' Hy. rewrite 2 spec_compare_alt. unfold N.eq in *. rewrite Hx, Hy; intuition. Qed. -Instance NZlt_wd : Proper (N.eq ==> N.eq ==> iff) N.lt. +Instance lt_wd : Proper (N.eq ==> N.eq ==> iff) N.lt. Proof. intros x x' Hx y y' Hy; unfold N.lt; rewrite Hx, Hy; intuition. Qed. -Instance NZle_wd : Proper (N.eq ==> N.eq ==> iff) N.le. -Proof. -intros x x' Hx y y' Hy; unfold N.le; rewrite Hx, Hy; intuition. -Qed. - -Instance NZmin_wd : Proper (N.eq ==> N.eq ==> N.eq) N.min. -Proof. -repeat red; intros; rewrite 2 spec_min; congruence. -Qed. - -Instance NZmax_wd : Proper (N.eq ==> N.eq ==> N.eq) N.max. -Proof. -repeat red; intros; rewrite 2 spec_max; congruence. -Qed. - -Theorem NZlt_eq_cases : forall n m, n <= m <-> n < m \/ n == m. +Theorem lt_eq_cases : forall n m, n <= m <-> n < m \/ n == m. Proof. intros. unfold N.eq; rewrite spec_lt, spec_le; omega. Qed. -Theorem NZlt_irrefl : forall n, ~ n < n. +Theorem lt_irrefl : forall n, ~ n < n. Proof. intros; rewrite spec_lt; auto with zarith. Qed. -Theorem NZlt_succ_r : forall n m, n < (N.succ m) <-> n <= m. +Theorem lt_succ_r : forall n m, n < (N.succ m) <-> n <= m. Proof. intros; rewrite spec_lt, spec_le, N.spec_succ; omega. Qed. -Theorem NZmin_l : forall n m, n <= m -> N.min n m == n. +Theorem min_l : forall n m, n <= m -> N.min n m == n. Proof. intros n m; unfold N.eq; rewrite spec_le, spec_min. generalize (Zmin_spec [n] [m]); omega. Qed. -Theorem NZmin_r : forall n m, m <= n -> N.min n m == m. +Theorem min_r : forall n m, m <= n -> N.min n m == m. Proof. intros n m; unfold N.eq; rewrite spec_le, spec_min. generalize (Zmin_spec [n] [m]); omega. Qed. -Theorem NZmax_l : forall n m, m <= n -> N.max n m == n. +Theorem max_l : forall n m, m <= n -> N.max n m == n. Proof. intros n m; unfold N.eq; rewrite spec_le, spec_max. generalize (Zmax_spec [n] [m]); omega. Qed. -Theorem NZmax_r : forall n m, n <= m -> N.max n m == m. +Theorem max_r : forall n m, n <= m -> N.max n m == m. Proof. intros n m; unfold N.eq; rewrite spec_le, spec_max. generalize (Zmax_spec [n] [m]); omega. Qed. -End NZOrdAxiomsMod. +(** Properties specific to natural numbers, not integers. *) Theorem pred_0 : N.pred 0 == 0. Proof. @@ -336,4 +307,20 @@ generalize (N.spec_pos n); auto with zarith. apply N.spec_pos; auto. Qed. +(** The instantiation of operations. + Placing them at the very end avoids having indirections in above lemmas. *) + +Definition t := N.t. +Definition eq := N.eq. +Definition zero := N.zero. +Definition succ := N.succ. +Definition pred := N.pred. +Definition add := N.add. +Definition sub := N.sub. +Definition mul := N.mul. +Definition lt := N.lt. +Definition le := N.le. +Definition min := N.min. +Definition max := N.max. + End NSig_NAxioms. diff --git a/theories/Numbers/Rational/BigQ/QMake.v b/theories/Numbers/Rational/BigQ/QMake.v index 0973b7d8d..59bd57084 100644 --- a/theories/Numbers/Rational/BigQ/QMake.v +++ b/theories/Numbers/Rational/BigQ/QMake.v @@ -36,7 +36,7 @@ Module Make (N:NType)(Z:ZType)(Import NZ:NType_ZType N Z) <: QType. (** Specification with respect to [QArith] *) - Open Local Scope Q_scope. + Local Open Scope Q_scope. Definition of_Z x: t := Qz (Z.of_Z x). |