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Require Import TestSuite.admit.
(* compile en user 3m39.915s sur cachalot *)
Require Import Nsatz.
(* Example with a generic domain *)
Section test.
Context {A:Type}`{Aid:Integral_domain A}.
Lemma example3 : forall x y z,
x+y+z==0 ->
x*y+x*z+y*z==0->
x*y*z==0 -> x^3%Z==0.
Proof.
Time nsatz.
Qed.
Lemma example4 : forall x y z u,
x+y+z+u==0 ->
x*y+x*z+x*u+y*z+y*u+z*u==0->
x*y*z+x*y*u+x*z*u+y*z*u==0->
x*y*z*u==0 -> x^4%Z==0.
Proof.
Time nsatz.
Qed.
Lemma example5 : forall x y z u v,
x+y+z+u+v==0 ->
x*y+x*z+x*u+x*v+y*z+y*u+y*v+z*u+z*v+u*v==0->
x*y*z+x*y*u+x*y*v+x*z*u+x*z*v+x*u*v+y*z*u+y*z*v+y*u*v+z*u*v==0->
x*y*z*u+y*z*u*v+z*u*v*x+u*v*x*y+v*x*y*z==0 ->
x*y*z*u*v==0 -> x^5%Z==0.
Proof.
Time nsatz.
Qed.
Goal forall x y:Z, x = y -> (x+0)%Z = (y*1+0)%Z.
nsatz.
Qed.
Require Import Reals.
Goal forall x y:R, x = y -> (x+0)%R = (y*1+0)%R.
nsatz.
Qed.
Goal forall a b c x:R, a = b -> b = c -> (a*a)%R = (c*c)%R.
nsatz.
Qed.
End test.
Section Geometry.
(* See the interactive pictures of Laurent Théry
on http://www-sop.inria.fr/marelle/CertiGeo/
and research paper on
https://docs.google.com/fileview?id=0ByhB3nPmbnjTYzFiZmIyNGMtYTkwNC00NWFiLWJiNzEtODM4NmVkYTc2NTVk&hl=fr
*)
Require Import List.
Require Import Reals.
Record point:Type:={
X:R;
Y:R}.
Definition collinear(A B C:point):=
(X A - X B)*(Y C - Y B)-(Y A - Y B)*(X C - X B)=0.
Definition parallel (A B C D:point):=
((X A)-(X B))*((Y C)-(Y D))=((Y A)-(Y B))*((X C)-(X D)).
Definition notparallel (A B C D:point)(x:R):=
x*(((X A)-(X B))*((Y C)-(Y D))-((Y A)-(Y B))*((X C)-(X D)))=1.
Definition orthogonal (A B C D:point):=
((X A)-(X B))*((X C)-(X D))+((Y A)-(Y B))*((Y C)-(Y D))=0.
Definition equal2(A B:point):=
(X A)=(X B) /\ (Y A)=(Y B).
Definition equal3(A B:point):=
((X A)-(X B))^2%Z+((Y A)-(Y B))^2%Z = 0.
Definition nequal2(A B:point):=
(X A)<>(X B) \/ (Y A)<>(Y B).
Definition nequal3(A B:point):=
not (((X A)-(X B))^2%Z+((Y A)-(Y B))^2%Z = 0).
Definition middle(A B I:point):=
2%R*(X I)=(X A)+(X B) /\ 2%R*(Y I)=(Y A)+(Y B).
Definition distance2(A B:point):=
(X B - X A)^2%Z + (Y B - Y A)^2%Z.
(* AB = CD *)
Definition samedistance2(A B C D:point):=
(X B - X A)^2%Z + (Y B - Y A)^2%Z = (X D - X C)^2%Z + (Y D - Y C)^2%Z.
Definition determinant(A O B:point):=
(X A - X O)*(Y B - Y O) - (Y A - Y O)*(X B - X O).
Definition scalarproduct(A O B:point):=
(X A - X O)*(X B - X O) + (Y A - Y O)*(Y B - Y O).
Definition norm2(A O B:point):=
((X A - X O)^2%Z+(Y A - Y O)^2%Z)*((X B - X O)^2%Z+(Y B - Y O)^2%Z).
Definition equaldistance(A B C D:point):=
((X B) - (X A))^2%Z + ((Y B) - (Y A))^2%Z =
((X D) - (X C))^2%Z + ((Y D) - (Y C))^2%Z.
Definition equaltangente(A B C D E F:point):=
let s1:= determinant A B C in
let c1:= scalarproduct A B C in
let s2:= determinant D E F in
let c2:= scalarproduct D E F in
s1 * c2 = s2 * c1.
Ltac cnf2 f :=
match f with
| ?A \/ (?B /\ ?C) =>
let c1 := cnf2 (A\/B) in
let c2 := cnf2 (A\/C) in constr:(c1/\c2)
| (?B /\ ?C) \/ ?A =>
let c1 := cnf2 (B\/A) in
let c2 := cnf2 (C\/A) in constr:(c1/\c2)
| (?A \/ ?B) \/ ?C =>
let c1 := cnf2 (B\/C) in cnf2 (A \/ c1)
| _ => f
end
with cnf f :=
match f with
| ?A \/ ?B =>
let c1 := cnf A in
let c2 := cnf B in
cnf2 (c1 \/ c2)
| ?A /\ ?B =>
let c1 := cnf A in
let c2 := cnf B in
constr:(c1 /\ c2)
| _ => f
end.
Ltac scnf :=
match goal with
| |- ?f => let c := cnf f in
assert c;[repeat split| tauto]
end.
Ltac disj_to_pol f :=
match f with
| ?a = ?b \/ ?g => let p := disj_to_pol g in constr:((a - b)* p)
| ?a = ?b => constr:(a - b)
end.
Lemma fastnsatz1:forall x y:R, x - y = 0 -> x = y.
nsatz.
Qed.
Ltac fastnsatz:=
try trivial; try apply fastnsatz1; try trivial; nsatz.
Ltac proof_pol_disj :=
match goal with
| |- ?g => let p := disj_to_pol g in
let h := fresh "hp" in
assert (h:p = 0);
[idtac|
prod_disj h p]
| _ => idtac
end
with prod_disj h p :=
match goal with
| |- ?a = ?b \/ ?g =>
match p with
| ?q * ?p1 =>
let h0 := fresh "hp" in
let h1 := fresh "hp" in
let h2 := fresh "hp" in
assert (h0:a - b = 0 \/ p1 = 0);
[apply Rmult_integral; exact h|
destruct h0 as [h1|h2];
[left; fastnsatz|
right; prod_disj h2 p1]]
end
| _ => fastnsatz
end.
(*
Goal forall a b c d e f:R, a=b \/ c=d \/ e=f \/ e=a.
intros. scnf; proof_pol_disj .
admit.*)
Ltac geo_unfold :=
unfold collinear, parallel, notparallel, orthogonal,
equal2, equal3, nequal2, nequal3,
middle, samedistance2,
determinant, scalarproduct, norm2, distance2,
equaltangente, determinant, scalarproduct, equaldistance.
Ltac geo_rewrite_hyps:=
repeat (match goal with
| h:X _ = _ |- _ => rewrite h in *; clear h
| h:Y _ = _ |- _ => rewrite h in *; clear h
end).
Ltac geo_split_hyps:=
repeat (match goal with
| h:_ /\ _ |- _ => destruct h
end).
Ltac geo_begin:=
geo_unfold;
intros;
geo_rewrite_hyps;
geo_split_hyps;
scnf; proof_pol_disj.
(* Examples *)
Lemma medians: forall A B C A1 B1 C1 H:point,
middle B C A1 ->
middle A C B1 ->
middle A B C1 ->
collinear A A1 H -> collinear B B1 H ->
collinear C C1 H
\/ collinear A B C.
Proof. geo_begin.
idtac "Medians".
Time nsatz.
(*Finished transaction in 2. secs (2.69359u,0.s)
*) Qed.
Lemma Pythagore: forall A B C:point,
orthogonal A B A C ->
distance2 A C + distance2 A B = distance2 B C.
Proof. geo_begin.
idtac "Pythagore".
Time nsatz.
(*Finished transaction in 0. secs (0.354946u,0.s)
*) Qed.
Lemma Thales: forall O A B C D:point,
collinear O A C -> collinear O B D ->
parallel A B C D ->
(distance2 O B * distance2 O C = distance2 O D * distance2 O A
/\ distance2 O B * distance2 C D = distance2 O D * distance2 A B)
\/ collinear O A B.
geo_begin.
idtac "Thales".
Time nsatz. (*Finished transaction in 2. secs (1.598757u,0.s)*)
Time nsatz.
Qed.
Lemma segments_of_chords: forall A B C D M O:point,
equaldistance O A O B ->
equaldistance O A O C ->
equaldistance O A O D ->
collinear A B M ->
collinear C D M ->
(distance2 M A) * (distance2 M B) = (distance2 M C) * (distance2 M D)
\/ parallel A B C D.
Proof.
geo_begin.
idtac "segments_of_chords".
Time nsatz.
(*Finished transaction in 3. secs (2.704589u,0.s)
*) Qed.
Lemma isoceles: forall A B C:point,
equaltangente A B C B C A ->
distance2 A B = distance2 A C
\/ collinear A B C.
Proof. geo_begin. Time nsatz.
(*Finished transaction in 1. secs (1.140827u,0.s)*) Qed.
Lemma minh: forall A B C D O E H I:point,
X A = 0 -> Y A = 0 -> Y O = 0 ->
equaldistance O A O B ->
equaldistance O A O C ->
equaldistance O A O D ->
orthogonal A C B D ->
collinear A C E ->
collinear B D E ->
collinear A B H ->
orthogonal E H A B ->
collinear C D I ->
middle C D I ->
collinear H E I
\/ (X C)^2%Z * (X B)^5%Z * (X O)^2%Z
* (X C - 2%Z * X O)^3%Z * (-2%Z * X O + X B)=0
\/ parallel A C B D.
Proof. geo_begin.
idtac "minh".
Time nsatz with radicalmax :=1%N strategy:=1%Z
parameters:=(X O::X B::X C::nil)
variables:= (@nil R).
(*Finished transaction in 13. secs (10.102464u,0.s)
*)
Qed.
Lemma Pappus: forall A B C A1 B1 C1 P Q S:point,
X A = 0 -> Y A = 0 -> Y B = 0 -> Y C = 0 ->
collinear A1 B1 C1 ->
collinear A B1 P -> collinear A1 B P ->
collinear A C1 Q -> collinear A1 C Q ->
collinear B C1 S -> collinear B1 C S ->
collinear P Q S
\/ (Y A1 - Y B1)^2%Z=0 \/ (X A = X B1)
\/ (X A1 = X C) \/ (X C = X B1)
\/ parallel A B1 A1 B \/ parallel A C1 A1 C \/ parallel B C1 B1 C.
Proof.
geo_begin.
idtac "Pappus".
Time nsatz with radicalmax :=1%N strategy:=0%Z
parameters:=(X B::X A1::Y A1::X B1::Y B1::X C::Y C1::nil)
variables:= (X B
:: X A1
:: Y A1
:: X B1
:: Y B1
:: X C
:: Y C1
:: X C1 :: Y P :: X P :: Y Q :: X Q :: Y S :: X S :: nil).
(*Finished transaction in 8. secs (7.795815u,0.000999999999999s)
*)
Qed.
Lemma Simson: forall A B C O D E F G:point,
X A = 0 -> Y A = 0 ->
equaldistance O A O B ->
equaldistance O A O C ->
equaldistance O A O D ->
orthogonal E D B C ->
collinear B C E ->
orthogonal F D A C ->
collinear A C F ->
orthogonal G D A B ->
collinear A B G ->
collinear E F G
\/ (X C)^2%Z = 0 \/ (Y C)^2%Z = 0 \/ (X B)^2%Z = 0 \/ (Y B)^2%Z = 0 \/ (Y C - Y B)^2%Z = 0
\/ equal3 B A
\/ equal3 A C \/ (X C - X B)^2%Z = 0
\/ equal3 B C.
Proof.
geo_begin.
idtac "Simson".
Time nsatz with radicalmax :=1%N strategy:=0%Z
parameters:=(X B::Y B::X C::Y C::Y D::nil)
variables:= (@nil R). (* compute -[X Y]. *)
(*Finished transaction in 8. secs (7.550852u,0.s)
*)
Qed.
Lemma threepoints: forall A B C A1 B1 A2 B2 H1 H2 H3:point,
(* H1 intersection of bisections *)
middle B C A1 -> orthogonal H1 A1 B C ->
middle A C B1 -> orthogonal H1 B1 A C ->
(* H2 intersection of medians *)
collinear A A1 H2 -> collinear B B1 H2 ->
(* H3 intersection of altitudes *)
collinear B C A2 -> orthogonal A A2 B C ->
collinear A C B2 -> orthogonal B B2 A C ->
collinear A A1 H3 -> collinear B B1 H3 ->
collinear H1 H2 H3
\/ collinear A B C.
Proof. geo_begin.
idtac "threepoints".
Time nsatz.
(*Finished transaction in 7. secs (6.282045u,0.s)
*) Qed.
Lemma Feuerbach: forall A B C A1 B1 C1 O A2 B2 C2 O2:point,
forall r r2:R,
X A = 0 -> Y A = 0 -> X B = 1 -> Y B = 0->
middle A B C1 -> middle B C A1 -> middle C A B1 ->
distance2 O A1 = distance2 O B1 ->
distance2 O A1 = distance2 O C1 ->
collinear A B C2 -> orthogonal A B O2 C2 ->
collinear B C A2 -> orthogonal B C O2 A2 ->
collinear A C B2 -> orthogonal A C O2 B2 ->
distance2 O2 A2 = distance2 O2 B2 ->
distance2 O2 A2 = distance2 O2 C2 ->
r^2%Z = distance2 O A1 ->
r2^2%Z = distance2 O2 A2 ->
distance2 O O2 = (r + r2)^2%Z
\/ distance2 O O2 = (r - r2)^2%Z
\/ collinear A B C.
Proof. geo_begin.
idtac "Feuerbach".
Time nsatz.
(*Finished transaction in 21. secs (19.021109u,0.s)*)
Qed.
Lemma Euler_circle: forall A B C A1 B1 C1 A2 B2 C2 O:point,
middle A B C1 -> middle B C A1 -> middle C A B1 ->
orthogonal A B C C2 -> collinear A B C2 ->
orthogonal B C A A2 -> collinear B C A2 ->
orthogonal A C B B2 -> collinear A C B2 ->
distance2 O A1 = distance2 O B1 ->
distance2 O A1 = distance2 O C1 ->
(distance2 O A2 = distance2 O A1
/\distance2 O B2 = distance2 O A1
/\distance2 O C2 = distance2 O A1)
\/ collinear A B C.
Proof. geo_begin.
idtac "Euler_circle 3 goals".
Time nsatz.
(*Finished transaction in 13. secs (11.208296u,0.124981s)*)
Time nsatz.
(*Finished transaction in 10. secs (8.846655u,0.s)*)
Time nsatz.
(*Finished transaction in 11. secs (9.186603u,0.s)*)
Qed.
Lemma Desargues: forall A B C A1 B1 C1 P Q R S:point,
X S = 0 -> Y S = 0 -> Y A = 0 ->
collinear A S A1 -> collinear B S B1 -> collinear C S C1 ->
collinear B1 C1 P -> collinear B C P ->
collinear A1 C1 Q -> collinear A C Q ->
collinear A1 B1 R -> collinear A B R ->
collinear P Q R
\/ X A = X B \/ X A = X C \/ X B = X C \/ X A = 0 \/ Y B = 0 \/ Y C = 0
\/ collinear S B C \/ parallel A C A1 C1 \/ parallel A B A1 B1.
Proof.
geo_begin.
idtac "Desargues".
Time
let lv := rev (X A
:: X B
:: Y B
:: X C
:: Y C
:: Y A1 :: X A1
:: Y B1
:: Y C1
:: X R
:: Y R
:: X Q
:: Y Q :: X P :: Y P :: X C1 :: X B1 :: nil) in
nsatz with radicalmax :=1%N strategy:=0%Z
parameters:=(X A::X B::Y B::X C::Y C::X A1::Y B1::Y C1::nil)
variables:= lv. (*Finished transaction in 8. secs (8.02578u,0.001s)*)
Qed.
Lemma chords: forall O A B C D M:point,
equaldistance O A O B ->
equaldistance O A O C ->
equaldistance O A O D ->
collinear A B M -> collinear C D M ->
scalarproduct A M B = scalarproduct C M D
\/ parallel A B C D.
Proof. geo_begin.
idtac "chords".
Time nsatz.
(*Finished transaction in 4. secs (3.959398u,0.s)*)
Qed.
Lemma Ceva: forall A B C D E F M:point,
collinear M A D -> collinear M B E -> collinear M C F ->
collinear B C D -> collinear E A C -> collinear F A B ->
(distance2 D B) * (distance2 E C) * (distance2 F A) =
(distance2 D C) * (distance2 E A) * (distance2 F B)
\/ collinear A B C.
Proof. geo_begin.
idtac "Ceva".
Time nsatz.
(*Finished transaction in 105. secs (104.121171u,0.474928s)*)
Qed.
Lemma bissectrices: forall A B C M:point,
equaltangente C A M M A B ->
equaltangente A B M M B C ->
equaltangente B C M M C A
\/ equal3 A B.
Proof. geo_begin.
idtac "bissectrices".
Time nsatz.
(*Finished transaction in 2. secs (1.937705u,0.s)*)
Qed.
Lemma bisections: forall A B C A1 B1 C1 H:point,
middle B C A1 -> orthogonal H A1 B C ->
middle A C B1 -> orthogonal H B1 A C ->
middle A B C1 ->
orthogonal H C1 A B
\/ collinear A B C.
Proof. geo_begin.
idtac "bisections".
Time nsatz. (*Finished transaction in 2. secs (2.024692u,0.002s)*)
Qed.
Lemma altitudes: forall A B C A1 B1 C1 H:point,
collinear B C A1 -> orthogonal A A1 B C ->
collinear A C B1 -> orthogonal B B1 A C ->
collinear A B C1 -> orthogonal C C1 A B ->
collinear A A1 H -> collinear B B1 H ->
collinear C C1 H
\/ equal2 A B
\/ collinear A B C.
Proof. geo_begin.
idtac "altitudes".
Time nsatz. (*Finished transaction in 3. secs (3.001544u,0.s)*)
Time nsatz. (*Finished transaction in 4. secs (3.113527u,0.s)*)
Qed.
Lemma hauteurs:forall A B C A1 B1 C1 H:point,
collinear B C A1 -> orthogonal A A1 B C ->
collinear A C B1 -> orthogonal B B1 A C ->
collinear A B C1 -> orthogonal C C1 A B ->
collinear A A1 H -> collinear B B1 H ->
collinear C C1 H
\/ collinear A B C.
geo_begin.
idtac "hauteurs".
Time
let lv := constr:(Y A1
:: X A1 :: Y B1 :: X B1 :: Y A :: Y B :: X B :: X A :: X H :: Y C
:: Y C1 :: Y H :: X C1 :: X C :: (@Datatypes.nil R)) in
nsatz with radicalmax := 2%N strategy := 1%Z parameters := (@Datatypes.nil R)
variables := lv.
(*Finished transaction in 5. secs (4.360337u,0.008999s)*)
Qed.
End Geometry.
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