From 5b7eafd0f00a16d78f99a27f5c7d5a0de77dc7e6 Mon Sep 17 00:00:00 2001 From: Stephane Glondu Date: Wed, 21 Jul 2010 09:46:51 +0200 Subject: Imported Upstream snapshot 8.3~beta0+13298 --- plugins/setoid_ring/ArithRing.v | 60 + plugins/setoid_ring/BinList.v | 93 ++ plugins/setoid_ring/Field.v | 10 + plugins/setoid_ring/Field_tac.v | 571 +++++++++ plugins/setoid_ring/Field_theory.v | 1946 ++++++++++++++++++++++++++++++ plugins/setoid_ring/InitialRing.v | 908 ++++++++++++++ plugins/setoid_ring/NArithRing.v | 21 + plugins/setoid_ring/RealField.v | 134 ++ plugins/setoid_ring/Ring.v | 44 + plugins/setoid_ring/Ring_base.v | 17 + plugins/setoid_ring/Ring_equiv.v | 74 ++ plugins/setoid_ring/Ring_polynom.v | 1781 +++++++++++++++++++++++++++ plugins/setoid_ring/Ring_tac.v | 434 +++++++ plugins/setoid_ring/Ring_theory.v | 608 ++++++++++ plugins/setoid_ring/ZArithRing.v | 60 + plugins/setoid_ring/newring.ml4 | 1164 ++++++++++++++++++ plugins/setoid_ring/newring_plugin.mllib | 2 + plugins/setoid_ring/vo.itarget | 15 + 18 files changed, 7942 insertions(+) create mode 100644 plugins/setoid_ring/ArithRing.v create mode 100644 plugins/setoid_ring/BinList.v create mode 100644 plugins/setoid_ring/Field.v create mode 100644 plugins/setoid_ring/Field_tac.v create mode 100644 plugins/setoid_ring/Field_theory.v create mode 100644 plugins/setoid_ring/InitialRing.v create mode 100644 plugins/setoid_ring/NArithRing.v create mode 100644 plugins/setoid_ring/RealField.v create mode 100644 plugins/setoid_ring/Ring.v create mode 100644 plugins/setoid_ring/Ring_base.v create mode 100644 plugins/setoid_ring/Ring_equiv.v create mode 100644 plugins/setoid_ring/Ring_polynom.v create mode 100644 plugins/setoid_ring/Ring_tac.v create mode 100644 plugins/setoid_ring/Ring_theory.v create mode 100644 plugins/setoid_ring/ZArithRing.v create mode 100644 plugins/setoid_ring/newring.ml4 create mode 100644 plugins/setoid_ring/newring_plugin.mllib create mode 100644 plugins/setoid_ring/vo.itarget (limited to 'plugins/setoid_ring') diff --git a/plugins/setoid_ring/ArithRing.v b/plugins/setoid_ring/ArithRing.v new file mode 100644 index 00000000..e5a4c8d1 --- /dev/null +++ b/plugins/setoid_ring/ArithRing.v @@ -0,0 +1,60 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* constr:(N_of_nat t) + | _ => constr:InitialRing.NotConstant + end. + +Ltac Ss_to_add f acc := + match f with + | S ?f1 => Ss_to_add f1 (S acc) + | _ => constr:(acc + f)%nat + end. + +Ltac natprering := + match goal with + |- context C [S ?p] => + match p with + O => fail 1 (* avoid replacing 1 with 1+0 ! *) + | p => match isnatcst p with + | true => fail 1 + | false => let v := Ss_to_add p (S 0) in + fold v; natprering + end + end + | _ => idtac + end. + +Add Ring natr : natSRth + (morphism nat_morph_N, constants [natcst], preprocess [natprering]). + diff --git a/plugins/setoid_ring/BinList.v b/plugins/setoid_ring/BinList.v new file mode 100644 index 00000000..d403c9ef --- /dev/null +++ b/plugins/setoid_ring/BinList.v @@ -0,0 +1,93 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* tail l + | xO p => jump p (jump p l) + | xI p => jump p (jump p (tail l)) + end. + + Fixpoint nth (p:positive) (l:list A) {struct p} : A:= + match p with + | xH => hd default l + | xO p => nth p (jump p l) + | xI p => nth p (jump p (tail l)) + end. + + Lemma jump_tl : forall j l, tail (jump j l) = jump j (tail l). + Proof. + induction j;simpl;intros. + repeat rewrite IHj;trivial. + repeat rewrite IHj;trivial. + trivial. + Qed. + + Lemma jump_Psucc : forall j l, + (jump (Psucc j) l) = (jump 1 (jump j l)). + Proof. + induction j;simpl;intros. + repeat rewrite IHj;simpl;repeat rewrite jump_tl;trivial. + repeat rewrite jump_tl;trivial. + trivial. + Qed. + + Lemma jump_Pplus : forall i j l, + (jump (i + j) l) = (jump i (jump j l)). + Proof. + induction i;intros. + rewrite xI_succ_xO;rewrite Pplus_one_succ_r. + rewrite <- Pplus_diag;repeat rewrite <- Pplus_assoc. + repeat rewrite IHi. + rewrite Pplus_comm;rewrite <- Pplus_one_succ_r;rewrite jump_Psucc;trivial. + rewrite <- Pplus_diag;repeat rewrite <- Pplus_assoc. + repeat rewrite IHi;trivial. + rewrite Pplus_comm;rewrite <- Pplus_one_succ_r;rewrite jump_Psucc;trivial. + Qed. + + Lemma jump_Pdouble_minus_one : forall i l, + (jump (Pdouble_minus_one i) (tail l)) = (jump i (jump i l)). + Proof. + induction i;intros;simpl. + repeat rewrite jump_tl;trivial. + rewrite IHi. do 2 rewrite <- jump_tl;rewrite IHi;trivial. + trivial. + Qed. + + + Lemma nth_jump : forall p l, nth p (tail l) = hd default (jump p l). + Proof. + induction p;simpl;intros. + rewrite <-jump_tl;rewrite IHp;trivial. + rewrite <-jump_tl;rewrite IHp;trivial. + trivial. + Qed. + + Lemma nth_Pdouble_minus_one : + forall p l, nth (Pdouble_minus_one p) (tail l) = nth p (jump p l). + Proof. + induction p;simpl;intros. + repeat rewrite jump_tl;trivial. + rewrite jump_Pdouble_minus_one. + repeat rewrite <- jump_tl;rewrite IHp;trivial. + trivial. + Qed. + +End MakeBinList. + + diff --git a/plugins/setoid_ring/Field.v b/plugins/setoid_ring/Field.v new file mode 100644 index 00000000..a944ba5f --- /dev/null +++ b/plugins/setoid_ring/Field.v @@ -0,0 +1,10 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* + match t with + | (radd ?t1 ?t2) => + fun _ => + let e1 := mkP t1 in + let e2 := mkP t2 in constr:(FEadd e1 e2) + | (rmul ?t1 ?t2) => + fun _ => + let e1 := mkP t1 in + let e2 := mkP t2 in constr:(FEmul e1 e2) + | (rsub ?t1 ?t2) => + fun _ => + let e1 := mkP t1 in + let e2 := mkP t2 in constr:(FEsub e1 e2) + | (ropp ?t1) => + fun _ => let e1 := mkP t1 in constr:(FEopp e1) + | (rdiv ?t1 ?t2) => + fun _ => + let e1 := mkP t1 in + let e2 := mkP t2 in constr:(FEdiv e1 e2) + | (rinv ?t1) => + fun _ => let e1 := mkP t1 in constr:(FEinv e1) + | (rpow ?t1 ?n) => + match CstPow n with + | InitialRing.NotConstant => + fun _ => + let p := Find_at t fv in + constr:(@FEX C p) + | ?c => fun _ => let e1 := mkP t1 in constr:(FEpow e1 c) + end + | _ => + fun _ => + let p := Find_at t fv in + constr:(@FEX C p) + end + | ?c => fun _ => constr:(FEc c) + end in + f () + in mkP t. + +Ltac FFV Cst CstPow add mul sub opp div inv pow t fv := + let rec TFV t fv := + match Cst t with + | InitialRing.NotConstant => + match t with + | (add ?t1 ?t2) => TFV t2 ltac:(TFV t1 fv) + | (mul ?t1 ?t2) => TFV t2 ltac:(TFV t1 fv) + | (sub ?t1 ?t2) => TFV t2 ltac:(TFV t1 fv) + | (opp ?t1) => TFV t1 fv + | (div ?t1 ?t2) => TFV t2 ltac:(TFV t1 fv) + | (inv ?t1) => TFV t1 fv + | (pow ?t1 ?n) => + match CstPow n with + | InitialRing.NotConstant => + AddFvTail t fv + | _ => TFV t1 fv + end + | _ => AddFvTail t fv + end + | _ => fv + end + in TFV t fv. + +(* packaging the field structure *) + +(* TODO: inline PackField into field_lookup *) +Ltac PackField F req Cst_tac Pow_tac L1 L2 L3 L4 cond_ok pre post := + let FLD := + match type of L1 with + | context [req (@FEeval ?R ?rO ?radd ?rmul ?rsub ?ropp ?rdiv ?rinv + ?C ?phi ?Cpow ?Cp_phi ?rpow _ _) _ ] => + (fun proj => + proj Cst_tac Pow_tac pre post + req radd rmul rsub ropp rdiv rinv rpow C L1 L2 L3 L4 cond_ok) + | _ => fail 1 "field anomaly: bad correctness lemma (parse)" + end in + F FLD. + +Ltac get_FldPre FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + pre). + +Ltac get_FldPost FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + post). + +Ltac get_L1 FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + L1). + +Ltac get_SimplifyEqLemma FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + L2). + +Ltac get_SimplifyLemma FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + L3). + +Ltac get_L4 FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + L4). + +Ltac get_CondLemma FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + cond_ok). + +Ltac get_FldEq FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + req). + +Ltac get_FldCarrier FLD := + let req := get_FldEq FLD in + relation_carrier req. + +Ltac get_RingFV FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + FV Cst_tac Pow_tac radd rmul rsub ropp rpow). + +Ltac get_FFV FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + FFV Cst_tac Pow_tac radd rmul rsub ropp rdiv rinv rpow). + +Ltac get_RingMeta FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + mkPolexpr C Cst_tac Pow_tac radd rmul rsub ropp rpow). + +Ltac get_Meta FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + mkFieldexpr C Cst_tac Pow_tac radd rmul rsub ropp rdiv rinv rpow). + +Ltac get_Hyp_tac FLD := + FLD ltac: + (fun Cst_tac Pow_tac pre post req radd rmul rsub ropp rdiv rinv rpow C + L1 L2 L3 L4 cond_ok => + let mkPol := mkPolexpr C Cst_tac Pow_tac radd rmul rsub ropp rpow in + fun fv lH => mkHyp_tac C req ltac:(fun t => mkPol t fv) lH). + +Ltac get_FEeval FLD := + let L1 := get_L1 FLD in + match type of L1 with + | context + [(@FEeval + ?R ?r0 ?add ?mul ?sub ?opp ?div ?inv ?C ?phi ?Cpow ?powphi ?pow _ _)] => + constr:(@FEeval R r0 add mul sub opp div inv C phi Cpow powphi pow) + | _ => fail 1 "field anomaly: bad correctness lemma (get_FEeval)" + end. + +(* simplifying the non-zero condition... *) + +Ltac fold_field_cond req := + let rec fold_concl t := + match t with + ?x /\ ?y => + let fx := fold_concl x in let fy := fold_concl y in constr:(fx/\fy) + | req ?x ?y -> False => constr:(~ req x y) + | _ => t + end in + let ft := fold_concl Get_goal in + change ft. + +Ltac simpl_PCond FLD := + let req := get_FldEq FLD in + let lemma := get_CondLemma FLD in + try apply lemma; + protect_fv "field_cond"; + fold_field_cond req; + try exact I. + +Ltac simpl_PCond_BEURK FLD := + let req := get_FldEq FLD in + let lemma := get_CondLemma FLD in + apply lemma; + protect_fv "field_cond"; + fold_field_cond req. + +(* Rewriting (field_simplify) *) +Ltac Field_norm_gen f n FLD lH rl := + let mkFV := get_RingFV FLD in + let mkFFV := get_FFV FLD in + let mkFE := get_Meta FLD in + let fv0 := FV_hypo_tac mkFV ltac:(get_FldEq FLD) lH in + let lemma_tac fv kont := + let lemma := get_SimplifyLemma FLD in + (* reify equations of the context *) + let lpe := get_Hyp_tac FLD fv lH in + let vlpe := fresh "hyps" in + pose (vlpe := lpe); + let prh := proofHyp_tac lH in + (* compute the normal form of the reified hyps *) + let vlmp := fresh "hyps'" in + let vlmp_eq := fresh "hyps_eq" in + let mk_monpol := get_MonPol lemma in + compute_assertion vlmp_eq vlmp (mk_monpol vlpe); + (* partially instantiate the lemma *) + let lem := fresh "f_rw_lemma" in + (assert (lem := lemma n vlpe fv prh vlmp vlmp_eq) + || fail "type error when building the rewriting lemma"); + (* continuation will call main_tac for all reified terms *) + kont lem; + (* at the end, cleanup *) + (clear lem vlmp_eq vlmp vlpe||idtac"Field_norm_gen:cleanup failed") in + (* each instance of the lemma is simplified then passed to f *) + let main_tac H := protect_fv "field" in H; f H in + (* generate and use equations for each expression *) + ReflexiveRewriteTactic mkFFV mkFE lemma_tac main_tac fv0 rl; + try simpl_PCond FLD. + +Ltac Field_simplify_gen f FLD lH rl := + get_FldPre FLD (); + Field_norm_gen f ring_subst_niter FLD lH rl; + get_FldPost FLD (). + +Ltac Field_simplify := + Field_simplify_gen ltac:(fun H => rewrite H). + +Tactic Notation (at level 0) "field_simplify" constr_list(rl) := + let G := Get_goal in + field_lookup (PackField Field_simplify) [] rl G. + +Tactic Notation (at level 0) + "field_simplify" "[" constr_list(lH) "]" constr_list(rl) := + let G := Get_goal in + field_lookup (PackField Field_simplify) [lH] rl G. + +Tactic Notation "field_simplify" constr_list(rl) "in" hyp(H):= + let G := Get_goal in + let t := type of H in + let g := fresh "goal" in + set (g:= G); + revert H; + field_lookup (PackField Field_simplify) [] rl t; + intro H; + unfold g;clear g. + +Tactic Notation "field_simplify" + "["constr_list(lH) "]" constr_list(rl) "in" hyp(H):= + let G := Get_goal in + let t := type of H in + let g := fresh "goal" in + set (g:= G); + revert H; + field_lookup (PackField Field_simplify) [lH] rl t; + intro H; + unfold g;clear g. + +(* +Ltac Field_simplify_in hyp:= + Field_simplify_gen ltac:(fun H => rewrite H in hyp). + +Tactic Notation (at level 0) + "field_simplify" constr_list(rl) "in" hyp(h) := + let t := type of h in + field_lookup (Field_simplify_in h) [] rl t. + +Tactic Notation (at level 0) + "field_simplify" "[" constr_list(lH) "]" constr_list(rl) "in" hyp(h) := + let t := type of h in + field_lookup (Field_simplify_in h) [lH] rl t. +*) + +(** Generic tactic for solving equations *) + +Ltac Field_Scheme Simpl_tac n lemma FLD lH := + let req := get_FldEq FLD in + let mkFV := get_RingFV FLD in + let mkFFV := get_FFV FLD in + let mkFE := get_Meta FLD in + let Main_eq t1 t2 := + let fv := FV_hypo_tac mkFV req lH in + let fv := mkFFV t1 fv in + let fv := mkFFV t2 fv in + let lpe := get_Hyp_tac FLD fv lH in + let prh := proofHyp_tac lH in + let vlpe := fresh "list_hyp" in + let fe1 := mkFE t1 fv in + let fe2 := mkFE t2 fv in + pose (vlpe := lpe); + let nlemma := fresh "field_lemma" in + (assert (nlemma := lemma n fv vlpe fe1 fe2 prh) + || fail "field anomaly:failed to build lemma"); + ProveLemmaHyps nlemma + ltac:(fun ilemma => + apply ilemma + || fail "field anomaly: failed in applying lemma"; + [ Simpl_tac | simpl_PCond FLD]); + clear nlemma; + subst vlpe in + OnEquation req Main_eq. + +(* solve completely a field equation, leaving non-zero conditions to be + proved (field) *) + +Ltac FIELD FLD lH rl := + let Simpl := vm_compute; reflexivity || fail "not a valid field equation" in + let lemma := get_L1 FLD in + get_FldPre FLD (); + Field_Scheme Simpl Ring_tac.ring_subst_niter lemma FLD lH; + try exact I; + get_FldPost FLD(). + +Tactic Notation (at level 0) "field" := + let G := Get_goal in + field_lookup (PackField FIELD) [] G. + +Tactic Notation (at level 0) "field" "[" constr_list(lH) "]" := + let G := Get_goal in + field_lookup (PackField FIELD) [lH] G. + +(* transforms a field equation to an equivalent (simplified) ring equation, + and leaves non-zero conditions to be proved (field_simplify_eq) *) +Ltac FIELD_SIMPL FLD lH rl := + let Simpl := (protect_fv "field") in + let lemma := get_SimplifyEqLemma FLD in + get_FldPre FLD (); + Field_Scheme Simpl Ring_tac.ring_subst_niter lemma FLD lH; + get_FldPost FLD (). + +Tactic Notation (at level 0) "field_simplify_eq" := + let G := Get_goal in + field_lookup (PackField FIELD_SIMPL) [] G. + +Tactic Notation (at level 0) "field_simplify_eq" "[" constr_list(lH) "]" := + let G := Get_goal in + field_lookup (PackField FIELD_SIMPL) [lH] G. + +(* Same as FIELD_SIMPL but in hypothesis *) + +Ltac Field_simplify_eq n FLD lH := + let req := get_FldEq FLD in + let mkFV := get_RingFV FLD in + let mkFFV := get_FFV FLD in + let mkFE := get_Meta FLD in + let lemma := get_L4 FLD in + let hyp := fresh "hyp" in + intro hyp; + OnEquationHyp req hyp ltac:(fun t1 t2 => + let fv := FV_hypo_tac mkFV req lH in + let fv := mkFFV t1 fv in + let fv := mkFFV t2 fv in + let lpe := get_Hyp_tac FLD fv lH in + let prh := proofHyp_tac lH in + let fe1 := mkFE t1 fv in + let fe2 := mkFE t2 fv in + let vlpe := fresh "vlpe" in + ProveLemmaHyps (lemma n fv lpe fe1 fe2 prh) + ltac:(fun ilemma => + match type of ilemma with + | req _ _ -> _ -> ?EQ => + let tmp := fresh "tmp" in + assert (tmp : EQ); + [ apply ilemma; [ exact hyp | simpl_PCond_BEURK FLD] + | protect_fv "field" in tmp; revert tmp ]; + clear hyp + end)). + +Ltac FIELD_SIMPL_EQ FLD lH rl := + get_FldPre FLD (); + Field_simplify_eq Ring_tac.ring_subst_niter FLD lH; + get_FldPost FLD (). + +Tactic Notation (at level 0) "field_simplify_eq" "in" hyp(H) := + let t := type of H in + generalize H; + field_lookup (PackField FIELD_SIMPL_EQ) [] t; + [ try exact I + | clear H;intro H]. + + +Tactic Notation (at level 0) + "field_simplify_eq" "[" constr_list(lH) "]" "in" hyp(H) := + let t := type of H in + generalize H; + field_lookup (PackField FIELD_SIMPL_EQ) [lH] t; + [ try exact I + |clear H;intro H]. + +(* More generic tactics to build variants of field *) + +(* This tactic reifies c and pass to F: + - the FLD structure gathering all info in the field DB + - the atom list + - the expression (FExpr) + *) +Ltac gen_with_field F c := + let MetaExpr FLD _ rl := + let R := get_FldCarrier FLD in + let mkFFV := get_FFV FLD in + let mkFE := get_Meta FLD in + let csr := + match rl with + | List.cons ?r _ => r + | _ => fail 1 "anomaly: ill-formed list" + end in + let fv := mkFFV csr (@List.nil R) in + let expr := mkFE csr fv in + F FLD fv expr in + field_lookup (PackField MetaExpr) [] (c=c). + + +(* pushes the equation expr = ope(expr) in the goal, and + discharge it with field *) +Ltac prove_field_eqn ope FLD fv expr := + let res := ope expr in + let expr' := fresh "input_expr" in + pose (expr' := expr); + let res' := fresh "result" in + pose (res' := res); + let lemma := get_L1 FLD in + let lemma := + constr:(lemma O fv List.nil expr' res' I List.nil (refl_equal _)) in + let ty := type of lemma in + let lhs := match ty with + forall _, ?lhs=_ -> _ => lhs + end in + let rhs := match ty with + forall _, _=_ -> forall _, ?rhs=_ -> _ => rhs + end in + let lhs' := fresh "lhs" in let lhs_eq := fresh "lhs_eq" in + let rhs' := fresh "rhs" in let rhs_eq := fresh "rhs_eq" in + compute_assertion lhs_eq lhs' lhs; + compute_assertion rhs_eq rhs' rhs; + let H := fresh "fld_eqn" in + refine (_ (lemma lhs' lhs_eq rhs' rhs_eq _ _)); + (* main goal *) + [intro H;protect_fv "field" in H; revert H + (* ring-nf(lhs') = ring-nf(rhs') *) + | vm_compute; reflexivity || fail "field cannot prove this equality" + (* denominator condition *) + | simpl_PCond FLD]; + clear lhs_eq rhs_eq; subst lhs' rhs'. + +Ltac prove_with_field ope c := + gen_with_field ltac:(prove_field_eqn ope) c. + +(* Prove an equation x=ope(x) and rewrite with it *) +Ltac prove_rw ope x := + prove_with_field ope x; + [ let H := fresh "Heq_maple" in + intro H; rewrite H; clear H + |..]. + +(* Apply ope (FExpr->FExpr) on an expression *) +Ltac reduce_field_expr ope kont FLD fv expr := + let evfun := get_FEeval FLD in + let res := ope expr in + let c := (eval simpl_field_expr in (evfun fv res)) in + kont c. + +(* Hack to let a Ltac return a term in the context of a primitive tactic *) +Ltac return_term x := generalize (refl_equal x). +Ltac get_term := + match goal with + | |- ?x = _ -> _ => x + end. + +(* Turn an operation on field expressions (FExpr) into a reduction + on terms (in the field carrier). Because of field_lookup, + the tactic cannot return a term directly, so it is returned + via the conclusion of the goal (return_term). *) +Ltac reduce_field_ope ope c := + gen_with_field ltac:(reduce_field_expr ope return_term) c. + + +(* Adding a new field *) + +Ltac ring_of_field f := + match type of f with + | almost_field_theory _ _ _ _ _ _ _ _ _ => constr:(AF_AR f) + | field_theory _ _ _ _ _ _ _ _ _ => constr:(F_R f) + | semi_field_theory _ _ _ _ _ _ _ => constr:(SF_SR f) + end. + +Ltac coerce_to_almost_field set ext f := + match type of f with + | almost_field_theory _ _ _ _ _ _ _ _ _ => f + | field_theory _ _ _ _ _ _ _ _ _ => constr:(F2AF set ext f) + | semi_field_theory _ _ _ _ _ _ _ => constr:(SF2AF set f) + end. + +Ltac field_elements set ext fspec pspec sspec dspec rk := + let afth := coerce_to_almost_field set ext fspec in + let rspec := ring_of_field fspec in + ring_elements set ext rspec pspec sspec dspec rk + ltac:(fun arth ext_r morph p_spec s_spec d_spec f => f afth ext_r morph p_spec s_spec d_spec). + +Ltac field_lemmas set ext inv_m fspec pspec sspec dspec rk := + let get_lemma := + match pspec with None => fun x y => x | _ => fun x y => y end in + let simpl_eq_lemma := get_lemma + Field_simplify_eq_correct Field_simplify_eq_pow_correct in + let simpl_eq_in_lemma := get_lemma + Field_simplify_eq_in_correct Field_simplify_eq_pow_in_correct in + let rw_lemma := get_lemma + Field_rw_correct Field_rw_pow_correct in + field_elements set ext fspec pspec sspec dspec rk + ltac:(fun afth ext_r morph p_spec s_spec d_spec => + match morph with + | _ => + let field_ok1 := constr:(Field_correct set ext_r inv_m afth morph) in + match p_spec with + | mkhypo ?pp_spec => + let field_ok2 := constr:(field_ok1 _ _ _ pp_spec) in + match s_spec with + | mkhypo ?ss_spec => + let field_ok3 := constr:(field_ok2 _ ss_spec) in + match d_spec with + | mkhypo ?dd_spec => + let field_ok := constr:(field_ok3 _ dd_spec) in + let mk_lemma lemma := + constr:(lemma _ _ _ _ _ _ _ _ _ _ + set ext_r inv_m afth + _ _ _ _ _ _ _ _ _ morph + _ _ _ pp_spec _ ss_spec _ dd_spec) in + let field_simpl_eq_ok := mk_lemma simpl_eq_lemma in + let field_simpl_ok := mk_lemma rw_lemma in + let field_simpl_eq_in := mk_lemma simpl_eq_in_lemma in + let cond1_ok := + constr:(Pcond_simpl_gen set ext_r afth morph pp_spec dd_spec) in + let cond2_ok := + constr:(Pcond_simpl_complete set ext_r afth morph pp_spec dd_spec) in + (fun f => + f afth ext_r morph field_ok field_simpl_ok field_simpl_eq_ok field_simpl_eq_in + cond1_ok cond2_ok) + | _ => fail 4 "field: bad coefficiant division specification" + end + | _ => fail 3 "field: bad sign specification" + end + | _ => fail 2 "field: bad power specification" + end + | _ => fail 1 "field internal error : field_lemmas, please report" + end). diff --git a/plugins/setoid_ring/Field_theory.v b/plugins/setoid_ring/Field_theory.v new file mode 100644 index 00000000..9617d409 --- /dev/null +++ b/plugins/setoid_ring/Field_theory.v @@ -0,0 +1,1946 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* R->R) (ropp : R->R). + Variable (rdiv : R -> R -> R) (rinv : R -> R). + Variable req : R -> R -> Prop. + + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Notation "x - y " := (rsub x y). Notation "x / y" := (rdiv x y). + Notation "- x" := (ropp x). Notation "/ x" := (rinv x). + Notation "x == y" := (req x y) (at level 70, no associativity). + + (* Equality properties *) + Variable Rsth : Setoid_Theory R req. + Variable Reqe : ring_eq_ext radd rmul ropp req. + Variable SRinv_ext : forall p q, p == q -> / p == / q. + + (* Field properties *) + Record almost_field_theory : Prop := mk_afield { + AF_AR : almost_ring_theory rO rI radd rmul rsub ropp req; + AF_1_neq_0 : ~ 1 == 0; + AFdiv_def : forall p q, p / q == p * / q; + AFinv_l : forall p, ~ p == 0 -> / p * p == 1 + }. + +Section AlmostField. + + Variable AFth : almost_field_theory. + Let ARth := AFth.(AF_AR). + Let rI_neq_rO := AFth.(AF_1_neq_0). + Let rdiv_def := AFth.(AFdiv_def). + Let rinv_l := AFth.(AFinv_l). + + (* Coefficients *) + Variable C: Type. + Variable (cO cI: C) (cadd cmul csub : C->C->C) (copp : C->C). + Variable ceqb : C->C->bool. + Variable phi : C -> R. + + Variable CRmorph : ring_morph rO rI radd rmul rsub ropp req + cO cI cadd cmul csub copp ceqb phi. + +Lemma ceqb_rect : forall c1 c2 (A:Type) (x y:A) (P:A->Type), + (phi c1 == phi c2 -> P x) -> P y -> P (if ceqb c1 c2 then x else y). +Proof. +intros. +generalize (fun h => X (morph_eq CRmorph c1 c2 h)). +case (ceqb c1 c2); auto. +Qed. + + + (* C notations *) + Notation "x +! y" := (cadd x y) (at level 50). + Notation "x *! y " := (cmul x y) (at level 40). + Notation "x -! y " := (csub x y) (at level 50). + Notation "-! x" := (copp x) (at level 35). + Notation " x ?=! y" := (ceqb x y) (at level 70, no associativity). + Notation "[ x ]" := (phi x) (at level 0). + + + (* Useful tactics *) + Add Setoid R req Rsth as R_set1. + Add Morphism radd : radd_ext. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext. exact (Ropp_ext Reqe). Qed. + Add Morphism rsub : rsub_ext. exact (ARsub_ext Rsth Reqe ARth). Qed. + Add Morphism rinv : rinv_ext. exact SRinv_ext. Qed. + +Let eq_trans := Setoid.Seq_trans _ _ Rsth. +Let eq_sym := Setoid.Seq_sym _ _ Rsth. +Let eq_refl := Setoid.Seq_refl _ _ Rsth. + +Hint Resolve eq_refl rdiv_def rinv_l rI_neq_rO CRmorph.(morph1) . +Hint Resolve (Rmul_ext Reqe) (Rmul_ext Reqe) (Radd_ext Reqe) + (ARsub_ext Rsth Reqe ARth) (Ropp_ext Reqe) SRinv_ext. +Hint Resolve (ARadd_0_l ARth) (ARadd_comm ARth) (ARadd_assoc ARth) + (ARmul_1_l ARth) (ARmul_0_l ARth) + (ARmul_comm ARth) (ARmul_assoc ARth) (ARdistr_l ARth) + (ARopp_mul_l ARth) (ARopp_add ARth) + (ARsub_def ARth) . + + (* Power coefficients *) + Variable Cpow : Set. + Variable Cp_phi : N -> Cpow. + Variable rpow : R -> Cpow -> R. + Variable pow_th : power_theory rI rmul req Cp_phi rpow. + (* sign function *) + Variable get_sign : C -> option C. + Variable get_sign_spec : sign_theory copp ceqb get_sign. + + Variable cdiv:C -> C -> C*C. + Variable cdiv_th : div_theory req cadd cmul phi cdiv. + +Notation NPEeval := (PEeval rO radd rmul rsub ropp phi Cp_phi rpow). +Notation Nnorm:= (norm_subst cO cI cadd cmul csub copp ceqb cdiv). + +Notation NPphi_dev := (Pphi_dev rO rI radd rmul rsub ropp cO cI ceqb phi get_sign). +Notation NPphi_pow := (Pphi_pow rO rI radd rmul rsub ropp cO cI ceqb phi Cp_phi rpow get_sign). + +(* add abstract semi-ring to help with some proofs *) +Add Ring Rring : (ARth_SRth ARth). + + +(* additional ring properties *) + +Lemma rsub_0_l : forall r, 0 - r == - r. +intros; rewrite (ARsub_def ARth) in |- *;ring. +Qed. + +Lemma rsub_0_r : forall r, r - 0 == r. +intros; rewrite (ARsub_def ARth) in |- *. +rewrite (ARopp_zero Rsth Reqe ARth) in |- *; ring. +Qed. + +(*************************************************************************** + + Properties of division + + ***************************************************************************) + +Theorem rdiv_simpl: forall p q, ~ q == 0 -> q * (p / q) == p. +intros p q H. +rewrite rdiv_def in |- *. +transitivity (/ q * q * p); [ ring | idtac ]. +rewrite rinv_l in |- *; auto. +Qed. +Hint Resolve rdiv_simpl . + +Theorem SRdiv_ext: + forall p1 p2, p1 == p2 -> forall q1 q2, q1 == q2 -> p1 / q1 == p2 / q2. +intros p1 p2 H q1 q2 H0. +transitivity (p1 * / q1); auto. +transitivity (p2 * / q2); auto. +Qed. +Hint Resolve SRdiv_ext . + + Add Morphism rdiv : rdiv_ext. exact SRdiv_ext. Qed. + +Lemma rmul_reg_l : forall p q1 q2, + ~ p == 0 -> p * q1 == p * q2 -> q1 == q2. +intros. +rewrite <- (@rdiv_simpl q1 p) in |- *; trivial. +rewrite <- (@rdiv_simpl q2 p) in |- *; trivial. +repeat rewrite rdiv_def in |- *. +repeat rewrite (ARmul_assoc ARth) in |- *. +auto. +Qed. + +Theorem field_is_integral_domain : forall r1 r2, + ~ r1 == 0 -> ~ r2 == 0 -> ~ r1 * r2 == 0. +Proof. +red in |- *; intros. +apply H0. +transitivity (1 * r2); auto. +transitivity (/ r1 * r1 * r2); auto. +rewrite <- (ARmul_assoc ARth) in |- *. +rewrite H1 in |- *. +apply ARmul_0_r with (1 := Rsth) (2 := ARth). +Qed. + +Theorem ropp_neq_0 : forall r, + ~ -(1) == 0 -> ~ r == 0 -> ~ -r == 0. +intros. +setoid_replace (- r) with (- (1) * r). + apply field_is_integral_domain; trivial. + rewrite <- (ARopp_mul_l ARth) in |- *. + rewrite (ARmul_1_l ARth) in |- *. + reflexivity. +Qed. + +Theorem rdiv_r_r : forall r, ~ r == 0 -> r / r == 1. +intros. +rewrite (AFdiv_def AFth) in |- *. +rewrite (ARmul_comm ARth) in |- *. +apply (AFinv_l AFth). +trivial. +Qed. + +Theorem rdiv1: forall r, r == r / 1. +intros r; transitivity (1 * (r / 1)); auto. +Qed. + +Theorem rdiv2: + forall r1 r2 r3 r4, + ~ r2 == 0 -> + ~ r4 == 0 -> + r1 / r2 + r3 / r4 == (r1 * r4 + r3 * r2) / (r2 * r4). +Proof. +intros r1 r2 r3 r4 H H0. +assert (~ r2 * r4 == 0) by complete (apply field_is_integral_domain; trivial). +apply rmul_reg_l with (r2 * r4); trivial. +rewrite rdiv_simpl in |- *; trivial. +rewrite (ARdistr_r Rsth Reqe ARth) in |- *. +apply (Radd_ext Reqe). + transitivity (r2 * (r1 / r2) * r4); [ ring | auto ]. + transitivity (r2 * (r4 * (r3 / r4))); auto. + transitivity (r2 * r3); auto. +Qed. + + +Theorem rdiv2b: + forall r1 r2 r3 r4 r5, + ~ (r2*r5) == 0 -> + ~ (r4*r5) == 0 -> + r1 / (r2*r5) + r3 / (r4*r5) == (r1 * r4 + r3 * r2) / (r2 * (r4 * r5)). +Proof. +intros r1 r2 r3 r4 r5 H H0. +assert (HH1: ~ r2 == 0) by (intros HH; case H; rewrite HH; ring). +assert (HH2: ~ r5 == 0) by (intros HH; case H; rewrite HH; ring). +assert (HH3: ~ r4 == 0) by (intros HH; case H0; rewrite HH; ring). +assert (HH4: ~ r2 * (r4 * r5) == 0) + by complete (repeat apply field_is_integral_domain; trivial). +apply rmul_reg_l with (r2 * (r4 * r5)); trivial. +rewrite rdiv_simpl in |- *; trivial. +rewrite (ARdistr_r Rsth Reqe ARth) in |- *. +apply (Radd_ext Reqe). + transitivity ((r2 * r5) * (r1 / (r2 * r5)) * r4); [ ring | auto ]. + transitivity ((r4 * r5) * (r3 / (r4 * r5)) * r2); [ ring | auto ]. +Qed. + +Theorem rdiv5: forall r1 r2, - (r1 / r2) == - r1 / r2. +intros r1 r2. +transitivity (- (r1 * / r2)); auto. +transitivity (- r1 * / r2); auto. +Qed. +Hint Resolve rdiv5 . + +Theorem rdiv3: + forall r1 r2 r3 r4, + ~ r2 == 0 -> + ~ r4 == 0 -> + r1 / r2 - r3 / r4 == (r1 * r4 - r3 * r2) / (r2 * r4). +intros r1 r2 r3 r4 H H0. +assert (~ r2 * r4 == 0) by (apply field_is_integral_domain; trivial). +transitivity (r1 / r2 + - (r3 / r4)); auto. +transitivity (r1 / r2 + - r3 / r4); auto. +transitivity ((r1 * r4 + - r3 * r2) / (r2 * r4)); auto. +apply rdiv2; auto. +apply SRdiv_ext; auto. +transitivity (r1 * r4 + - (r3 * r2)); symmetry; auto. +Qed. + + +Theorem rdiv3b: + forall r1 r2 r3 r4 r5, + ~ (r2 * r5) == 0 -> + ~ (r4 * r5) == 0 -> + r1 / (r2*r5) - r3 / (r4*r5) == (r1 * r4 - r3 * r2) / (r2 * (r4 * r5)). +Proof. +intros r1 r2 r3 r4 r5 H H0. +transitivity (r1 / (r2 * r5) + - (r3 / (r4 * r5))); auto. +transitivity (r1 / (r2 * r5) + - r3 / (r4 * r5)); auto. +transitivity ((r1 * r4 + - r3 * r2) / (r2 * (r4 * r5))). +apply rdiv2b; auto; try ring. +apply (SRdiv_ext); auto. +transitivity (r1 * r4 + - (r3 * r2)); symmetry; auto. +Qed. + +Theorem rdiv6: + forall r1 r2, + ~ r1 == 0 -> ~ r2 == 0 -> / (r1 / r2) == r2 / r1. +intros r1 r2 H H0. +assert (~ r1 / r2 == 0) as Hk. + intros H1; case H. + transitivity (r2 * (r1 / r2)); auto. + rewrite H1 in |- *; ring. + apply rmul_reg_l with (r1 / r2); auto. + transitivity (/ (r1 / r2) * (r1 / r2)); auto. + transitivity 1; auto. + repeat rewrite rdiv_def in |- *. + transitivity (/ r1 * r1 * (/ r2 * r2)); [ idtac | ring ]. + repeat rewrite rinv_l in |- *; auto. +Qed. +Hint Resolve rdiv6 . + + Theorem rdiv4: + forall r1 r2 r3 r4, + ~ r2 == 0 -> + ~ r4 == 0 -> + (r1 / r2) * (r3 / r4) == (r1 * r3) / (r2 * r4). +Proof. +intros r1 r2 r3 r4 H H0. +assert (~ r2 * r4 == 0) by complete (apply field_is_integral_domain; trivial). +apply rmul_reg_l with (r2 * r4); trivial. +rewrite rdiv_simpl in |- *; trivial. +transitivity (r2 * (r1 / r2) * (r4 * (r3 / r4))); [ ring | idtac ]. +repeat rewrite rdiv_simpl in |- *; trivial. +Qed. + + Theorem rdiv4b: + forall r1 r2 r3 r4 r5 r6, + ~ r2 * r5 == 0 -> + ~ r4 * r6 == 0 -> + ((r1 * r6) / (r2 * r5)) * ((r3 * r5) / (r4 * r6)) == (r1 * r3) / (r2 * r4). +Proof. +intros r1 r2 r3 r4 r5 r6 H H0. +rewrite rdiv4; auto. +transitivity ((r5 * r6) * (r1 * r3) / ((r5 * r6) * (r2 * r4))). +apply SRdiv_ext; ring. +assert (HH: ~ r5*r6 == 0). + apply field_is_integral_domain. + intros H1; case H; rewrite H1; ring. + intros H1; case H0; rewrite H1; ring. +rewrite <- rdiv4 ; auto. + rewrite rdiv_r_r; auto. + + apply field_is_integral_domain. + intros H1; case H; rewrite H1; ring. + intros H1; case H0; rewrite H1; ring. +Qed. + + +Theorem rdiv7: + forall r1 r2 r3 r4, + ~ r2 == 0 -> + ~ r3 == 0 -> + ~ r4 == 0 -> + (r1 / r2) / (r3 / r4) == (r1 * r4) / (r2 * r3). +Proof. +intros. +rewrite (rdiv_def (r1 / r2)) in |- *. +rewrite rdiv6 in |- *; trivial. +apply rdiv4; trivial. +Qed. + +Theorem rdiv7b: + forall r1 r2 r3 r4 r5 r6, + ~ r2 * r6 == 0 -> + ~ r3 * r5 == 0 -> + ~ r4 * r6 == 0 -> + ((r1 * r5) / (r2 * r6)) / ((r3 * r5) / (r4 * r6)) == (r1 * r4) / (r2 * r3). +Proof. +intros. +rewrite rdiv7; auto. +transitivity ((r5 * r6) * (r1 * r4) / ((r5 * r6) * (r2 * r3))). +apply SRdiv_ext; ring. +assert (HH: ~ r5*r6 == 0). + apply field_is_integral_domain. + intros H2; case H0; rewrite H2; ring. + intros H2; case H1; rewrite H2; ring. +rewrite <- rdiv4 ; auto. +rewrite rdiv_r_r; auto. + apply field_is_integral_domain. + intros H2; case H; rewrite H2; ring. + intros H2; case H0; rewrite H2; ring. +Qed. + + +Theorem rdiv8: forall r1 r2, ~ r2 == 0 -> r1 == 0 -> r1 / r2 == 0. +intros r1 r2 H H0. +transitivity (r1 * / r2); auto. +transitivity (0 * / r2); auto. +Qed. + + +Theorem cross_product_eq : forall r1 r2 r3 r4, + ~ r2 == 0 -> ~ r4 == 0 -> r1 * r4 == r3 * r2 -> r1 / r2 == r3 / r4. +intros. +transitivity (r1 / r2 * (r4 / r4)). + rewrite rdiv_r_r in |- *; trivial. + symmetry in |- *. + apply (ARmul_1_r Rsth ARth). + rewrite rdiv4 in |- *; trivial. + rewrite H1 in |- *. + rewrite (ARmul_comm ARth r2 r4) in |- *. + rewrite <- rdiv4 in |- *; trivial. + rewrite rdiv_r_r in |- * by trivial. + apply (ARmul_1_r Rsth ARth). +Qed. + +(*************************************************************************** + + Some equality test + + ***************************************************************************) + +Fixpoint positive_eq (p1 p2 : positive) {struct p1} : bool := + match p1, p2 with + xH, xH => true + | xO p3, xO p4 => positive_eq p3 p4 + | xI p3, xI p4 => positive_eq p3 p4 + | _, _ => false + end. + +Theorem positive_eq_correct: + forall p1 p2, if positive_eq p1 p2 then p1 = p2 else p1 <> p2. +intros p1; elim p1; + (try (intros p2; case p2; simpl; auto; intros; discriminate)). +intros p3 rec p2; case p2; simpl; auto; (try (intros; discriminate)); intros p4. +generalize (rec p4); case (positive_eq p3 p4); auto. +intros H1; apply f_equal with ( f := xI ); auto. +intros H1 H2; case H1; injection H2; auto. +intros p3 rec p2; case p2; simpl; auto; (try (intros; discriminate)); intros p4. +generalize (rec p4); case (positive_eq p3 p4); auto. +intros H1; apply f_equal with ( f := xO ); auto. +intros H1 H2; case H1; injection H2; auto. +Qed. + +Definition N_eq n1 n2 := + match n1, n2 with + | N0, N0 => true + | Npos p1, Npos p2 => positive_eq p1 p2 + | _, _ => false + end. + +Lemma N_eq_correct : forall n1 n2, if N_eq n1 n2 then n1 = n2 else n1 <> n2. +Proof. + intros [ |p1] [ |p2];simpl;trivial;try(intro H;discriminate H;fail). + assert (H:=positive_eq_correct p1 p2);destruct (positive_eq p1 p2); + [rewrite H;trivial | intro H1;injection H1;subst;apply H;trivial]. +Qed. + +(* equality test *) +Fixpoint PExpr_eq (e1 e2 : PExpr C) {struct e1} : bool := + match e1, e2 with + PEc c1, PEc c2 => ceqb c1 c2 + | PEX p1, PEX p2 => positive_eq p1 p2 + | PEadd e3 e5, PEadd e4 e6 => if PExpr_eq e3 e4 then PExpr_eq e5 e6 else false + | PEsub e3 e5, PEsub e4 e6 => if PExpr_eq e3 e4 then PExpr_eq e5 e6 else false + | PEmul e3 e5, PEmul e4 e6 => if PExpr_eq e3 e4 then PExpr_eq e5 e6 else false + | PEopp e3, PEopp e4 => PExpr_eq e3 e4 + | PEpow e3 n3, PEpow e4 n4 => if N_eq n3 n4 then PExpr_eq e3 e4 else false + | _, _ => false + end. + +Add Morphism (pow_pos rmul) with signature req ==> eq ==> req as pow_morph. +intros x y H p;induction p as [p IH| p IH|];simpl;auto;ring[IH]. +Qed. + +Add Morphism (pow_N rI rmul) with signature req ==> eq ==> req as pow_N_morph. +intros x y H [|p];simpl;auto. apply pow_morph;trivial. +Qed. +(* +Lemma rpow_morph : forall x y n, x == y ->rpow x (Cp_phi n) == rpow y (Cp_phi n). +Proof. + intros; repeat rewrite pow_th.(rpow_pow_N). + destruct n;simpl. apply eq_refl. + induction p;simpl;try rewrite IHp;try rewrite H; apply eq_refl. +Qed. +*) +Theorem PExpr_eq_semi_correct: + forall l e1 e2, PExpr_eq e1 e2 = true -> NPEeval l e1 == NPEeval l e2. +intros l e1; elim e1. +intros c1; intros e2; elim e2; simpl; (try (intros; discriminate)). +intros c2; apply (morph_eq CRmorph). +intros p1; intros e2; elim e2; simpl; (try (intros; discriminate)). +intros p2; generalize (positive_eq_correct p1 p2); case (positive_eq p1 p2); + (try (intros; discriminate)); intros H; rewrite H; auto. +intros e3 rec1 e5 rec2 e2; case e2; simpl; (try (intros; discriminate)). +intros e4 e6; generalize (rec1 e4); case (PExpr_eq e3 e4); + (try (intros; discriminate)); generalize (rec2 e6); case (PExpr_eq e5 e6); + (try (intros; discriminate)); auto. +intros e3 rec1 e5 rec2 e2; case e2; simpl; (try (intros; discriminate)). +intros e4 e6; generalize (rec1 e4); case (PExpr_eq e3 e4); + (try (intros; discriminate)); generalize (rec2 e6); case (PExpr_eq e5 e6); + (try (intros; discriminate)); auto. +intros e3 rec1 e5 rec2 e2; case e2; simpl; (try (intros; discriminate)). +intros e4 e6; generalize (rec1 e4); case (PExpr_eq e3 e4); + (try (intros; discriminate)); generalize (rec2 e6); case (PExpr_eq e5 e6); + (try (intros; discriminate)); auto. +intros e3 rec e2; (case e2; simpl; (try (intros; discriminate))). +intros e4; generalize (rec e4); case (PExpr_eq e3 e4); + (try (intros; discriminate)); auto. +intros e3 rec n3 e2;(case e2;simpl;(try (intros;discriminate))). +intros e4 n4;generalize (N_eq_correct n3 n4);destruct (N_eq n3 n4); +intros;try discriminate. +repeat rewrite pow_th.(rpow_pow_N);rewrite H;rewrite (rec _ H0);auto. +Qed. + +(* add *) +Definition NPEadd e1 e2 := + match e1, e2 with + PEc c1, PEc c2 => PEc (cadd c1 c2) + | PEc c, _ => if ceqb c cO then e2 else PEadd e1 e2 + | _, PEc c => if ceqb c cO then e1 else PEadd e1 e2 + (* Peut t'on factoriser ici ??? *) + | _, _ => PEadd e1 e2 + end. + +Theorem NPEadd_correct: + forall l e1 e2, NPEeval l (NPEadd e1 e2) == NPEeval l (PEadd e1 e2). +Proof. +intros l e1 e2. +destruct e1; destruct e2; simpl in |- *; try reflexivity; try apply ceqb_rect; + try (intro eq_c; rewrite eq_c in |- *); simpl in |- *;try apply eq_refl; + try (ring [(morph0 CRmorph)]). + apply (morph_add CRmorph). +Qed. + +Definition NPEpow x n := + match n with + | N0 => PEc cI + | Npos p => + if positive_eq p xH then x else + match x with + | PEc c => + if ceqb c cI then PEc cI else if ceqb c cO then PEc cO else PEc (pow_pos cmul c p) + | _ => PEpow x n + end + end. + +Theorem NPEpow_correct : forall l e n, + NPEeval l (NPEpow e n) == NPEeval l (PEpow e n). +Proof. + destruct n;simpl. + rewrite pow_th.(rpow_pow_N);simpl;auto. + generalize (positive_eq_correct p xH). + destruct (positive_eq p 1);intros. + rewrite H;rewrite pow_th.(rpow_pow_N). trivial. + clear H;destruct e;simpl;auto. + repeat apply ceqb_rect;simpl;intros;rewrite pow_th.(rpow_pow_N);simpl. + symmetry;induction p;simpl;trivial; ring [IHp H CRmorph.(morph1)]. + symmetry; induction p;simpl;trivial;ring [IHp CRmorph.(morph0)]. + induction p;simpl;auto;repeat rewrite CRmorph.(morph_mul);ring [IHp]. +Qed. + +(* mul *) +Fixpoint NPEmul (x y : PExpr C) {struct x} : PExpr C := + match x, y with + PEc c1, PEc c2 => PEc (cmul c1 c2) + | PEc c, _ => + if ceqb c cI then y else if ceqb c cO then PEc cO else PEmul x y + | _, PEc c => + if ceqb c cI then x else if ceqb c cO then PEc cO else PEmul x y + | PEpow e1 n1, PEpow e2 n2 => + if N_eq n1 n2 then NPEpow (NPEmul e1 e2) n1 else PEmul x y + | _, _ => PEmul x y + end. + +Lemma pow_pos_mul : forall x y p, pow_pos rmul (x * y) p == pow_pos rmul x p * pow_pos rmul y p. +induction p;simpl;auto;try ring [IHp]. +Qed. + +Theorem NPEmul_correct : forall l e1 e2, + NPEeval l (NPEmul e1 e2) == NPEeval l (PEmul e1 e2). +induction e1;destruct e2; simpl in |- *;try reflexivity; + repeat apply ceqb_rect; + try (intro eq_c; rewrite eq_c in |- *); simpl in |- *; try reflexivity; + try ring [(morph0 CRmorph) (morph1 CRmorph)]. + apply (morph_mul CRmorph). +assert (H:=N_eq_correct n n0);destruct (N_eq n n0). +rewrite NPEpow_correct. simpl. +repeat rewrite pow_th.(rpow_pow_N). +rewrite IHe1;rewrite <- H;destruct n;simpl;try ring. +apply pow_pos_mul. +simpl;auto. +Qed. + +(* sub *) +Definition NPEsub e1 e2 := + match e1, e2 with + PEc c1, PEc c2 => PEc (csub c1 c2) + | PEc c, _ => if ceqb c cO then PEopp e2 else PEsub e1 e2 + | _, PEc c => if ceqb c cO then e1 else PEsub e1 e2 + (* Peut-on factoriser ici *) + | _, _ => PEsub e1 e2 + end. + +Theorem NPEsub_correct: + forall l e1 e2, NPEeval l (NPEsub e1 e2) == NPEeval l (PEsub e1 e2). +intros l e1 e2. +destruct e1; destruct e2; simpl in |- *; try reflexivity; try apply ceqb_rect; + try (intro eq_c; rewrite eq_c in |- *); simpl in |- *; + try rewrite (morph0 CRmorph) in |- *; try reflexivity; + try (symmetry; apply rsub_0_l); try (symmetry; apply rsub_0_r). +apply (morph_sub CRmorph). +Qed. + +(* opp *) +Definition NPEopp e1 := + match e1 with PEc c1 => PEc (copp c1) | _ => PEopp e1 end. + +Theorem NPEopp_correct: + forall l e1, NPEeval l (NPEopp e1) == NPEeval l (PEopp e1). +intros l e1; case e1; simpl; auto. +intros; apply (morph_opp CRmorph). +Qed. + +(* simplification *) +Fixpoint PExpr_simp (e : PExpr C) : PExpr C := + match e with + PEadd e1 e2 => NPEadd (PExpr_simp e1) (PExpr_simp e2) + | PEmul e1 e2 => NPEmul (PExpr_simp e1) (PExpr_simp e2) + | PEsub e1 e2 => NPEsub (PExpr_simp e1) (PExpr_simp e2) + | PEopp e1 => NPEopp (PExpr_simp e1) + | PEpow e1 n1 => NPEpow (PExpr_simp e1) n1 + | _ => e + end. + +Theorem PExpr_simp_correct: + forall l e, NPEeval l (PExpr_simp e) == NPEeval l e. +intros l e; elim e; simpl; auto. +intros e1 He1 e2 He2. +transitivity (NPEeval l (PEadd (PExpr_simp e1) (PExpr_simp e2))); auto. +apply NPEadd_correct. +simpl; auto. +intros e1 He1 e2 He2. +transitivity (NPEeval l (PEsub (PExpr_simp e1) (PExpr_simp e2))); auto. +apply NPEsub_correct. +simpl; auto. +intros e1 He1 e2 He2. +transitivity (NPEeval l (PEmul (PExpr_simp e1) (PExpr_simp e2))); auto. +apply NPEmul_correct. +simpl; auto. +intros e1 He1. +transitivity (NPEeval l (PEopp (PExpr_simp e1))); auto. +apply NPEopp_correct. +simpl; auto. +intros e1 He1 n;simpl. +rewrite NPEpow_correct;simpl. +repeat rewrite pow_th.(rpow_pow_N). +rewrite He1;auto. +Qed. + + +(**************************************************************************** + + Datastructure + + ***************************************************************************) + +(* The input: syntax of a field expression *) + +Inductive FExpr : Type := + FEc: C -> FExpr + | FEX: positive -> FExpr + | FEadd: FExpr -> FExpr -> FExpr + | FEsub: FExpr -> FExpr -> FExpr + | FEmul: FExpr -> FExpr -> FExpr + | FEopp: FExpr -> FExpr + | FEinv: FExpr -> FExpr + | FEdiv: FExpr -> FExpr -> FExpr + | FEpow: FExpr -> N -> FExpr . + +Fixpoint FEeval (l : list R) (pe : FExpr) {struct pe} : R := + match pe with + | FEc c => phi c + | FEX x => BinList.nth 0 x l + | FEadd x y => FEeval l x + FEeval l y + | FEsub x y => FEeval l x - FEeval l y + | FEmul x y => FEeval l x * FEeval l y + | FEopp x => - FEeval l x + | FEinv x => / FEeval l x + | FEdiv x y => FEeval l x / FEeval l y + | FEpow x n => rpow (FEeval l x) (Cp_phi n) + end. + +Strategy expand [FEeval]. + +(* The result of the normalisation *) + +Record linear : Type := mk_linear { + num : PExpr C; + denum : PExpr C; + condition : list (PExpr C) }. + +(*************************************************************************** + + Semantics and properties of side condition + + ***************************************************************************) + +Fixpoint PCond (l : list R) (le : list (PExpr C)) {struct le} : Prop := + match le with + | nil => True + | e1 :: nil => ~ req (NPEeval l e1) rO + | e1 :: l1 => ~ req (NPEeval l e1) rO /\ PCond l l1 + end. + +Theorem PCond_cons_inv_l : + forall l a l1, PCond l (a::l1) -> ~ NPEeval l a == 0. +intros l a l1 H. +destruct l1; simpl in H |- *; trivial. +destruct H; trivial. +Qed. + +Theorem PCond_cons_inv_r : forall l a l1, PCond l (a :: l1) -> PCond l l1. +intros l a l1 H. +destruct l1; simpl in H |- *; trivial. +destruct H; trivial. +Qed. + +Theorem PCond_app_inv_l: forall l l1 l2, PCond l (l1 ++ l2) -> PCond l l1. +intros l l1 l2; elim l1; simpl app in |- *. + simpl in |- *; auto. + destruct l0; simpl in *. + destruct l2; firstorder. + firstorder. +Qed. + +Theorem PCond_app_inv_r: forall l l1 l2, PCond l (l1 ++ l2) -> PCond l l2. +intros l l1 l2; elim l1; simpl app; auto. +intros a l0 H H0; apply H; apply PCond_cons_inv_r with ( 1 := H0 ). +Qed. + +(* An unsatisfiable condition: issued when a division by zero is detected *) +Definition absurd_PCond := cons (PEc cO) nil. + +Lemma absurd_PCond_bottom : forall l, ~ PCond l absurd_PCond. +unfold absurd_PCond in |- *; simpl in |- *. +red in |- *; intros. +apply H. +apply (morph0 CRmorph). +Qed. + +(*************************************************************************** + + Normalisation + + ***************************************************************************) + +Fixpoint isIn (e1:PExpr C) (p1:positive) + (e2:PExpr C) (p2:positive) {struct e2}: option (N * PExpr C) := + match e2 with + | PEmul e3 e4 => + match isIn e1 p1 e3 p2 with + | Some (N0, e5) => Some (N0, NPEmul e5 (NPEpow e4 (Npos p2))) + | Some (Npos p, e5) => + match isIn e1 p e4 p2 with + | Some (n, e6) => Some (n, NPEmul e5 e6) + | None => Some (Npos p, NPEmul e5 (NPEpow e4 (Npos p2))) + end + | None => + match isIn e1 p1 e4 p2 with + | Some (n, e5) => Some (n,NPEmul (NPEpow e3 (Npos p2)) e5) + | None => None + end + end + | PEpow e3 N0 => None + | PEpow e3 (Npos p3) => isIn e1 p1 e3 (Pmult p3 p2) + | _ => + if PExpr_eq e1 e2 then + match Zminus (Zpos p1) (Zpos p2) with + | Zpos p => Some (Npos p, PEc cI) + | Z0 => Some (N0, PEc cI) + | Zneg p => Some (N0, NPEpow e2 (Npos p)) + end + else None + end. + + Definition ZtoN z := match z with Zpos p => Npos p | _ => N0 end. + Definition NtoZ n := match n with Npos p => Zpos p | _ => Z0 end. + + Notation pow_pos_plus := (Ring_theory.pow_pos_Pplus _ Rsth Reqe.(Rmul_ext) + ARth.(ARmul_comm) ARth.(ARmul_assoc)). + + Lemma isIn_correct_aux : forall l e1 e2 p1 p2, + match + (if PExpr_eq e1 e2 then + match Zminus (Zpos p1) (Zpos p2) with + | Zpos p => Some (Npos p, PEc cI) + | Z0 => Some (N0, PEc cI) + | Zneg p => Some (N0, NPEpow e2 (Npos p)) + end + else None) + with + | Some(n, e3) => + NPEeval l (PEpow e2 (Npos p2)) == + NPEeval l (PEmul (PEpow e1 (ZtoN (Zpos p1 - NtoZ n))) e3) /\ + (Zpos p1 > NtoZ n)%Z + | _ => True + end. +Proof. + intros l e1 e2 p1 p2; generalize (PExpr_eq_semi_correct l e1 e2); + case (PExpr_eq e1 e2); simpl; auto; intros H. + case_eq ((p1 ?= p2)%positive Eq);intros;simpl. + repeat rewrite pow_th.(rpow_pow_N);simpl. split. 2:refine (refl_equal _). + rewrite (Pcompare_Eq_eq _ _ H0). + rewrite H by trivial. ring [ (morph1 CRmorph)]. + fold (NPEpow e2 (Npos (p2 - p1))). + rewrite NPEpow_correct;simpl. + repeat rewrite pow_th.(rpow_pow_N);simpl. + rewrite H;trivial. split. 2:refine (refl_equal _). + rewrite <- pow_pos_plus; rewrite Pplus_minus;auto. apply ZC2;trivial. + repeat rewrite pow_th.(rpow_pow_N);simpl. + rewrite H;trivial. + change (ZtoN + match (p1 ?= p1 - p2)%positive Eq with + | Eq => 0 + | Lt => Zneg (p1 - p2 - p1) + | Gt => Zpos (p1 - (p1 - p2)) + end) with (ZtoN (Zpos p1 - Zpos (p1 -p2))). + replace (Zpos (p1 - p2)) with (Zpos p1 - Zpos p2)%Z. + split. + repeat rewrite Zth.(Rsub_def). rewrite (Ring_theory.Ropp_add Zsth Zeqe Zth). + rewrite Zplus_assoc. simpl. rewrite Pcompare_refl. simpl. + ring [ (morph1 CRmorph)]. + assert (Zpos p1 > 0 /\ Zpos p2 > 0)%Z. split;refine (refl_equal _). + apply Zplus_gt_reg_l with (Zpos p2). + rewrite Zplus_minus. change (Zpos p2 + Zpos p1 > 0 + Zpos p1)%Z. + apply Zplus_gt_compat_r. refine (refl_equal _). + simpl;rewrite H0;trivial. +Qed. + +Lemma pow_pos_pow_pos : forall x p1 p2, pow_pos rmul (pow_pos rmul x p1) p2 == pow_pos rmul x (p1*p2). +induction p1;simpl;intros;repeat rewrite pow_pos_mul;repeat rewrite pow_pos_plus;simpl. +ring [(IHp1 p2)]. ring [(IHp1 p2)]. auto. +Qed. + + +Theorem isIn_correct: forall l e1 p1 e2 p2, + match isIn e1 p1 e2 p2 with + | Some(n, e3) => + NPEeval l (PEpow e2 (Npos p2)) == + NPEeval l (PEmul (PEpow e1 (ZtoN (Zpos p1 - NtoZ n))) e3) /\ + (Zpos p1 > NtoZ n)%Z + | _ => True + end. +Proof. +Opaque NPEpow. +intros l e1 p1 e2; generalize p1;clear p1;elim e2; intros; + try (refine (isIn_correct_aux l e1 _ p1 p2);fail);simpl isIn. +generalize (H p1 p2);clear H;destruct (isIn e1 p1 p p2). destruct p3. +destruct n. + simpl. rewrite NPEmul_correct. simpl; rewrite NPEpow_correct;simpl. + repeat rewrite pow_th.(rpow_pow_N);simpl. + rewrite pow_pos_mul;intros (H,H1);split;[ring[H]|trivial]. + generalize (H0 p4 p2);clear H0;destruct (isIn e1 p4 p0 p2). destruct p5. + destruct n;simpl. + rewrite NPEmul_correct;repeat rewrite pow_th.(rpow_pow_N);simpl. + intros (H1,H2) (H3,H4). + unfold Zgt in H2, H4;simpl in H2,H4. rewrite H4 in H3;simpl in H3. + rewrite pow_pos_mul. rewrite H1;rewrite H3. + assert (pow_pos rmul (NPEeval l e1) (p1 - p4) * NPEeval l p3 * + (pow_pos rmul (NPEeval l e1) p4 * NPEeval l p5) == + pow_pos rmul (NPEeval l e1) p4 * pow_pos rmul (NPEeval l e1) (p1 - p4) * + NPEeval l p3 *NPEeval l p5) by ring. rewrite H;clear H. + rewrite <- pow_pos_plus. rewrite Pplus_minus. + split. symmetry;apply ARth.(ARmul_assoc). refine (refl_equal _). trivial. + repeat rewrite pow_th.(rpow_pow_N);simpl. + intros (H1,H2) (H3,H4). + unfold Zgt in H2, H4;simpl in H2,H4. rewrite H4 in H3;simpl in H3. + rewrite H2 in H1;simpl in H1. + assert (Zpos p1 > Zpos p6)%Z. + apply Zgt_trans with (Zpos p4). exact H4. exact H2. + unfold Zgt in H;simpl in H;rewrite H. + split. 2:exact H. + rewrite pow_pos_mul. simpl;rewrite H1;rewrite H3. + assert (pow_pos rmul (NPEeval l e1) (p1 - p4) * NPEeval l p3 * + (pow_pos rmul (NPEeval l e1) (p4 - p6) * NPEeval l p5) == + pow_pos rmul (NPEeval l e1) (p1 - p4) * pow_pos rmul (NPEeval l e1) (p4 - p6) * + NPEeval l p3 * NPEeval l p5) by ring. rewrite H0;clear H0. + rewrite <- pow_pos_plus. + replace (p1 - p4 + (p4 - p6))%positive with (p1 - p6)%positive. + rewrite NPEmul_correct. simpl;ring. + assert + (Zpos p1 - Zpos p6 = Zpos p1 - Zpos p4 + (Zpos p4 - Zpos p6))%Z. + change ((Zpos p1 - Zpos p6)%Z = (Zpos p1 + (- Zpos p4) + (Zpos p4 +(- Zpos p6)))%Z). + rewrite <- Zplus_assoc. rewrite (Zplus_assoc (- Zpos p4)). + simpl. rewrite Pcompare_refl. simpl. reflexivity. + unfold Zminus, Zopp in H0. simpl in H0. + rewrite H2 in H0;rewrite H4 in H0;rewrite H in H0. inversion H0;trivial. + simpl. repeat rewrite pow_th.(rpow_pow_N). + intros H1 (H2,H3). unfold Zgt in H3;simpl in H3. rewrite H3 in H2;rewrite H3. + rewrite NPEmul_correct;simpl;rewrite NPEpow_correct;simpl. + simpl in H2. rewrite pow_th.(rpow_pow_N);simpl. + rewrite pow_pos_mul. split. ring [H2]. exact H3. + generalize (H0 p1 p2);clear H0;destruct (isIn e1 p1 p0 p2). destruct p3. + destruct n;simpl. rewrite NPEmul_correct;simpl;rewrite NPEpow_correct;simpl. + repeat rewrite pow_th.(rpow_pow_N);simpl. + intros (H1,H2);split;trivial. rewrite pow_pos_mul;ring [H1]. + rewrite NPEmul_correct;simpl;rewrite NPEpow_correct;simpl. + repeat rewrite pow_th.(rpow_pow_N);simpl. rewrite pow_pos_mul. + intros (H1, H2);rewrite H1;split. + unfold Zgt in H2;simpl in H2;rewrite H2;rewrite H2 in H1. + simpl in H1;ring [H1]. trivial. + trivial. + destruct n. trivial. + generalize (H p1 (p0*p2)%positive);clear H;destruct (isIn e1 p1 p (p0*p2)). destruct p3. + destruct n;simpl. repeat rewrite pow_th.(rpow_pow_N). simpl. + intros (H1,H2);split. rewrite pow_pos_pow_pos. trivial. trivial. + repeat rewrite pow_th.(rpow_pow_N). simpl. + intros (H1,H2);split;trivial. + rewrite pow_pos_pow_pos;trivial. + trivial. +Qed. + +Record rsplit : Type := mk_rsplit { + rsplit_left : PExpr C; + rsplit_common : PExpr C; + rsplit_right : PExpr C}. + +(* Stupid name clash *) +Notation left := rsplit_left. +Notation right := rsplit_right. +Notation common := rsplit_common. + +Fixpoint split_aux (e1: PExpr C) (p:positive) (e2:PExpr C) {struct e1}: rsplit := + match e1 with + | PEmul e3 e4 => + let r1 := split_aux e3 p e2 in + let r2 := split_aux e4 p (right r1) in + mk_rsplit (NPEmul (left r1) (left r2)) + (NPEmul (common r1) (common r2)) + (right r2) + | PEpow e3 N0 => mk_rsplit (PEc cI) (PEc cI) e2 + | PEpow e3 (Npos p3) => split_aux e3 (Pmult p3 p) e2 + | _ => + match isIn e1 p e2 xH with + | Some (N0,e3) => mk_rsplit (PEc cI) (NPEpow e1 (Npos p)) e3 + | Some (Npos q, e3) => mk_rsplit (NPEpow e1 (Npos q)) (NPEpow e1 (Npos (p - q))) e3 + | None => mk_rsplit (NPEpow e1 (Npos p)) (PEc cI) e2 + end + end. + +Lemma split_aux_correct_1 : forall l e1 p e2, + let res := match isIn e1 p e2 xH with + | Some (N0,e3) => mk_rsplit (PEc cI) (NPEpow e1 (Npos p)) e3 + | Some (Npos q, e3) => mk_rsplit (NPEpow e1 (Npos q)) (NPEpow e1 (Npos (p - q))) e3 + | None => mk_rsplit (NPEpow e1 (Npos p)) (PEc cI) e2 + end in + NPEeval l (PEpow e1 (Npos p)) == NPEeval l (NPEmul (left res) (common res)) + /\ + NPEeval l e2 == NPEeval l (NPEmul (right res) (common res)). +Proof. + intros. unfold res;clear res; generalize (isIn_correct l e1 p e2 xH). + destruct (isIn e1 p e2 1). destruct p0. + Opaque NPEpow NPEmul. + destruct n;simpl; + (repeat rewrite NPEmul_correct;simpl; + repeat rewrite NPEpow_correct;simpl; + repeat rewrite pow_th.(rpow_pow_N);simpl). + intros (H, Hgt);split;try ring [H CRmorph.(morph1)]. + intros (H, Hgt). unfold Zgt in Hgt;simpl in Hgt;rewrite Hgt in H. + simpl in H;split;try ring [H]. + rewrite <- pow_pos_plus. rewrite Pplus_minus. reflexivity. trivial. + simpl;intros. repeat rewrite NPEmul_correct;simpl. + rewrite NPEpow_correct;simpl. split;ring [CRmorph.(morph1)]. +Qed. + +Theorem split_aux_correct: forall l e1 p e2, + NPEeval l (PEpow e1 (Npos p)) == + NPEeval l (NPEmul (left (split_aux e1 p e2)) (common (split_aux e1 p e2))) +/\ + NPEeval l e2 == NPEeval l (NPEmul (right (split_aux e1 p e2)) + (common (split_aux e1 p e2))). +Proof. +intros l; induction e1;intros k e2; try refine (split_aux_correct_1 l _ k e2);simpl. +generalize (IHe1_1 k e2); clear IHe1_1. +generalize (IHe1_2 k (rsplit_right (split_aux e1_1 k e2))); clear IHe1_2. +simpl. repeat (rewrite NPEmul_correct;simpl). +repeat rewrite pow_th.(rpow_pow_N);simpl. +intros (H1,H2) (H3,H4);split. +rewrite pow_pos_mul. rewrite H1;rewrite H3. ring. +rewrite H4;rewrite H2;ring. +destruct n;simpl. +split. repeat rewrite pow_th.(rpow_pow_N);simpl. +rewrite NPEmul_correct. simpl. + induction k;simpl;try ring [CRmorph.(morph1)]; ring [IHk CRmorph.(morph1)]. + rewrite NPEmul_correct;simpl. ring [CRmorph.(morph1)]. +generalize (IHe1 (p*k)%positive e2);clear IHe1;simpl. +repeat rewrite NPEmul_correct;simpl. +repeat rewrite pow_th.(rpow_pow_N);simpl. +rewrite pow_pos_pow_pos. intros [H1 H2];split;ring [H1 H2]. +Qed. + +Definition split e1 e2 := split_aux e1 xH e2. + +Theorem split_correct_l: forall l e1 e2, + NPEeval l e1 == NPEeval l (NPEmul (left (split e1 e2)) + (common (split e1 e2))). +Proof. +intros l e1 e2; case (split_aux_correct l e1 xH e2);simpl. +rewrite pow_th.(rpow_pow_N);simpl;auto. +Qed. + +Theorem split_correct_r: forall l e1 e2, + NPEeval l e2 == NPEeval l (NPEmul (right (split e1 e2)) + (common (split e1 e2))). +Proof. +intros l e1 e2; case (split_aux_correct l e1 xH e2);simpl;auto. +Qed. + +Fixpoint Fnorm (e : FExpr) : linear := + match e with + | FEc c => mk_linear (PEc c) (PEc cI) nil + | FEX x => mk_linear (PEX C x) (PEc cI) nil + | FEadd e1 e2 => + let x := Fnorm e1 in + let y := Fnorm e2 in + let s := split (denum x) (denum y) in + mk_linear + (NPEadd (NPEmul (num x) (right s)) (NPEmul (num y) (left s))) + (NPEmul (left s) (NPEmul (right s) (common s))) + (condition x ++ condition y) + + | FEsub e1 e2 => + let x := Fnorm e1 in + let y := Fnorm e2 in + let s := split (denum x) (denum y) in + mk_linear + (NPEsub (NPEmul (num x) (right s)) (NPEmul (num y) (left s))) + (NPEmul (left s) (NPEmul (right s) (common s))) + (condition x ++ condition y) + | FEmul e1 e2 => + let x := Fnorm e1 in + let y := Fnorm e2 in + let s1 := split (num x) (denum y) in + let s2 := split (num y) (denum x) in + mk_linear (NPEmul (left s1) (left s2)) + (NPEmul (right s2) (right s1)) + (condition x ++ condition y) + | FEopp e1 => + let x := Fnorm e1 in + mk_linear (NPEopp (num x)) (denum x) (condition x) + | FEinv e1 => + let x := Fnorm e1 in + mk_linear (denum x) (num x) (num x :: condition x) + | FEdiv e1 e2 => + let x := Fnorm e1 in + let y := Fnorm e2 in + let s1 := split (num x) (num y) in + let s2 := split (denum x) (denum y) in + mk_linear (NPEmul (left s1) (right s2)) + (NPEmul (left s2) (right s1)) + (num y :: condition x ++ condition y) + | FEpow e1 n => + let x := Fnorm e1 in + mk_linear (NPEpow (num x) n) (NPEpow (denum x) n) (condition x) + end. + + +(* Example *) +(* +Eval compute + in (Fnorm + (FEdiv + (FEc cI) + (FEadd (FEinv (FEX xH%positive)) (FEinv (FEX (xO xH)%positive))))). +*) + + Lemma pow_pos_not_0 : forall x, ~x==0 -> forall p, ~pow_pos rmul x p == 0. +Proof. + induction p;simpl. + intro Hp;assert (H1 := @rmul_reg_l _ (pow_pos rmul x p * pow_pos rmul x p) 0 H). + apply IHp. + rewrite (@rmul_reg_l _ (pow_pos rmul x p) 0 IHp). + reflexivity. + rewrite H1. ring. rewrite Hp;ring. + intro Hp;apply IHp. rewrite (@rmul_reg_l _ (pow_pos rmul x p) 0 IHp). + reflexivity. rewrite Hp;ring. trivial. +Qed. + +Theorem Pcond_Fnorm: + forall l e, + PCond l (condition (Fnorm e)) -> ~ NPEeval l (denum (Fnorm e)) == 0. +intros l e; elim e. + simpl in |- *; intros _ _; rewrite (morph1 CRmorph) in |- *; exact rI_neq_rO. + simpl in |- *; intros _ _; rewrite (morph1 CRmorph) in |- *; exact rI_neq_rO. + intros e1 Hrec1 e2 Hrec2 Hcond. + simpl condition in Hcond. + simpl denum in |- *. + rewrite NPEmul_correct in |- *. + simpl in |- *. + apply field_is_integral_domain. + intros HH; case Hrec1; auto. + apply PCond_app_inv_l with (1 := Hcond). + rewrite (split_correct_l l (denum (Fnorm e1)) (denum (Fnorm e2))). + rewrite NPEmul_correct; simpl; rewrite HH; ring. + intros HH; case Hrec2; auto. + apply PCond_app_inv_r with (1 := Hcond). + rewrite (split_correct_r l (denum (Fnorm e1)) (denum (Fnorm e2))); auto. + intros e1 Hrec1 e2 Hrec2 Hcond. + simpl condition in Hcond. + simpl denum in |- *. + rewrite NPEmul_correct in |- *. + simpl in |- *. + apply field_is_integral_domain. + intros HH; case Hrec1; auto. + apply PCond_app_inv_l with (1 := Hcond). + rewrite (split_correct_l l (denum (Fnorm e1)) (denum (Fnorm e2))). + rewrite NPEmul_correct; simpl; rewrite HH; ring. + intros HH; case Hrec2; auto. + apply PCond_app_inv_r with (1 := Hcond). + rewrite (split_correct_r l (denum (Fnorm e1)) (denum (Fnorm e2))); auto. + intros e1 Hrec1 e2 Hrec2 Hcond. + simpl condition in Hcond. + simpl denum in |- *. + rewrite NPEmul_correct in |- *. + simpl in |- *. + apply field_is_integral_domain. + intros HH; apply Hrec1. + apply PCond_app_inv_l with (1 := Hcond). + rewrite (split_correct_r l (num (Fnorm e2)) (denum (Fnorm e1))). + rewrite NPEmul_correct; simpl; rewrite HH; ring. + intros HH; apply Hrec2. + apply PCond_app_inv_r with (1 := Hcond). + rewrite (split_correct_r l (num (Fnorm e1)) (denum (Fnorm e2))). + rewrite NPEmul_correct; simpl; rewrite HH; ring. + intros e1 Hrec1 Hcond. + simpl condition in Hcond. + simpl denum in |- *. + auto. + intros e1 Hrec1 Hcond. + simpl condition in Hcond. + simpl denum in |- *. + apply PCond_cons_inv_l with (1:=Hcond). + intros e1 Hrec1 e2 Hrec2 Hcond. + simpl condition in Hcond. + simpl denum in |- *. + rewrite NPEmul_correct in |- *. + simpl in |- *. + apply field_is_integral_domain. + intros HH; apply Hrec1. + specialize PCond_cons_inv_r with (1:=Hcond); intro Hcond1. + apply PCond_app_inv_l with (1 := Hcond1). + rewrite (split_correct_l l (denum (Fnorm e1)) (denum (Fnorm e2))). + rewrite NPEmul_correct; simpl; rewrite HH; ring. + intros HH; apply PCond_cons_inv_l with (1:=Hcond). + rewrite (split_correct_r l (num (Fnorm e1)) (num (Fnorm e2))). + rewrite NPEmul_correct; simpl; rewrite HH; ring. + simpl;intros e1 Hrec1 n Hcond. + rewrite NPEpow_correct. + simpl;rewrite pow_th.(rpow_pow_N). + destruct n;simpl;intros. + apply AFth.(AF_1_neq_0). apply pow_pos_not_0;auto. +Qed. +Hint Resolve Pcond_Fnorm. + + +(*************************************************************************** + + Main theorem + + ***************************************************************************) + +Theorem Fnorm_FEeval_PEeval: + forall l fe, + PCond l (condition (Fnorm fe)) -> + FEeval l fe == NPEeval l (num (Fnorm fe)) / NPEeval l (denum (Fnorm fe)). +Proof. +intros l fe; elim fe; simpl. +intros c H; rewrite CRmorph.(morph1); apply rdiv1. +intros p H; rewrite CRmorph.(morph1); apply rdiv1. +intros e1 He1 e2 He2 HH. +assert (HH1: PCond l (condition (Fnorm e1))). +apply PCond_app_inv_l with ( 1 := HH ). +assert (HH2: PCond l (condition (Fnorm e2))). +apply PCond_app_inv_r with ( 1 := HH ). +rewrite (He1 HH1); rewrite (He2 HH2). +rewrite NPEadd_correct; simpl. +repeat rewrite NPEmul_correct; simpl. +generalize (split_correct_l l (denum (Fnorm e1)) (denum (Fnorm e2))) + (split_correct_r l (denum (Fnorm e1)) (denum (Fnorm e2))). +repeat rewrite NPEmul_correct; simpl. +intros U1 U2; rewrite U1; rewrite U2. +apply rdiv2b; auto. + rewrite <- U1; auto. + rewrite <- U2; auto. + +intros e1 He1 e2 He2 HH. +assert (HH1: PCond l (condition (Fnorm e1))). +apply PCond_app_inv_l with ( 1 := HH ). +assert (HH2: PCond l (condition (Fnorm e2))). +apply PCond_app_inv_r with ( 1 := HH ). +rewrite (He1 HH1); rewrite (He2 HH2). +rewrite NPEsub_correct; simpl. +repeat rewrite NPEmul_correct; simpl. +generalize (split_correct_l l (denum (Fnorm e1)) (denum (Fnorm e2))) + (split_correct_r l (denum (Fnorm e1)) (denum (Fnorm e2))). +repeat rewrite NPEmul_correct; simpl. +intros U1 U2; rewrite U1; rewrite U2. +apply rdiv3b; auto. + rewrite <- U1; auto. + rewrite <- U2; auto. + +intros e1 He1 e2 He2 HH. +assert (HH1: PCond l (condition (Fnorm e1))). +apply PCond_app_inv_l with ( 1 := HH ). +assert (HH2: PCond l (condition (Fnorm e2))). +apply PCond_app_inv_r with ( 1 := HH ). +rewrite (He1 HH1); rewrite (He2 HH2). +repeat rewrite NPEmul_correct; simpl. +generalize (split_correct_l l (num (Fnorm e1)) (denum (Fnorm e2))) + (split_correct_r l (num (Fnorm e1)) (denum (Fnorm e2))) + (split_correct_l l (num (Fnorm e2)) (denum (Fnorm e1))) + (split_correct_r l (num (Fnorm e2)) (denum (Fnorm e1))). +repeat rewrite NPEmul_correct; simpl. +intros U1 U2 U3 U4; rewrite U1; rewrite U2; rewrite U3; + rewrite U4; simpl. +apply rdiv4b; auto. + rewrite <- U4; auto. + rewrite <- U2; auto. + +intros e1 He1 HH. +rewrite NPEopp_correct; simpl; rewrite (He1 HH); apply rdiv5; auto. + +intros e1 He1 HH. +assert (HH1: PCond l (condition (Fnorm e1))). +apply PCond_cons_inv_r with ( 1 := HH ). +rewrite (He1 HH1); apply rdiv6; auto. +apply PCond_cons_inv_l with ( 1 := HH ). + +intros e1 He1 e2 He2 HH. +assert (HH1: PCond l (condition (Fnorm e1))). +apply PCond_app_inv_l with (condition (Fnorm e2)). +apply PCond_cons_inv_r with ( 1 := HH ). +assert (HH2: PCond l (condition (Fnorm e2))). +apply PCond_app_inv_r with (condition (Fnorm e1)). +apply PCond_cons_inv_r with ( 1 := HH ). +rewrite (He1 HH1); rewrite (He2 HH2). +repeat rewrite NPEmul_correct;simpl. +generalize (split_correct_l l (num (Fnorm e1)) (num (Fnorm e2))) + (split_correct_r l (num (Fnorm e1)) (num (Fnorm e2))) + (split_correct_l l (denum (Fnorm e1)) (denum (Fnorm e2))) + (split_correct_r l (denum (Fnorm e1)) (denum (Fnorm e2))). +repeat rewrite NPEmul_correct; simpl. +intros U1 U2 U3 U4; rewrite U1; rewrite U2; rewrite U3; + rewrite U4; simpl. +apply rdiv7b; auto. + rewrite <- U3; auto. + rewrite <- U2; auto. +apply PCond_cons_inv_l with ( 1 := HH ). + rewrite <- U4; auto. + +intros e1 He1 n Hcond;assert (He1' := He1 Hcond);clear He1. +repeat rewrite NPEpow_correct;simpl;repeat rewrite pow_th.(rpow_pow_N). +rewrite He1';clear He1'. +destruct n;simpl. apply rdiv1. +generalize (NPEeval l (num (Fnorm e1))) (NPEeval l (denum (Fnorm e1))) + (Pcond_Fnorm _ _ Hcond). +intros r r0 Hdiff;induction p;simpl. +repeat (rewrite <- rdiv4;trivial). +rewrite IHp. reflexivity. +apply pow_pos_not_0;trivial. +apply pow_pos_not_0;trivial. +intro Hp. apply (pow_pos_not_0 Hdiff p). +rewrite (@rmul_reg_l (pow_pos rmul r0 p) (pow_pos rmul r0 p) 0). + reflexivity. apply pow_pos_not_0;trivial. ring [Hp]. +rewrite <- rdiv4;trivial. +rewrite IHp;reflexivity. +apply pow_pos_not_0;trivial. apply pow_pos_not_0;trivial. +reflexivity. +Qed. + +Theorem Fnorm_crossproduct: + forall l fe1 fe2, + let nfe1 := Fnorm fe1 in + let nfe2 := Fnorm fe2 in + NPEeval l (PEmul (num nfe1) (denum nfe2)) == + NPEeval l (PEmul (num nfe2) (denum nfe1)) -> + PCond l (condition nfe1 ++ condition nfe2) -> + FEeval l fe1 == FEeval l fe2. +intros l fe1 fe2 nfe1 nfe2 Hcrossprod Hcond; subst nfe1 nfe2. +rewrite Fnorm_FEeval_PEeval in |- * by + apply PCond_app_inv_l with (1 := Hcond). + rewrite Fnorm_FEeval_PEeval in |- * by + apply PCond_app_inv_r with (1 := Hcond). + apply cross_product_eq; trivial. + apply Pcond_Fnorm. + apply PCond_app_inv_l with (1 := Hcond). + apply Pcond_Fnorm. + apply PCond_app_inv_r with (1 := Hcond). +Qed. + +(* Correctness lemmas of reflexive tactics *) +Notation Ninterp_PElist := (interp_PElist rO radd rmul rsub ropp req phi Cp_phi rpow). +Notation Nmk_monpol_list := (mk_monpol_list cO cI cadd cmul csub copp ceqb cdiv). + +Theorem Fnorm_correct: + forall n l lpe fe, + Ninterp_PElist l lpe -> + Peq ceqb (Nnorm n (Nmk_monpol_list lpe) (num (Fnorm fe))) (Pc cO) = true -> + PCond l (condition (Fnorm fe)) -> FEeval l fe == 0. +intros n l lpe fe Hlpe H H1; + apply eq_trans with (1 := Fnorm_FEeval_PEeval l fe H1). +apply rdiv8; auto. +transitivity (NPEeval l (PEc cO)); auto. +rewrite (norm_subst_ok Rsth Reqe ARth CRmorph pow_th cdiv_th n l lpe);auto. +change (NPEeval l (PEc cO)) with (Pphi 0 radd rmul phi l (Pc cO)). +apply (Peq_ok Rsth Reqe CRmorph);auto. +simpl. apply (morph0 CRmorph); auto. +Qed. + +(* simplify a field expression into a fraction *) +(* TODO: simplify when den is constant... *) +Definition display_linear l num den := + NPphi_dev l num / NPphi_dev l den. + +Definition display_pow_linear l num den := + NPphi_pow l num / NPphi_pow l den. + +Theorem Field_rw_correct : + forall n lpe l, + Ninterp_PElist l lpe -> + forall lmp, Nmk_monpol_list lpe = lmp -> + forall fe nfe, Fnorm fe = nfe -> + PCond l (condition nfe) -> + FEeval l fe == display_linear l (Nnorm n lmp (num nfe)) (Nnorm n lmp (denum nfe)). +Proof. + intros n lpe l Hlpe lmp lmp_eq fe nfe eq_nfe H; subst nfe lmp. + apply eq_trans with (1 := Fnorm_FEeval_PEeval _ _ H). + unfold display_linear; apply SRdiv_ext; + eapply (ring_rw_correct Rsth Reqe ARth CRmorph);eauto. +Qed. + +Theorem Field_rw_pow_correct : + forall n lpe l, + Ninterp_PElist l lpe -> + forall lmp, Nmk_monpol_list lpe = lmp -> + forall fe nfe, Fnorm fe = nfe -> + PCond l (condition nfe) -> + FEeval l fe == display_pow_linear l (Nnorm n lmp (num nfe)) (Nnorm n lmp (denum nfe)). +Proof. + intros n lpe l Hlpe lmp lmp_eq fe nfe eq_nfe H; subst nfe lmp. + apply eq_trans with (1 := Fnorm_FEeval_PEeval _ _ H). + unfold display_pow_linear; apply SRdiv_ext; + eapply (ring_rw_pow_correct Rsth Reqe ARth CRmorph);eauto. +Qed. + +Theorem Field_correct : + forall n l lpe fe1 fe2, Ninterp_PElist l lpe -> + forall lmp, Nmk_monpol_list lpe = lmp -> + forall nfe1, Fnorm fe1 = nfe1 -> + forall nfe2, Fnorm fe2 = nfe2 -> + Peq ceqb (Nnorm n lmp (PEmul (num nfe1) (denum nfe2))) + (Nnorm n lmp (PEmul (num nfe2) (denum nfe1))) = true -> + PCond l (condition nfe1 ++ condition nfe2) -> + FEeval l fe1 == FEeval l fe2. +Proof. +intros n l lpe fe1 fe2 Hlpe lmp eq_lmp nfe1 eq1 nfe2 eq2 Hnorm Hcond; subst nfe1 nfe2 lmp. +apply Fnorm_crossproduct; trivial. +eapply (ring_correct Rsth Reqe ARth CRmorph); eauto. +Qed. + +(* simplify a field equation : generate the crossproduct and simplify + polynomials *) +Theorem Field_simplify_eq_old_correct : + forall l fe1 fe2 nfe1 nfe2, + Fnorm fe1 = nfe1 -> + Fnorm fe2 = nfe2 -> + NPphi_dev l (Nnorm O nil (PEmul (num nfe1) (denum nfe2))) == + NPphi_dev l (Nnorm O nil (PEmul (num nfe2) (denum nfe1))) -> + PCond l (condition nfe1 ++ condition nfe2) -> + FEeval l fe1 == FEeval l fe2. +Proof. +intros l fe1 fe2 nfe1 nfe2 eq1 eq2 Hcrossprod Hcond; subst nfe1 nfe2. +apply Fnorm_crossproduct; trivial. +match goal with + [ |- NPEeval l ?x == NPEeval l ?y] => + rewrite (ring_rw_correct Rsth Reqe ARth CRmorph pow_th cdiv_th get_sign_spec + O nil l I (refl_equal nil) x (refl_equal (Nnorm O nil x))); + rewrite (ring_rw_correct Rsth Reqe ARth CRmorph pow_th cdiv_th get_sign_spec + O nil l I (refl_equal nil) y (refl_equal (Nnorm O nil y))) + end. +trivial. +Qed. + +Theorem Field_simplify_eq_correct : + forall n l lpe fe1 fe2, + Ninterp_PElist l lpe -> + forall lmp, Nmk_monpol_list lpe = lmp -> + forall nfe1, Fnorm fe1 = nfe1 -> + forall nfe2, Fnorm fe2 = nfe2 -> + forall den, split (denum nfe1) (denum nfe2) = den -> + NPphi_dev l (Nnorm n lmp (PEmul (num nfe1) (right den))) == + NPphi_dev l (Nnorm n lmp (PEmul (num nfe2) (left den))) -> + PCond l (condition nfe1 ++ condition nfe2) -> + FEeval l fe1 == FEeval l fe2. +Proof. +intros n l lpe fe1 fe2 Hlpe lmp Hlmp nfe1 eq1 nfe2 eq2 den eq3 Hcrossprod Hcond; + subst nfe1 nfe2 den lmp. +apply Fnorm_crossproduct; trivial. +simpl in |- *. +rewrite (split_correct_l l (denum (Fnorm fe1)) (denum (Fnorm fe2))) in |- *. +rewrite (split_correct_r l (denum (Fnorm fe1)) (denum (Fnorm fe2))) in |- *. +rewrite NPEmul_correct in |- *. +rewrite NPEmul_correct in |- *. +simpl in |- *. +repeat rewrite (ARmul_assoc ARth) in |- *. +rewrite <-( + let x := PEmul (num (Fnorm fe1)) + (rsplit_right (split (denum (Fnorm fe1)) (denum (Fnorm fe2)))) in +ring_rw_correct Rsth Reqe ARth CRmorph pow_th cdiv_th get_sign_spec n lpe l + Hlpe (refl_equal (Nmk_monpol_list lpe)) + x (refl_equal (Nnorm n (Nmk_monpol_list lpe) x))) in Hcrossprod. +rewrite <-( + let x := (PEmul (num (Fnorm fe2)) + (rsplit_left + (split (denum (Fnorm fe1)) (denum (Fnorm fe2))))) in + ring_rw_correct Rsth Reqe ARth CRmorph pow_th cdiv_th get_sign_spec n lpe l + Hlpe (refl_equal (Nmk_monpol_list lpe)) + x (refl_equal (Nnorm n (Nmk_monpol_list lpe) x))) in Hcrossprod. +simpl in Hcrossprod. +rewrite Hcrossprod in |- *. +reflexivity. +Qed. + +Theorem Field_simplify_eq_pow_correct : + forall n l lpe fe1 fe2, + Ninterp_PElist l lpe -> + forall lmp, Nmk_monpol_list lpe = lmp -> + forall nfe1, Fnorm fe1 = nfe1 -> + forall nfe2, Fnorm fe2 = nfe2 -> + forall den, split (denum nfe1) (denum nfe2) = den -> + NPphi_pow l (Nnorm n lmp (PEmul (num nfe1) (right den))) == + NPphi_pow l (Nnorm n lmp (PEmul (num nfe2) (left den))) -> + PCond l (condition nfe1 ++ condition nfe2) -> + FEeval l fe1 == FEeval l fe2. +Proof. +intros n l lpe fe1 fe2 Hlpe lmp Hlmp nfe1 eq1 nfe2 eq2 den eq3 Hcrossprod Hcond; + subst nfe1 nfe2 den lmp. +apply Fnorm_crossproduct; trivial. +simpl in |- *. +rewrite (split_correct_l l (denum (Fnorm fe1)) (denum (Fnorm fe2))) in |- *. +rewrite (split_correct_r l (denum (Fnorm fe1)) (denum (Fnorm fe2))) in |- *. +rewrite NPEmul_correct in |- *. +rewrite NPEmul_correct in |- *. +simpl in |- *. +repeat rewrite (ARmul_assoc ARth) in |- *. +rewrite <-( + let x := PEmul (num (Fnorm fe1)) + (rsplit_right (split (denum (Fnorm fe1)) (denum (Fnorm fe2)))) in +ring_rw_pow_correct Rsth Reqe ARth CRmorph pow_th cdiv_th get_sign_spec n lpe l + Hlpe (refl_equal (Nmk_monpol_list lpe)) + x (refl_equal (Nnorm n (Nmk_monpol_list lpe) x))) in Hcrossprod. +rewrite <-( + let x := (PEmul (num (Fnorm fe2)) + (rsplit_left + (split (denum (Fnorm fe1)) (denum (Fnorm fe2))))) in + ring_rw_pow_correct Rsth Reqe ARth CRmorph pow_th cdiv_th get_sign_spec n lpe l + Hlpe (refl_equal (Nmk_monpol_list lpe)) + x (refl_equal (Nnorm n (Nmk_monpol_list lpe) x))) in Hcrossprod. +simpl in Hcrossprod. +rewrite Hcrossprod in |- *. +reflexivity. +Qed. + +Theorem Field_simplify_eq_pow_in_correct : + forall n l lpe fe1 fe2, + Ninterp_PElist l lpe -> + forall lmp, Nmk_monpol_list lpe = lmp -> + forall nfe1, Fnorm fe1 = nfe1 -> + forall nfe2, Fnorm fe2 = nfe2 -> + forall den, split (denum nfe1) (denum nfe2) = den -> + forall np1, Nnorm n lmp (PEmul (num nfe1) (right den)) = np1 -> + forall np2, Nnorm n lmp (PEmul (num nfe2) (left den)) = np2 -> + FEeval l fe1 == FEeval l fe2 -> + PCond l (condition nfe1 ++ condition nfe2) -> + NPphi_pow l np1 == + NPphi_pow l np2. +Proof. + intros. subst nfe1 nfe2 lmp np1 np2. + repeat rewrite (Pphi_pow_ok Rsth Reqe ARth CRmorph pow_th get_sign_spec). + repeat (rewrite <- (norm_subst_ok Rsth Reqe ARth CRmorph pow_th);trivial). simpl. + assert (N1 := Pcond_Fnorm _ _ (PCond_app_inv_l _ _ _ H7)). + assert (N2 := Pcond_Fnorm _ _ (PCond_app_inv_r _ _ _ H7)). + apply (@rmul_reg_l (NPEeval l (rsplit_common den))). + intro Heq;apply N1. + rewrite (split_correct_l l (denum (Fnorm fe1)) (denum (Fnorm fe2))). + rewrite H3. rewrite NPEmul_correct. simpl. ring [Heq]. + repeat rewrite (ARth.(ARmul_comm) (NPEeval l (rsplit_common den))). + repeat rewrite <- ARth.(ARmul_assoc). + change (NPEeval l (rsplit_right den) * NPEeval l (rsplit_common den)) with + (NPEeval l (PEmul (rsplit_right den) (rsplit_common den))). + change (NPEeval l (rsplit_left den) * NPEeval l (rsplit_common den)) with + (NPEeval l (PEmul (rsplit_left den) (rsplit_common den))). + repeat rewrite <- NPEmul_correct. rewrite <- H3. rewrite <- split_correct_l. + rewrite <- split_correct_r. + apply (@rmul_reg_l (/NPEeval l (denum (Fnorm fe2)))). + intro Heq; apply AFth.(AF_1_neq_0). + rewrite <- (@AFinv_l AFth (NPEeval l (denum (Fnorm fe2))));trivial. + ring [Heq]. rewrite (ARth.(ARmul_comm) (/ NPEeval l (denum (Fnorm fe2)))). + repeat rewrite <- (ARth.(ARmul_assoc)). + rewrite <- (AFth.(AFdiv_def)). rewrite rdiv_r_r by trivial. + apply (@rmul_reg_l (/NPEeval l (denum (Fnorm fe1)))). + intro Heq; apply AFth.(AF_1_neq_0). + rewrite <- (@AFinv_l AFth (NPEeval l (denum (Fnorm fe1))));trivial. + ring [Heq]. repeat rewrite (ARth.(ARmul_comm) (/ NPEeval l (denum (Fnorm fe1)))). + repeat rewrite <- (ARth.(ARmul_assoc)). + repeat rewrite <- (AFth.(AFdiv_def)). rewrite rdiv_r_r by trivial. + rewrite (AFth.(AFdiv_def)). ring_simplify. unfold SRopp. + rewrite (ARth.(ARmul_comm) (/ NPEeval l (denum (Fnorm fe2)))). + repeat rewrite <- (AFth.(AFdiv_def)). + repeat rewrite <- Fnorm_FEeval_PEeval ; trivial. + apply (PCond_app_inv_r _ _ _ H7). apply (PCond_app_inv_l _ _ _ H7). +Qed. + +Theorem Field_simplify_eq_in_correct : +forall n l lpe fe1 fe2, + Ninterp_PElist l lpe -> + forall lmp, Nmk_monpol_list lpe = lmp -> + forall nfe1, Fnorm fe1 = nfe1 -> + forall nfe2, Fnorm fe2 = nfe2 -> + forall den, split (denum nfe1) (denum nfe2) = den -> + forall np1, Nnorm n lmp (PEmul (num nfe1) (right den)) = np1 -> + forall np2, Nnorm n lmp (PEmul (num nfe2) (left den)) = np2 -> + FEeval l fe1 == FEeval l fe2 -> + PCond l (condition nfe1 ++ condition nfe2) -> + NPphi_dev l np1 == + NPphi_dev l np2. +Proof. + intros. subst nfe1 nfe2 lmp np1 np2. + repeat rewrite (Pphi_dev_ok Rsth Reqe ARth CRmorph get_sign_spec). + repeat (rewrite <- (norm_subst_ok Rsth Reqe ARth CRmorph pow_th);trivial). simpl. + assert (N1 := Pcond_Fnorm _ _ (PCond_app_inv_l _ _ _ H7)). + assert (N2 := Pcond_Fnorm _ _ (PCond_app_inv_r _ _ _ H7)). + apply (@rmul_reg_l (NPEeval l (rsplit_common den))). + intro Heq;apply N1. + rewrite (split_correct_l l (denum (Fnorm fe1)) (denum (Fnorm fe2))). + rewrite H3. rewrite NPEmul_correct. simpl. ring [Heq]. + repeat rewrite (ARth.(ARmul_comm) (NPEeval l (rsplit_common den))). + repeat rewrite <- ARth.(ARmul_assoc). + change (NPEeval l (rsplit_right den) * NPEeval l (rsplit_common den)) with + (NPEeval l (PEmul (rsplit_right den) (rsplit_common den))). + change (NPEeval l (rsplit_left den) * NPEeval l (rsplit_common den)) with + (NPEeval l (PEmul (rsplit_left den) (rsplit_common den))). + repeat rewrite <- NPEmul_correct;rewrite <- H3. rewrite <- split_correct_l. + rewrite <- split_correct_r. + apply (@rmul_reg_l (/NPEeval l (denum (Fnorm fe2)))). + intro Heq; apply AFth.(AF_1_neq_0). + rewrite <- (@AFinv_l AFth (NPEeval l (denum (Fnorm fe2))));trivial. + ring [Heq]. rewrite (ARth.(ARmul_comm) (/ NPEeval l (denum (Fnorm fe2)))). + repeat rewrite <- (ARth.(ARmul_assoc)). + rewrite <- (AFth.(AFdiv_def)). rewrite rdiv_r_r by trivial. + apply (@rmul_reg_l (/NPEeval l (denum (Fnorm fe1)))). + intro Heq; apply AFth.(AF_1_neq_0). + rewrite <- (@AFinv_l AFth (NPEeval l (denum (Fnorm fe1))));trivial. + ring [Heq]. repeat rewrite (ARth.(ARmul_comm) (/ NPEeval l (denum (Fnorm fe1)))). + repeat rewrite <- (ARth.(ARmul_assoc)). + repeat rewrite <- (AFth.(AFdiv_def)). rewrite rdiv_r_r by trivial. + rewrite (AFth.(AFdiv_def)). ring_simplify. unfold SRopp. + rewrite (ARth.(ARmul_comm) (/ NPEeval l (denum (Fnorm fe2)))). + repeat rewrite <- (AFth.(AFdiv_def)). + repeat rewrite <- Fnorm_FEeval_PEeval;trivial. + apply (PCond_app_inv_r _ _ _ H7). apply (PCond_app_inv_l _ _ _ H7). +Qed. + + +Section Fcons_impl. + +Variable Fcons : PExpr C -> list (PExpr C) -> list (PExpr C). + +Hypothesis PCond_fcons_inv : forall l a l1, + PCond l (Fcons a l1) -> ~ NPEeval l a == 0 /\ PCond l l1. + +Fixpoint Fapp (l m:list (PExpr C)) {struct l} : list (PExpr C) := + match l with + | nil => m + | cons a l1 => Fcons a (Fapp l1 m) + end. + +Lemma fcons_correct : forall l l1, + PCond l (Fapp l1 nil) -> PCond l l1. +induction l1; simpl in |- *; intros. + trivial. + elim PCond_fcons_inv with (1 := H); intros. + destruct l1; auto. +Qed. + +End Fcons_impl. + +Section Fcons_simpl. + +(* Some general simpifications of the condition: eliminate duplicates, + split multiplications *) + +Fixpoint Fcons (e:PExpr C) (l:list (PExpr C)) {struct l} : list (PExpr C) := + match l with + nil => cons e nil + | cons a l1 => if PExpr_eq e a then l else cons a (Fcons e l1) + end. + +Theorem PFcons_fcons_inv: + forall l a l1, PCond l (Fcons a l1) -> ~ NPEeval l a == 0 /\ PCond l l1. +intros l a l1; elim l1; simpl Fcons; auto. +simpl; auto. +intros a0 l0. +generalize (PExpr_eq_semi_correct l a a0); case (PExpr_eq a a0). +intros H H0 H1; split; auto. +rewrite H; auto. +generalize (PCond_cons_inv_l _ _ _ H1); simpl; auto. +intros H H0 H1; + assert (Hp: ~ NPEeval l a0 == 0 /\ (~ NPEeval l a == 0 /\ PCond l l0)). +split. +generalize (PCond_cons_inv_l _ _ _ H1); simpl; auto. +apply H0. +generalize (PCond_cons_inv_r _ _ _ H1); simpl; auto. +generalize Hp; case l0; simpl; intuition. +Qed. + +(* equality of normal forms rather than syntactic equality *) +Fixpoint Fcons0 (e:PExpr C) (l:list (PExpr C)) {struct l} : list (PExpr C) := + match l with + nil => cons e nil + | cons a l1 => + if Peq ceqb (Nnorm O nil e) (Nnorm O nil a) then l + else cons a (Fcons0 e l1) + end. + +Theorem PFcons0_fcons_inv: + forall l a l1, PCond l (Fcons0 a l1) -> ~ NPEeval l a == 0 /\ PCond l l1. +intros l a l1; elim l1; simpl Fcons0; auto. +simpl; auto. +intros a0 l0. +generalize (ring_correct Rsth Reqe ARth CRmorph pow_th cdiv_th O l nil a a0). simpl. + case (Peq ceqb (Nnorm O nil a) (Nnorm O nil a0)). +intros H H0 H1; split; auto. +rewrite H; auto. +generalize (PCond_cons_inv_l _ _ _ H1); simpl; auto. +intros H H0 H1; + assert (Hp: ~ NPEeval l a0 == 0 /\ (~ NPEeval l a == 0 /\ PCond l l0)). +split. +generalize (PCond_cons_inv_l _ _ _ H1); simpl; auto. +apply H0. +generalize (PCond_cons_inv_r _ _ _ H1); simpl; auto. +clear get_sign get_sign_spec. +generalize Hp; case l0; simpl; intuition. +Qed. + +(* split factorized denominators *) +Fixpoint Fcons00 (e:PExpr C) (l:list (PExpr C)) {struct e} : list (PExpr C) := + match e with + PEmul e1 e2 => Fcons00 e1 (Fcons00 e2 l) + | PEpow e1 _ => Fcons00 e1 l + | _ => Fcons0 e l + end. + +Theorem PFcons00_fcons_inv: + forall l a l1, PCond l (Fcons00 a l1) -> ~ NPEeval l a == 0 /\ PCond l l1. +intros l a; elim a; try (intros; apply PFcons0_fcons_inv; auto; fail). + intros p H p0 H0 l1 H1. + simpl in H1. + case (H _ H1); intros H2 H3. + case (H0 _ H3); intros H4 H5; split; auto. + simpl in |- *. + apply field_is_integral_domain; trivial. + simpl;intros. rewrite pow_th.(rpow_pow_N). + destruct (H _ H0);split;auto. + destruct n;simpl. apply AFth.(AF_1_neq_0). + apply pow_pos_not_0;trivial. +Qed. + +Definition Pcond_simpl_gen := + fcons_correct _ PFcons00_fcons_inv. + + +(* Specific case when the equality test of coefs is complete w.r.t. the + field equality: non-zero coefs can be eliminated, and opposite can + be simplified (if -1 <> 0) *) + +Hypothesis ceqb_complete : forall c1 c2, phi c1 == phi c2 -> ceqb c1 c2 = true. + +Lemma ceqb_rect_complete : forall c1 c2 (A:Type) (x y:A) (P:A->Type), + (phi c1 == phi c2 -> P x) -> + (~ phi c1 == phi c2 -> P y) -> + P (if ceqb c1 c2 then x else y). +Proof. +intros. +generalize (fun h => X (morph_eq CRmorph c1 c2 h)). +generalize (@ceqb_complete c1 c2). +case (c1 ?=! c2); auto; intros. +apply X0. +red in |- *; intro. +absurd (false = true); auto; discriminate. +Qed. + +Fixpoint Fcons1 (e:PExpr C) (l:list (PExpr C)) {struct e} : list (PExpr C) := + match e with + PEmul e1 e2 => Fcons1 e1 (Fcons1 e2 l) + | PEpow e _ => Fcons1 e l + | PEopp e => if ceqb (copp cI) cO then absurd_PCond else Fcons1 e l + | PEc c => if ceqb c cO then absurd_PCond else l + | _ => Fcons0 e l + end. + +Theorem PFcons1_fcons_inv: + forall l a l1, PCond l (Fcons1 a l1) -> ~ NPEeval l a == 0 /\ PCond l l1. +intros l a; elim a; try (intros; apply PFcons0_fcons_inv; auto; fail). + simpl in |- *; intros c l1. + apply ceqb_rect_complete; intros. + elim (@absurd_PCond_bottom l H0). + split; trivial. + rewrite <- (morph0 CRmorph) in |- *; trivial. + intros p H p0 H0 l1 H1. + simpl in H1. + case (H _ H1); intros H2 H3. + case (H0 _ H3); intros H4 H5; split; auto. + simpl in |- *. + apply field_is_integral_domain; trivial. + simpl in |- *; intros p H l1. + apply ceqb_rect_complete; intros. + elim (@absurd_PCond_bottom l H1). + destruct (H _ H1). + split; trivial. + apply ropp_neq_0; trivial. + rewrite (morph_opp CRmorph) in H0. + rewrite (morph1 CRmorph) in H0. + rewrite (morph0 CRmorph) in H0. + trivial. + intros;simpl. destruct (H _ H0);split;trivial. + rewrite pow_th.(rpow_pow_N). destruct n;simpl. + apply AFth.(AF_1_neq_0). apply pow_pos_not_0;trivial. +Qed. + +Definition Fcons2 e l := Fcons1 (PExpr_simp e) l. + +Theorem PFcons2_fcons_inv: + forall l a l1, PCond l (Fcons2 a l1) -> ~ NPEeval l a == 0 /\ PCond l l1. +unfold Fcons2 in |- *; intros l a l1 H; split; + case (PFcons1_fcons_inv l (PExpr_simp a) l1); auto. +intros H1 H2 H3; case H1. +transitivity (NPEeval l a); trivial. +apply PExpr_simp_correct. +Qed. + +Definition Pcond_simpl_complete := + fcons_correct _ PFcons2_fcons_inv. + +End Fcons_simpl. + +End AlmostField. + +Section FieldAndSemiField. + + Record field_theory : Prop := mk_field { + F_R : ring_theory rO rI radd rmul rsub ropp req; + F_1_neq_0 : ~ 1 == 0; + Fdiv_def : forall p q, p / q == p * / q; + Finv_l : forall p, ~ p == 0 -> / p * p == 1 + }. + + Definition F2AF f := + mk_afield + (Rth_ARth Rsth Reqe f.(F_R)) f.(F_1_neq_0) f.(Fdiv_def) f.(Finv_l). + + Record semi_field_theory : Prop := mk_sfield { + SF_SR : semi_ring_theory rO rI radd rmul req; + SF_1_neq_0 : ~ 1 == 0; + SFdiv_def : forall p q, p / q == p * / q; + SFinv_l : forall p, ~ p == 0 -> / p * p == 1 + }. + +End FieldAndSemiField. + +End MakeFieldPol. + + Definition SF2AF R (rO rI:R) radd rmul rdiv rinv req Rsth + (sf:semi_field_theory rO rI radd rmul rdiv rinv req) := + mk_afield _ _ + (SRth_ARth Rsth sf.(SF_SR)) + sf.(SF_1_neq_0) + sf.(SFdiv_def) + sf.(SFinv_l). + + +Section Complete. + Variable R : Type. + Variable (rO rI : R) (radd rmul rsub: R->R->R) (ropp : R -> R). + Variable (rdiv : R -> R -> R) (rinv : R -> R). + Variable req : R -> R -> Prop. + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Notation "x - y " := (rsub x y). Notation "- x" := (ropp x). + Notation "x / y " := (rdiv x y). Notation "/ x" := (rinv x). + Notation "x == y" := (req x y) (at level 70, no associativity). + Variable Rsth : Setoid_Theory R req. + Add Setoid R req Rsth as R_setoid3. + Variable Reqe : ring_eq_ext radd rmul ropp req. + Add Morphism radd : radd_ext3. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext3. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext3. exact (Ropp_ext Reqe). Qed. + +Section AlmostField. + + Variable AFth : almost_field_theory rO rI radd rmul rsub ropp rdiv rinv req. + Let ARth := AFth.(AF_AR). + Let rI_neq_rO := AFth.(AF_1_neq_0). + Let rdiv_def := AFth.(AFdiv_def). + Let rinv_l := AFth.(AFinv_l). + +Hypothesis S_inj : forall x y, 1+x==1+y -> x==y. + +Hypothesis gen_phiPOS_not_0 : forall p, ~ gen_phiPOS1 rI radd rmul p == 0. + +Lemma add_inj_r : forall p x y, + gen_phiPOS1 rI radd rmul p + x == gen_phiPOS1 rI radd rmul p + y -> x==y. +intros p x y. +elim p using Pind; simpl in |- *; intros. + apply S_inj; trivial. + apply H. + apply S_inj. + repeat rewrite (ARadd_assoc ARth) in |- *. + rewrite <- (ARgen_phiPOS_Psucc Rsth Reqe ARth) in |- *; trivial. +Qed. + +Lemma gen_phiPOS_inj : forall x y, + gen_phiPOS rI radd rmul x == gen_phiPOS rI radd rmul y -> + x = y. +intros x y. +repeat rewrite <- (same_gen Rsth Reqe ARth) in |- *. +ElimPcompare x y; intro. + intros. + apply Pcompare_Eq_eq; trivial. + intro. + elim gen_phiPOS_not_0 with (y - x)%positive. + apply add_inj_r with x. + symmetry in |- *. + rewrite (ARadd_0_r Rsth ARth) in |- *. + rewrite <- (ARgen_phiPOS_add Rsth Reqe ARth) in |- *. + rewrite Pplus_minus in |- *; trivial. + change Eq with (CompOpp Eq) in |- *. + rewrite <- Pcompare_antisym in |- *; trivial. + rewrite H in |- *; trivial. + intro. + elim gen_phiPOS_not_0 with (x - y)%positive. + apply add_inj_r with y. + rewrite (ARadd_0_r Rsth ARth) in |- *. + rewrite <- (ARgen_phiPOS_add Rsth Reqe ARth) in |- *. + rewrite Pplus_minus in |- *; trivial. +Qed. + + +Lemma gen_phiN_inj : forall x y, + gen_phiN rO rI radd rmul x == gen_phiN rO rI radd rmul y -> + x = y. +destruct x; destruct y; simpl in |- *; intros; trivial. + elim gen_phiPOS_not_0 with p. + symmetry in |- *. + rewrite (same_gen Rsth Reqe ARth) in |- *; trivial. + elim gen_phiPOS_not_0 with p. + rewrite (same_gen Rsth Reqe ARth) in |- *; trivial. + rewrite gen_phiPOS_inj with (1 := H) in |- *; trivial. +Qed. + +Lemma gen_phiN_complete : forall x y, + gen_phiN rO rI radd rmul x == gen_phiN rO rI radd rmul y -> + Neq_bool x y = true. +intros. + replace y with x. + unfold Neq_bool in |- *. + rewrite Ncompare_refl in |- *; trivial. + apply gen_phiN_inj; trivial. +Qed. + +End AlmostField. + +Section Field. + + Variable Fth : field_theory rO rI radd rmul rsub ropp rdiv rinv req. + Let Rth := Fth.(F_R). + Let rI_neq_rO := Fth.(F_1_neq_0). + Let rdiv_def := Fth.(Fdiv_def). + Let rinv_l := Fth.(Finv_l). + Let AFth := F2AF Rsth Reqe Fth. + Let ARth := Rth_ARth Rsth Reqe Rth. + +Lemma ring_S_inj : forall x y, 1+x==1+y -> x==y. +intros. +transitivity (x + (1 + - (1))). + rewrite (Ropp_def Rth) in |- *. + symmetry in |- *. + apply (ARadd_0_r Rsth ARth). + transitivity (y + (1 + - (1))). + repeat rewrite <- (ARplus_assoc ARth) in |- *. + repeat rewrite (ARadd_assoc ARth) in |- *. + apply (Radd_ext Reqe). + repeat rewrite <- (ARadd_comm ARth 1) in |- *. + trivial. + reflexivity. + rewrite (Ropp_def Rth) in |- *. + apply (ARadd_0_r Rsth ARth). +Qed. + + + Hypothesis gen_phiPOS_not_0 : forall p, ~ gen_phiPOS1 rI radd rmul p == 0. + +Let gen_phiPOS_inject := + gen_phiPOS_inj AFth ring_S_inj gen_phiPOS_not_0. + +Lemma gen_phiPOS_discr_sgn : forall x y, + ~ gen_phiPOS rI radd rmul x == - gen_phiPOS rI radd rmul y. +red in |- *; intros. +apply gen_phiPOS_not_0 with (y + x)%positive. +rewrite (ARgen_phiPOS_add Rsth Reqe ARth) in |- *. +transitivity (gen_phiPOS1 1 radd rmul y + - gen_phiPOS1 1 radd rmul y). + apply (Radd_ext Reqe); trivial. + reflexivity. + rewrite (same_gen Rsth Reqe ARth) in |- *. + rewrite (same_gen Rsth Reqe ARth) in |- *. + trivial. + apply (Ropp_def Rth). +Qed. + +Lemma gen_phiZ_inj : forall x y, + gen_phiZ rO rI radd rmul ropp x == gen_phiZ rO rI radd rmul ropp y -> + x = y. +destruct x; destruct y; simpl in |- *; intros. + trivial. + elim gen_phiPOS_not_0 with p. + rewrite (same_gen Rsth Reqe ARth) in |- *. + symmetry in |- *; trivial. + elim gen_phiPOS_not_0 with p. + rewrite (same_gen Rsth Reqe ARth) in |- *. + rewrite <- (Ropp_opp Rsth Reqe Rth (gen_phiPOS 1 radd rmul p)) in |- *. + rewrite <- H in |- *. + apply (ARopp_zero Rsth Reqe ARth). + elim gen_phiPOS_not_0 with p. + rewrite (same_gen Rsth Reqe ARth) in |- *. + trivial. + rewrite gen_phiPOS_inject with (1 := H) in |- *; trivial. + elim gen_phiPOS_discr_sgn with (1 := H). + elim gen_phiPOS_not_0 with p. + rewrite (same_gen Rsth Reqe ARth) in |- *. + rewrite <- (Ropp_opp Rsth Reqe Rth (gen_phiPOS 1 radd rmul p)) in |- *. + rewrite H in |- *. + apply (ARopp_zero Rsth Reqe ARth). + elim gen_phiPOS_discr_sgn with p0 p. + symmetry in |- *; trivial. + replace p0 with p; trivial. + apply gen_phiPOS_inject. + rewrite <- (Ropp_opp Rsth Reqe Rth (gen_phiPOS 1 radd rmul p)) in |- *. + rewrite <- (Ropp_opp Rsth Reqe Rth (gen_phiPOS 1 radd rmul p0)) in |- *. + rewrite H in |- *; trivial. + reflexivity. +Qed. + +Lemma gen_phiZ_complete : forall x y, + gen_phiZ rO rI radd rmul ropp x == gen_phiZ rO rI radd rmul ropp y -> + Zeq_bool x y = true. +intros. + replace y with x. + unfold Zeq_bool in |- *. + rewrite Zcompare_refl in |- *; trivial. + apply gen_phiZ_inj; trivial. +Qed. + +End Field. + +End Complete. diff --git a/plugins/setoid_ring/InitialRing.v b/plugins/setoid_ring/InitialRing.v new file mode 100644 index 00000000..b5384f80 --- /dev/null +++ b/plugins/setoid_ring/InitialRing.v @@ -0,0 +1,908 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* R->R) (ropp : R -> R). + Variable req : R -> R -> Prop. + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Notation "x - y " := (rsub x y). Notation "- x" := (ropp x). + Notation "x == y" := (req x y). + Variable Rsth : Setoid_Theory R req. + Add Setoid R req Rsth as R_setoid3. + Ltac rrefl := gen_reflexivity Rsth. + Variable Reqe : ring_eq_ext radd rmul ropp req. + Add Morphism radd : radd_ext3. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext3. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext3. exact (Ropp_ext Reqe). Qed. + + Fixpoint gen_phiPOS1 (p:positive) : R := + match p with + | xH => 1 + | xO p => (1 + 1) * (gen_phiPOS1 p) + | xI p => 1 + ((1 + 1) * (gen_phiPOS1 p)) + end. + + Fixpoint gen_phiPOS (p:positive) : R := + match p with + | xH => 1 + | xO xH => (1 + 1) + | xO p => (1 + 1) * (gen_phiPOS p) + | xI xH => 1 + (1 +1) + | xI p => 1 + ((1 + 1) * (gen_phiPOS p)) + end. + + Definition gen_phiZ1 z := + match z with + | Zpos p => gen_phiPOS1 p + | Z0 => 0 + | Zneg p => -(gen_phiPOS1 p) + end. + + Definition gen_phiZ z := + match z with + | Zpos p => gen_phiPOS p + | Z0 => 0 + | Zneg p => -(gen_phiPOS p) + end. + Notation "[ x ]" := (gen_phiZ x). + + Definition get_signZ z := + match z with + | Zneg p => Some (Zpos p) + | _ => None + end. + + Lemma get_signZ_th : sign_theory Zopp Zeq_bool get_signZ. + Proof. + constructor. + destruct c;intros;try discriminate. + injection H;clear H;intros H1;subst c'. + simpl. unfold Zeq_bool. rewrite Zcompare_refl. trivial. + Qed. + + + Section ALMOST_RING. + Variable ARth : almost_ring_theory 0 1 radd rmul rsub ropp req. + Add Morphism rsub : rsub_ext3. exact (ARsub_ext Rsth Reqe ARth). Qed. + Ltac norm := gen_srewrite Rsth Reqe ARth. + Ltac add_push := gen_add_push radd Rsth Reqe ARth. + + Lemma same_gen : forall x, gen_phiPOS1 x == gen_phiPOS x. + Proof. + induction x;simpl. + rewrite IHx;destruct x;simpl;norm. + rewrite IHx;destruct x;simpl;norm. + rrefl. + Qed. + + Lemma ARgen_phiPOS_Psucc : forall x, + gen_phiPOS1 (Psucc x) == 1 + (gen_phiPOS1 x). + Proof. + induction x;simpl;norm. + rewrite IHx;norm. + add_push 1;rrefl. + Qed. + + Lemma ARgen_phiPOS_add : forall x y, + gen_phiPOS1 (x + y) == (gen_phiPOS1 x) + (gen_phiPOS1 y). + Proof. + induction x;destruct y;simpl;norm. + rewrite Pplus_carry_spec. + rewrite ARgen_phiPOS_Psucc. + rewrite IHx;norm. + add_push (gen_phiPOS1 y);add_push 1;rrefl. + rewrite IHx;norm;add_push (gen_phiPOS1 y);rrefl. + rewrite ARgen_phiPOS_Psucc;norm;add_push 1;rrefl. + rewrite IHx;norm;add_push(gen_phiPOS1 y); add_push 1;rrefl. + rewrite IHx;norm;add_push(gen_phiPOS1 y);rrefl. + add_push 1;rrefl. + rewrite ARgen_phiPOS_Psucc;norm;add_push 1;rrefl. + Qed. + + Lemma ARgen_phiPOS_mult : + forall x y, gen_phiPOS1 (x * y) == gen_phiPOS1 x * gen_phiPOS1 y. + Proof. + induction x;intros;simpl;norm. + rewrite ARgen_phiPOS_add;simpl;rewrite IHx;norm. + rewrite IHx;rrefl. + Qed. + + End ALMOST_RING. + + Variable Rth : ring_theory 0 1 radd rmul rsub ropp req. + Let ARth := Rth_ARth Rsth Reqe Rth. + Add Morphism rsub : rsub_ext4. exact (ARsub_ext Rsth Reqe ARth). Qed. + Ltac norm := gen_srewrite Rsth Reqe ARth. + Ltac add_push := gen_add_push radd Rsth Reqe ARth. + +(*morphisms are extensionaly equal*) + Lemma same_genZ : forall x, [x] == gen_phiZ1 x. + Proof. + destruct x;simpl; try rewrite (same_gen ARth);rrefl. + Qed. + + Lemma gen_Zeqb_ok : forall x y, + Zeq_bool x y = true -> [x] == [y]. + Proof. + intros x y H. + assert (H1 := Zeq_bool_eq x y H);unfold IDphi in H1. + rewrite H1;rrefl. + Qed. + + Lemma gen_phiZ1_add_pos_neg : forall x y, + gen_phiZ1 + match (x ?= y)%positive Eq with + | Eq => Z0 + | Lt => Zneg (y - x) + | Gt => Zpos (x - y) + end + == gen_phiPOS1 x + -gen_phiPOS1 y. + Proof. + intros x y. + assert (H:= (Pcompare_Eq_eq x y)); assert (H0 := Pminus_mask_Gt x y). + generalize (Pminus_mask_Gt y x). + replace Eq with (CompOpp Eq);[intro H1;simpl|trivial]. + rewrite <- Pcompare_antisym in H1. + destruct ((x ?= y)%positive Eq). + rewrite H;trivial. rewrite (Ropp_def Rth);rrefl. + destruct H1 as [h [Heq1 [Heq2 Hor]]];trivial. + unfold Pminus; rewrite Heq1;rewrite <- Heq2. + rewrite (ARgen_phiPOS_add ARth);simpl;norm. + rewrite (Ropp_def Rth);norm. + destruct H0 as [h [Heq1 [Heq2 Hor]]];trivial. + unfold Pminus; rewrite Heq1;rewrite <- Heq2. + rewrite (ARgen_phiPOS_add ARth);simpl;norm. + add_push (gen_phiPOS1 h);rewrite (Ropp_def Rth); norm. + Qed. + + Lemma match_compOpp : forall x (B:Type) (be bl bg:B), + match CompOpp x with Eq => be | Lt => bl | Gt => bg end + = match x with Eq => be | Lt => bg | Gt => bl end. + Proof. destruct x;simpl;intros;trivial. Qed. + + Lemma gen_phiZ_add : forall x y, [x + y] == [x] + [y]. + Proof. + intros x y; repeat rewrite same_genZ; generalize x y;clear x y. + induction x;destruct y;simpl;norm. + apply (ARgen_phiPOS_add ARth). + apply gen_phiZ1_add_pos_neg. + replace Eq with (CompOpp Eq);trivial. + rewrite <- Pcompare_antisym;simpl. + rewrite match_compOpp. + rewrite (Radd_comm Rth). + apply gen_phiZ1_add_pos_neg. + rewrite (ARgen_phiPOS_add ARth); norm. + Qed. + + Lemma gen_phiZ_mul : forall x y, [x * y] == [x] * [y]. + Proof. + intros x y;repeat rewrite same_genZ. + destruct x;destruct y;simpl;norm; + rewrite (ARgen_phiPOS_mult ARth);try (norm;fail). + rewrite (Ropp_opp Rsth Reqe Rth);rrefl. + Qed. + + Lemma gen_phiZ_ext : forall x y : Z, x = y -> [x] == [y]. + Proof. intros;subst;rrefl. Qed. + +(*proof that [.] satisfies morphism specifications*) + Lemma gen_phiZ_morph : + ring_morph 0 1 radd rmul rsub ropp req Z0 (Zpos xH) + Zplus Zmult Zminus Zopp Zeq_bool gen_phiZ. + Proof. + assert ( SRmorph : semi_morph 0 1 radd rmul req Z0 (Zpos xH) + Zplus Zmult Zeq_bool gen_phiZ). + apply mkRmorph;simpl;try rrefl. + apply gen_phiZ_add. apply gen_phiZ_mul. apply gen_Zeqb_ok. + apply (Smorph_morph Rsth Reqe Rth Zth SRmorph gen_phiZ_ext). + Qed. + +End ZMORPHISM. + +(** N is a semi-ring and a setoid*) +Lemma Nsth : Setoid_Theory N (@eq N). +Proof (Eqsth N). + +Lemma Nseqe : sring_eq_ext Nplus Nmult (@eq N). +Proof (Eq_s_ext Nplus Nmult). + +Lemma Nth : semi_ring_theory N0 (Npos xH) Nplus Nmult (@eq N). +Proof. + constructor. exact Nplus_0_l. exact Nplus_comm. exact Nplus_assoc. + exact Nmult_1_l. exact Nmult_0_l. exact Nmult_comm. exact Nmult_assoc. + exact Nmult_plus_distr_r. +Qed. + +Definition Nsub := SRsub Nplus. +Definition Nopp := (@SRopp N). + +Lemma Neqe : ring_eq_ext Nplus Nmult Nopp (@eq N). +Proof (SReqe_Reqe Nseqe). + +Lemma Nath : + almost_ring_theory N0 (Npos xH) Nplus Nmult Nsub Nopp (@eq N). +Proof (SRth_ARth Nsth Nth). + +Definition Neq_bool (x y:N) := + match Ncompare x y with + | Eq => true + | _ => false + end. + +Lemma Neq_bool_ok : forall x y, Neq_bool x y = true -> x = y. + Proof. + intros x y;unfold Neq_bool. + assert (H:=Ncompare_Eq_eq x y); + destruct (Ncompare x y);intros;try discriminate. + rewrite H;trivial. + Qed. + +Lemma Neq_bool_complete : forall x y, Neq_bool x y = true -> x = y. + Proof. + intros x y;unfold Neq_bool. + assert (H:=Ncompare_Eq_eq x y); + destruct (Ncompare x y);intros;try discriminate. + rewrite H;trivial. + Qed. + +(**Same as above : definition of two,extensionaly equal, generic morphisms *) +(**from N to any semi-ring*) +Section NMORPHISM. + Variable R : Type. + Variable (rO rI : R) (radd rmul: R->R->R). + Variable req : R -> R -> Prop. + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Variable Rsth : Setoid_Theory R req. + Add Setoid R req Rsth as R_setoid4. + Ltac rrefl := gen_reflexivity Rsth. + Variable SReqe : sring_eq_ext radd rmul req. + Variable SRth : semi_ring_theory 0 1 radd rmul req. + Let ARth := SRth_ARth Rsth SRth. + Let Reqe := SReqe_Reqe SReqe. + Let ropp := (@SRopp R). + Let rsub := (@SRsub R radd). + Notation "x - y " := (rsub x y). Notation "- x" := (ropp x). + Notation "x == y" := (req x y). + Add Morphism radd : radd_ext4. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext4. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext4. exact (Ropp_ext Reqe). Qed. + Add Morphism rsub : rsub_ext5. exact (ARsub_ext Rsth Reqe ARth). Qed. + Ltac norm := gen_srewrite Rsth Reqe ARth. + + Definition gen_phiN1 x := + match x with + | N0 => 0 + | Npos x => gen_phiPOS1 1 radd rmul x + end. + + Definition gen_phiN x := + match x with + | N0 => 0 + | Npos x => gen_phiPOS 1 radd rmul x + end. + Notation "[ x ]" := (gen_phiN x). + + Lemma same_genN : forall x, [x] == gen_phiN1 x. + Proof. + destruct x;simpl. rrefl. + rewrite (same_gen Rsth Reqe ARth);rrefl. + Qed. + + Lemma gen_phiN_add : forall x y, [x + y] == [x] + [y]. + Proof. + intros x y;repeat rewrite same_genN. + destruct x;destruct y;simpl;norm. + apply (ARgen_phiPOS_add Rsth Reqe ARth). + Qed. + + Lemma gen_phiN_mult : forall x y, [x * y] == [x] * [y]. + Proof. + intros x y;repeat rewrite same_genN. + destruct x;destruct y;simpl;norm. + apply (ARgen_phiPOS_mult Rsth Reqe ARth). + Qed. + + Lemma gen_phiN_sub : forall x y, [Nsub x y] == [x] - [y]. + Proof. exact gen_phiN_add. Qed. + +(*gen_phiN satisfies morphism specifications*) + Lemma gen_phiN_morph : ring_morph 0 1 radd rmul rsub ropp req + N0 (Npos xH) Nplus Nmult Nsub Nopp Neq_bool gen_phiN. + Proof. + constructor;intros;simpl; try rrefl. + apply gen_phiN_add. apply gen_phiN_sub. apply gen_phiN_mult. + rewrite (Neq_bool_ok x y);trivial. rrefl. + Qed. + +End NMORPHISM. + +(* Words on N : initial structure for almost-rings. *) +Definition Nword := list N. +Definition NwO : Nword := nil. +Definition NwI : Nword := 1%N :: nil. + +Definition Nwcons n (w : Nword) : Nword := + match w, n with + | nil, 0%N => nil + | _, _ => n :: w + end. + +Fixpoint Nwadd (w1 w2 : Nword) {struct w1} : Nword := + match w1, w2 with + | n1::w1', n2:: w2' => (n1+n2)%N :: Nwadd w1' w2' + | nil, _ => w2 + | _, nil => w1 + end. + +Definition Nwopp (w:Nword) : Nword := Nwcons 0%N w. + +Definition Nwsub w1 w2 := Nwadd w1 (Nwopp w2). + +Fixpoint Nwscal (n : N) (w : Nword) {struct w} : Nword := + match w with + | m :: w' => (n*m)%N :: Nwscal n w' + | nil => nil + end. + +Fixpoint Nwmul (w1 w2 : Nword) {struct w1} : Nword := + match w1 with + | 0%N::w1' => Nwopp (Nwmul w1' w2) + | n1::w1' => Nwsub (Nwscal n1 w2) (Nwmul w1' w2) + | nil => nil + end. +Fixpoint Nw_is0 (w : Nword) : bool := + match w with + | nil => true + | 0%N :: w' => Nw_is0 w' + | _ => false + end. + +Fixpoint Nweq_bool (w1 w2 : Nword) {struct w1} : bool := + match w1, w2 with + | n1::w1', n2::w2' => + if Neq_bool n1 n2 then Nweq_bool w1' w2' else false + | nil, _ => Nw_is0 w2 + | _, nil => Nw_is0 w1 + end. + +Section NWORDMORPHISM. + Variable R : Type. + Variable (rO rI : R) (radd rmul rsub: R->R->R) (ropp : R -> R). + Variable req : R -> R -> Prop. + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Notation "x - y " := (rsub x y). Notation "- x" := (ropp x). + Notation "x == y" := (req x y). + Variable Rsth : Setoid_Theory R req. + Add Setoid R req Rsth as R_setoid5. + Ltac rrefl := gen_reflexivity Rsth. + Variable Reqe : ring_eq_ext radd rmul ropp req. + Add Morphism radd : radd_ext5. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext5. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext5. exact (Ropp_ext Reqe). Qed. + + Variable ARth : almost_ring_theory 0 1 radd rmul rsub ropp req. + Add Morphism rsub : rsub_ext7. exact (ARsub_ext Rsth Reqe ARth). Qed. + Ltac norm := gen_srewrite Rsth Reqe ARth. + Ltac add_push := gen_add_push radd Rsth Reqe ARth. + + Fixpoint gen_phiNword (w : Nword) : R := + match w with + | nil => 0 + | n :: nil => gen_phiN rO rI radd rmul n + | N0 :: w' => - gen_phiNword w' + | n::w' => gen_phiN rO rI radd rmul n - gen_phiNword w' + end. + + Lemma gen_phiNword0_ok : forall w, Nw_is0 w = true -> gen_phiNword w == 0. +Proof. +induction w; simpl in |- *; intros; auto. + reflexivity. + + destruct a. + destruct w. + reflexivity. + + rewrite IHw in |- *; trivial. + apply (ARopp_zero Rsth Reqe ARth). + + discriminate. +Qed. + + Lemma gen_phiNword_cons : forall w n, + gen_phiNword (n::w) == gen_phiN rO rI radd rmul n - gen_phiNword w. +induction w. + destruct n; simpl in |- *; norm. + + intros. + destruct n; norm. +Qed. + + Lemma gen_phiNword_Nwcons : forall w n, + gen_phiNword (Nwcons n w) == gen_phiN rO rI radd rmul n - gen_phiNword w. +destruct w; intros. + destruct n; norm. + + unfold Nwcons in |- *. + rewrite gen_phiNword_cons in |- *. + reflexivity. +Qed. + + Lemma gen_phiNword_ok : forall w1 w2, + Nweq_bool w1 w2 = true -> gen_phiNword w1 == gen_phiNword w2. +induction w1; intros. + simpl in |- *. + rewrite (gen_phiNword0_ok _ H) in |- *. + reflexivity. + + rewrite gen_phiNword_cons in |- *. + destruct w2. + simpl in H. + destruct a; try discriminate. + rewrite (gen_phiNword0_ok _ H) in |- *. + norm. + + simpl in H. + rewrite gen_phiNword_cons in |- *. + case_eq (Neq_bool a n); intros. + rewrite H0 in H. + rewrite <- (Neq_bool_ok _ _ H0) in |- *. + rewrite (IHw1 _ H) in |- *. + reflexivity. + + rewrite H0 in H; discriminate H. +Qed. + + +Lemma Nwadd_ok : forall x y, + gen_phiNword (Nwadd x y) == gen_phiNword x + gen_phiNword y. +induction x; intros. + simpl in |- *. + norm. + + destruct y. + simpl Nwadd; norm. + + simpl Nwadd in |- *. + repeat rewrite gen_phiNword_cons in |- *. + rewrite (fun sreq => gen_phiN_add Rsth sreq (ARth_SRth ARth)) in |- * by + (destruct Reqe; constructor; trivial). + + rewrite IHx in |- *. + norm. + add_push (- gen_phiNword x); reflexivity. +Qed. + +Lemma Nwopp_ok : forall x, gen_phiNword (Nwopp x) == - gen_phiNword x. +simpl in |- *. +unfold Nwopp in |- *; simpl in |- *. +intros. +rewrite gen_phiNword_Nwcons in |- *; norm. +Qed. + +Lemma Nwscal_ok : forall n x, + gen_phiNword (Nwscal n x) == gen_phiN rO rI radd rmul n * gen_phiNword x. +induction x; intros. + norm. + + simpl Nwscal in |- *. + repeat rewrite gen_phiNword_cons in |- *. + rewrite (fun sreq => gen_phiN_mult Rsth sreq (ARth_SRth ARth)) in |- * + by (destruct Reqe; constructor; trivial). + + rewrite IHx in |- *. + norm. +Qed. + +Lemma Nwmul_ok : forall x y, + gen_phiNword (Nwmul x y) == gen_phiNword x * gen_phiNword y. +induction x; intros. + norm. + + destruct a. + simpl Nwmul in |- *. + rewrite Nwopp_ok in |- *. + rewrite IHx in |- *. + rewrite gen_phiNword_cons in |- *. + norm. + + simpl Nwmul in |- *. + unfold Nwsub in |- *. + rewrite Nwadd_ok in |- *. + rewrite Nwscal_ok in |- *. + rewrite Nwopp_ok in |- *. + rewrite IHx in |- *. + rewrite gen_phiNword_cons in |- *. + norm. +Qed. + +(* Proof that [.] satisfies morphism specifications *) + Lemma gen_phiNword_morph : + ring_morph 0 1 radd rmul rsub ropp req + NwO NwI Nwadd Nwmul Nwsub Nwopp Nweq_bool gen_phiNword. +constructor. + reflexivity. + + reflexivity. + + exact Nwadd_ok. + + intros. + unfold Nwsub in |- *. + rewrite Nwadd_ok in |- *. + rewrite Nwopp_ok in |- *. + norm. + + exact Nwmul_ok. + + exact Nwopp_ok. + + exact gen_phiNword_ok. +Qed. + +End NWORDMORPHISM. + +Section GEN_DIV. + + Variables (R : Type) (rO : R) (rI : R) (radd : R -> R -> R) + (rmul : R -> R -> R) (rsub : R -> R -> R) (ropp : R -> R) + (req : R -> R -> Prop) (C : Type) (cO : C) (cI : C) + (cadd : C -> C -> C) (cmul : C -> C -> C) (csub : C -> C -> C) + (copp : C -> C) (ceqb : C -> C -> bool) (phi : C -> R). + Variable Rsth : Setoid_Theory R req. + Variable Reqe : ring_eq_ext radd rmul ropp req. + Variable ARth : almost_ring_theory rO rI radd rmul rsub ropp req. + Variable morph : ring_morph rO rI radd rmul rsub ropp req cO cI cadd cmul csub copp ceqb phi. + + (* Useful tactics *) + Add Setoid R req Rsth as R_set1. + Ltac rrefl := gen_reflexivity Rsth. + Add Morphism radd : radd_ext. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext. exact (Ropp_ext Reqe). Qed. + Add Morphism rsub : rsub_ext. exact (ARsub_ext Rsth Reqe ARth). Qed. + Ltac rsimpl := gen_srewrite Rsth Reqe ARth. + + Definition triv_div x y := + if ceqb x y then (cI, cO) + else (cO, x). + + Ltac Esimpl :=repeat (progress ( + match goal with + | |- context [phi cO] => rewrite (morph0 morph) + | |- context [phi cI] => rewrite (morph1 morph) + | |- context [phi (cadd ?x ?y)] => rewrite ((morph_add morph) x y) + | |- context [phi (cmul ?x ?y)] => rewrite ((morph_mul morph) x y) + | |- context [phi (csub ?x ?y)] => rewrite ((morph_sub morph) x y) + | |- context [phi (copp ?x)] => rewrite ((morph_opp morph) x) + end)). + + Lemma triv_div_th : Ring_theory.div_theory req cadd cmul phi triv_div. + Proof. + constructor. + intros a b;unfold triv_div. + assert (X:= morph.(morph_eq) a b);destruct (ceqb a b). + Esimpl. + rewrite X; trivial. + rsimpl. + Esimpl; rsimpl. +Qed. + + Variable zphi : Z -> R. + + Lemma Ztriv_div_th : div_theory req Zplus Zmult zphi ZOdiv_eucl. + Proof. + constructor. + intros; generalize (ZOdiv_eucl_correct a b); case ZOdiv_eucl; intros; subst. + rewrite Zmult_comm; rsimpl. + Qed. + + Variable nphi : N -> R. + + Lemma Ntriv_div_th : div_theory req Nplus Nmult nphi Ndiv_eucl. + constructor. + intros; generalize (Ndiv_eucl_correct a b); case Ndiv_eucl; intros; subst. + rewrite Nmult_comm; rsimpl. + Qed. + +End GEN_DIV. + + (* syntaxification of constants in an abstract ring: + the inverse of gen_phiPOS *) + Ltac inv_gen_phi_pos rI add mul t := + let rec inv_cst t := + match t with + rI => constr:1%positive + | (add rI rI) => constr:2%positive + | (add rI (add rI rI)) => constr:3%positive + | (mul (add rI rI) ?p) => (* 2p *) + match inv_cst p with + NotConstant => constr:NotConstant + | 1%positive => constr:NotConstant (* 2*1 is not convertible to 2 *) + | ?p => constr:(xO p) + end + | (add rI (mul (add rI rI) ?p)) => (* 1+2p *) + match inv_cst p with + NotConstant => constr:NotConstant + | 1%positive => constr:NotConstant + | ?p => constr:(xI p) + end + | _ => constr:NotConstant + end in + inv_cst t. + +(* The (partial) inverse of gen_phiNword *) + Ltac inv_gen_phiNword rO rI add mul opp t := + match t with + rO => constr:NwO + | _ => + match inv_gen_phi_pos rI add mul t with + NotConstant => constr:NotConstant + | ?p => constr:(Npos p::nil) + end + end. + + +(* The inverse of gen_phiN *) + Ltac inv_gen_phiN rO rI add mul t := + match t with + rO => constr:0%N + | _ => + match inv_gen_phi_pos rI add mul t with + NotConstant => constr:NotConstant + | ?p => constr:(Npos p) + end + end. + +(* The inverse of gen_phiZ *) + Ltac inv_gen_phiZ rO rI add mul opp t := + match t with + rO => constr:0%Z + | (opp ?p) => + match inv_gen_phi_pos rI add mul p with + NotConstant => constr:NotConstant + | ?p => constr:(Zneg p) + end + | _ => + match inv_gen_phi_pos rI add mul t with + NotConstant => constr:NotConstant + | ?p => constr:(Zpos p) + end + end. + +(* A simple tactic recognizing only 0 and 1. The inv_gen_phiX above + are only optimisations that directly returns the reifid constant + instead of resorting to the constant propagation of the simplification + algorithm. *) +Ltac inv_gen_phi rO rI cO cI t := + match t with + | rO => cO + | rI => cI + end. + +(* A simple tactic recognizing no constant *) + Ltac inv_morph_nothing t := constr:NotConstant. + +Ltac coerce_to_almost_ring set ext rspec := + match type of rspec with + | ring_theory _ _ _ _ _ _ _ => constr:(Rth_ARth set ext rspec) + | semi_ring_theory _ _ _ _ _ => constr:(SRth_ARth set rspec) + | almost_ring_theory _ _ _ _ _ _ _ => rspec + | _ => fail 1 "not a valid ring theory" + end. + +Ltac coerce_to_ring_ext ext := + match type of ext with + | ring_eq_ext _ _ _ _ => ext + | sring_eq_ext _ _ _ => constr:(SReqe_Reqe ext) + | _ => fail 1 "not a valid ring_eq_ext theory" + end. + +Ltac abstract_ring_morphism set ext rspec := + match type of rspec with + | ring_theory _ _ _ _ _ _ _ => constr:(gen_phiZ_morph set ext rspec) + | semi_ring_theory _ _ _ _ _ => constr:(gen_phiN_morph set ext rspec) + | almost_ring_theory _ _ _ _ _ _ _ => + constr:(gen_phiNword_morph set ext rspec) + | _ => fail 1 "bad ring structure" + end. + +Record hypo : Type := mkhypo { + hypo_type : Type; + hypo_proof : hypo_type + }. + +Ltac gen_ring_pow set arth pspec := + match pspec with + | None => + match type of arth with + | @almost_ring_theory ?R ?rO ?rI ?radd ?rmul ?rsub ?ropp ?req => + constr:(mkhypo (@pow_N_th R rI rmul req set)) + | _ => fail 1 "gen_ring_pow" + end + | Some ?t => constr:(t) + end. + +Ltac gen_ring_sign morph sspec := + match sspec with + | None => + match type of morph with + | @ring_morph ?R ?r0 ?rI ?radd ?rmul ?rsub ?ropp ?req + Z ?c0 ?c1 ?cadd ?cmul ?csub ?copp ?ceqb ?phi => + constr:(@mkhypo (sign_theory copp ceqb get_signZ) get_signZ_th) + | @ring_morph ?R ?r0 ?rI ?radd ?rmul ?rsub ?ropp ?req + ?C ?c0 ?c1 ?cadd ?cmul ?csub ?copp ?ceqb ?phi => + constr:(mkhypo (@get_sign_None_th C copp ceqb)) + | _ => fail 2 "ring anomaly : default_sign_spec" + end + | Some ?t => constr:(t) + end. + +Ltac default_div_spec set reqe arth morph := + match type of morph with + | @ring_morph ?R ?r0 ?rI ?radd ?rmul ?rsub ?ropp ?req + Z ?c0 ?c1 Zplus Zmult ?csub ?copp ?ceq_b ?phi => + constr:(mkhypo (Ztriv_div_th set phi)) + | @ring_morph ?R ?r0 ?rI ?radd ?rmul ?rsub ?ropp ?req + N ?c0 ?c1 Nplus Nmult ?csub ?copp ?ceq_b ?phi => + constr:(mkhypo (Ntriv_div_th set phi)) + | @ring_morph ?R ?r0 ?rI ?radd ?rmul ?rsub ?ropp ?req + ?C ?c0 ?c1 ?cadd ?cmul ?csub ?copp ?ceq_b ?phi => + constr:(mkhypo (triv_div_th set reqe arth morph)) + | _ => fail 1 "ring anomaly : default_sign_spec" + end. + +Ltac gen_ring_div set reqe arth morph dspec := + match dspec with + | None => default_div_spec set reqe arth morph + | Some ?t => constr:(t) + end. + +Ltac ring_elements set ext rspec pspec sspec dspec rk := + let arth := coerce_to_almost_ring set ext rspec in + let ext_r := coerce_to_ring_ext ext in + let morph := + match rk with + | Abstract => abstract_ring_morphism set ext rspec + | @Computational ?reqb_ok => + match type of arth with + | almost_ring_theory ?rO ?rI ?add ?mul ?sub ?opp _ => + constr:(IDmorph rO rI add mul sub opp set _ reqb_ok) + | _ => fail 2 "ring anomaly" + end + | @Morphism ?m => + match type of m with + | ring_morph _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ => m + | @semi_morph _ _ _ _ _ _ _ _ _ _ _ _ _ => + constr:(SRmorph_Rmorph set m) + | _ => fail 2 "ring anomaly" + end + | _ => fail 1 "ill-formed ring kind" + end in + let p_spec := gen_ring_pow set arth pspec in + let s_spec := gen_ring_sign morph sspec in + let d_spec := gen_ring_div set ext_r arth morph dspec in + fun f => f arth ext_r morph p_spec s_spec d_spec. + +(* Given a ring structure and the kind of morphism, + returns 2 lemmas (one for ring, and one for ring_simplify). *) + + Ltac ring_lemmas set ext rspec pspec sspec dspec rk := + let gen_lemma2 := + match pspec with + | None => constr:(ring_rw_correct) + | Some _ => constr:(ring_rw_pow_correct) + end in + ring_elements set ext rspec pspec sspec dspec rk + ltac:(fun arth ext_r morph p_spec s_spec d_spec => + match type of morph with + | @ring_morph ?R ?r0 ?rI ?radd ?rmul ?rsub ?ropp ?req + ?C ?c0 ?c1 ?cadd ?cmul ?csub ?copp ?ceq_b ?phi => + let gen_lemma2_0 := + constr:(gen_lemma2 R r0 rI radd rmul rsub ropp req set ext_r arth + C c0 c1 cadd cmul csub copp ceq_b phi morph) in + match p_spec with + | @mkhypo (power_theory _ _ _ ?Cp_phi ?rpow) ?pp_spec => + let gen_lemma2_1 := constr:(gen_lemma2_0 _ Cp_phi rpow pp_spec) in + match d_spec with + | @mkhypo (div_theory _ _ _ _ ?cdiv) ?dd_spec => + let gen_lemma2_2 := constr:(gen_lemma2_1 cdiv dd_spec) in + match s_spec with + | @mkhypo (sign_theory _ _ ?get_sign) ?ss_spec => + let lemma2 := constr:(gen_lemma2_2 get_sign ss_spec) in + let lemma1 := + constr:(ring_correct set ext_r arth morph pp_spec dd_spec) in + fun f => f arth ext_r morph lemma1 lemma2 + | _ => fail 4 "ring: bad sign specification" + end + | _ => fail 3 "ring: bad coefficiant division specification" + end + | _ => fail 2 "ring: bad power specification" + end + | _ => fail 1 "ring internal error: ring_lemmas, please report" + end). + +(* Tactic for constant *) +Ltac isnatcst t := + match t with + O => constr:true + | S ?p => isnatcst p + | _ => constr:false + end. + +Ltac isPcst t := + match t with + | xI ?p => isPcst p + | xO ?p => isPcst p + | xH => constr:true + (* nat -> positive *) + | P_of_succ_nat ?n => isnatcst n + | _ => constr:false + end. + +Ltac isNcst t := + match t with + N0 => constr:true + | Npos ?p => isPcst p + | _ => constr:false + end. + +Ltac isZcst t := + match t with + Z0 => constr:true + | Zpos ?p => isPcst p + | Zneg ?p => isPcst p + (* injection nat -> Z *) + | Z_of_nat ?n => isnatcst n + (* injection N -> Z *) + | Z_of_N ?n => isNcst n + (* *) + | _ => constr:false + end. + + + + + diff --git a/plugins/setoid_ring/NArithRing.v b/plugins/setoid_ring/NArithRing.v new file mode 100644 index 00000000..0ba519fd --- /dev/null +++ b/plugins/setoid_ring/NArithRing.v @@ -0,0 +1,21 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* t + | _ => constr:NotConstant + end. + +Add Ring Nr : Nth (decidable Neq_bool_ok, constants [Ncst]). diff --git a/plugins/setoid_ring/RealField.v b/plugins/setoid_ring/RealField.v new file mode 100644 index 00000000..56473adb --- /dev/null +++ b/plugins/setoid_ring/RealField.v @@ -0,0 +1,134 @@ +Require Import Nnat. +Require Import ArithRing. +Require Export Ring Field. +Require Import Rdefinitions. +Require Import Rpow_def. +Require Import Raxioms. + +Open Local Scope R_scope. + +Lemma RTheory : ring_theory 0 1 Rplus Rmult Rminus Ropp (eq (A:=R)). +Proof. +constructor. + intro; apply Rplus_0_l. + exact Rplus_comm. + symmetry in |- *; apply Rplus_assoc. + intro; apply Rmult_1_l. + exact Rmult_comm. + symmetry in |- *; apply Rmult_assoc. + intros m n p. + rewrite Rmult_comm in |- *. + rewrite (Rmult_comm n p) in |- *. + rewrite (Rmult_comm m p) in |- *. + apply Rmult_plus_distr_l. + reflexivity. + exact Rplus_opp_r. +Qed. + +Lemma Rfield : field_theory 0 1 Rplus Rmult Rminus Ropp Rdiv Rinv (eq(A:=R)). +Proof. +constructor. + exact RTheory. + exact R1_neq_R0. + reflexivity. + exact Rinv_l. +Qed. + +Lemma Rlt_n_Sn : forall x, x < x + 1. +Proof. +intro. +elim archimed with x; intros. +destruct H0. + apply Rlt_trans with (IZR (up x)); trivial. + replace (IZR (up x)) with (x + (IZR (up x) - x))%R. + apply Rplus_lt_compat_l; trivial. + unfold Rminus in |- *. + rewrite (Rplus_comm (IZR (up x)) (- x)) in |- *. + rewrite <- Rplus_assoc in |- *. + rewrite Rplus_opp_r in |- *. + apply Rplus_0_l. + elim H0. + unfold Rminus in |- *. + rewrite (Rplus_comm (IZR (up x)) (- x)) in |- *. + rewrite <- Rplus_assoc in |- *. + rewrite Rplus_opp_r in |- *. + rewrite Rplus_0_l in |- *; trivial. +Qed. + +Notation Rset := (Eqsth R). +Notation Rext := (Eq_ext Rplus Rmult Ropp). + +Lemma Rlt_0_2 : 0 < 2. +apply Rlt_trans with (0 + 1). + apply Rlt_n_Sn. + rewrite Rplus_comm in |- *. + apply Rplus_lt_compat_l. + replace 1 with (0 + 1). + apply Rlt_n_Sn. + apply Rplus_0_l. +Qed. + +Lemma Rgen_phiPOS : forall x, InitialRing.gen_phiPOS1 1 Rplus Rmult x > 0. +unfold Rgt in |- *. +induction x; simpl in |- *; intros. + apply Rlt_trans with (1 + 0). + rewrite Rplus_comm in |- *. + apply Rlt_n_Sn. + apply Rplus_lt_compat_l. + rewrite <- (Rmul_0_l Rset Rext RTheory 2) in |- *. + rewrite Rmult_comm in |- *. + apply Rmult_lt_compat_l. + apply Rlt_0_2. + trivial. + rewrite <- (Rmul_0_l Rset Rext RTheory 2) in |- *. + rewrite Rmult_comm in |- *. + apply Rmult_lt_compat_l. + apply Rlt_0_2. + trivial. + replace 1 with (0 + 1). + apply Rlt_n_Sn. + apply Rplus_0_l. +Qed. + + +Lemma Rgen_phiPOS_not_0 : + forall x, InitialRing.gen_phiPOS1 1 Rplus Rmult x <> 0. +red in |- *; intros. +specialize (Rgen_phiPOS x). +rewrite H in |- *; intro. +apply (Rlt_asym 0 0); trivial. +Qed. + +Lemma Zeq_bool_complete : forall x y, + InitialRing.gen_phiZ 0%R 1%R Rplus Rmult Ropp x = + InitialRing.gen_phiZ 0%R 1%R Rplus Rmult Ropp y -> + Zeq_bool x y = true. +Proof gen_phiZ_complete Rset Rext Rfield Rgen_phiPOS_not_0. + +Lemma Rdef_pow_add : forall (x:R) (n m:nat), pow x (n + m) = pow x n * pow x m. +Proof. + intros x n; elim n; simpl in |- *; auto with real. + intros n0 H' m; rewrite H'; auto with real. +Qed. + +Lemma R_power_theory : power_theory 1%R Rmult (eq (A:=R)) nat_of_N pow. +Proof. + constructor. destruct n. reflexivity. + simpl. induction p;simpl. + rewrite ZL6. rewrite Rdef_pow_add;rewrite IHp. reflexivity. + unfold nat_of_P;simpl;rewrite ZL6;rewrite Rdef_pow_add;rewrite IHp;trivial. + rewrite Rmult_comm;apply Rmult_1_l. +Qed. + +Ltac Rpow_tac t := + match isnatcst t with + | false => constr:(InitialRing.NotConstant) + | _ => constr:(N_of_nat t) + end. + +Add Field RField : Rfield + (completeness Zeq_bool_complete, power_tac R_power_theory [Rpow_tac]). + + + + diff --git a/plugins/setoid_ring/Ring.v b/plugins/setoid_ring/Ring.v new file mode 100644 index 00000000..d01b1625 --- /dev/null +++ b/plugins/setoid_ring/Ring.v @@ -0,0 +1,44 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* b) (eq(A:=bool)). +split; simpl in |- *. +destruct x; reflexivity. +destruct x; destruct y; reflexivity. +destruct x; destruct y; destruct z; reflexivity. +reflexivity. +destruct x; destruct y; reflexivity. +destruct x; destruct y; reflexivity. +destruct x; destruct y; destruct z; reflexivity. +reflexivity. +destruct x; reflexivity. +Qed. + +Definition bool_eq (b1 b2:bool) := + if b1 then b2 else negb b2. + +Lemma bool_eq_ok : forall b1 b2, bool_eq b1 b2 = true -> b1 = b2. +destruct b1; destruct b2; auto. +Qed. + +Ltac bool_cst t := + let t := eval hnf in t in + match t with + true => constr:true + | false => constr:false + | _ => constr:NotConstant + end. + +Add Ring bool_ring : BoolTheory (decidable bool_eq_ok, constants [bool_cst]). diff --git a/plugins/setoid_ring/Ring_base.v b/plugins/setoid_ring/Ring_base.v new file mode 100644 index 00000000..fd9dd8d0 --- /dev/null +++ b/plugins/setoid_ring/Ring_base.v @@ -0,0 +1,17 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* A -> A. +Variable Amult : A -> A -> A. +Variable Aone : A. +Variable Azero : A. +Variable Aopp : A -> A. +Variable Aeq : A -> A -> bool. +Variable R : Ring_Theory Aplus Amult Aone Azero Aopp Aeq. + +Let Aminus := fun x y => Aplus x (Aopp y). + +Lemma ring_equiv1 : + ring_theory Azero Aone Aplus Amult Aminus Aopp (eq (A:=A)). +Proof. +destruct R. +split; eauto. +Qed. + +End Old2New. + +Section New2OldRing. + Variable R : Type. + Variable (rO rI : R) (radd rmul rsub: R->R->R) (ropp : R -> R). + Variable Rth : ring_theory rO rI radd rmul rsub ropp (eq (A:=R)). + + Variable reqb : R -> R -> bool. + Variable reqb_ok : forall x y, reqb x y = true -> x = y. + + Lemma ring_equiv2 : + Ring_Theory radd rmul rI rO ropp reqb. +Proof. +elim Rth; intros; constructor; eauto. +intros. +apply reqb_ok. +destruct (reqb x y); trivial; intros. +elim H. +Qed. + + Definition default_eqb : R -> R -> bool := fun x y => false. + Lemma default_eqb_ok : forall x y, default_eqb x y = true -> x = y. +Proof. +discriminate 1. +Qed. + +End New2OldRing. + +Section New2OldSemiRing. + Variable R : Type. + Variable (rO rI : R) (radd rmul: R->R->R). + Variable SRth : semi_ring_theory rO rI radd rmul (eq (A:=R)). + + Variable reqb : R -> R -> bool. + Variable reqb_ok : forall x y, reqb x y = true -> x = y. + + Lemma sring_equiv2 : + Semi_Ring_Theory radd rmul rI rO reqb. +Proof. +elim SRth; intros; constructor; eauto. +intros. +apply reqb_ok. +destruct (reqb x y); trivial; intros. +elim H. +Qed. + +End New2OldSemiRing. diff --git a/plugins/setoid_ring/Ring_polynom.v b/plugins/setoid_ring/Ring_polynom.v new file mode 100644 index 00000000..faa83ded --- /dev/null +++ b/plugins/setoid_ring/Ring_polynom.v @@ -0,0 +1,1781 @@ +(************************************************************************) +(* V * The Coq Proof Assistant / The Coq Development Team *) +(* R->R) (ropp : R->R). + Variable req : R -> R -> Prop. + + (* Ring properties *) + Variable Rsth : Setoid_Theory R req. + Variable Reqe : ring_eq_ext radd rmul ropp req. + Variable ARth : almost_ring_theory rO rI radd rmul rsub ropp req. + + (* Coefficients *) + Variable C: Type. + Variable (cO cI: C) (cadd cmul csub : C->C->C) (copp : C->C). + Variable ceqb : C->C->bool. + Variable phi : C -> R. + Variable CRmorph : ring_morph rO rI radd rmul rsub ropp req + cO cI cadd cmul csub copp ceqb phi. + + (* Power coefficients *) + Variable Cpow : Set. + Variable Cp_phi : N -> Cpow. + Variable rpow : R -> Cpow -> R. + Variable pow_th : power_theory rI rmul req Cp_phi rpow. + + (* division is ok *) + Variable cdiv: C -> C -> C * C. + Variable div_th: div_theory req cadd cmul phi cdiv. + + + (* R notations *) + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Notation "x - y " := (rsub x y). Notation "- x" := (ropp x). + Notation "x == y" := (req x y). + + (* C notations *) + Notation "x +! y" := (cadd x y). Notation "x *! y " := (cmul x y). + Notation "x -! y " := (csub x y). Notation "-! x" := (copp x). + Notation " x ?=! y" := (ceqb x y). Notation "[ x ]" := (phi x). + + (* Useful tactics *) + Add Setoid R req Rsth as R_set1. + Ltac rrefl := gen_reflexivity Rsth. + Add Morphism radd : radd_ext. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext. exact (Ropp_ext Reqe). Qed. + Add Morphism rsub : rsub_ext. exact (ARsub_ext Rsth Reqe ARth). Qed. + Ltac rsimpl := gen_srewrite Rsth Reqe ARth. + Ltac add_push := gen_add_push radd Rsth Reqe ARth. + Ltac mul_push := gen_mul_push rmul Rsth Reqe ARth. + + (* Definition of multivariable polynomials with coefficients in C : + Type [Pol] represents [X1 ... Xn]. + The representation is Horner's where a [n] variable polynomial + (C[X1..Xn]) is seen as a polynomial on [X1] which coefficients + are polynomials with [n-1] variables (C[X2..Xn]). + There are several optimisations to make the repr compacter: + - [Pc c] is the constant polynomial of value c + == c*X1^0*..*Xn^0 + - [Pinj j Q] is a polynomial constant w.r.t the [j] first variables. + variable indices are shifted of j in Q. + == X1^0 *..* Xj^0 * Q{X1 <- Xj+1;..; Xn-j <- Xn} + - [PX P i Q] is an optimised Horner form of P*X^i + Q + with P not the null polynomial + == P * X1^i + Q{X1 <- X2; ..; Xn-1 <- Xn} + + In addition: + - polynomials of the form (PX (PX P i (Pc 0)) j Q) are forbidden + since they can be represented by the simpler form (PX P (i+j) Q) + - (Pinj i (Pinj j P)) is (Pinj (i+j) P) + - (Pinj i (Pc c)) is (Pc c) + *) + + Inductive Pol : Type := + | Pc : C -> Pol + | Pinj : positive -> Pol -> Pol + | PX : Pol -> positive -> Pol -> Pol. + + Definition P0 := Pc cO. + Definition P1 := Pc cI. + + Fixpoint Peq (P P' : Pol) {struct P'} : bool := + match P, P' with + | Pc c, Pc c' => c ?=! c' + | Pinj j Q, Pinj j' Q' => + match Pcompare j j' Eq with + | Eq => Peq Q Q' + | _ => false + end + | PX P i Q, PX P' i' Q' => + match Pcompare i i' Eq with + | Eq => if Peq P P' then Peq Q Q' else false + | _ => false + end + | _, _ => false + end. + + Notation " P ?== P' " := (Peq P P'). + + Definition mkPinj j P := + match P with + | Pc _ => P + | Pinj j' Q => Pinj ((j + j'):positive) Q + | _ => Pinj j P + end. + + Definition mkPinj_pred j P:= + match j with + | xH => P + | xO j => Pinj (Pdouble_minus_one j) P + | xI j => Pinj (xO j) P + end. + + Definition mkPX P i Q := + match P with + | Pc c => if c ?=! cO then mkPinj xH Q else PX P i Q + | Pinj _ _ => PX P i Q + | PX P' i' Q' => if Q' ?== P0 then PX P' (i' + i) Q else PX P i Q + end. + + Definition mkXi i := PX P1 i P0. + + Definition mkX := mkXi 1. + + (** Opposite of addition *) + + Fixpoint Popp (P:Pol) : Pol := + match P with + | Pc c => Pc (-! c) + | Pinj j Q => Pinj j (Popp Q) + | PX P i Q => PX (Popp P) i (Popp Q) + end. + + Notation "-- P" := (Popp P). + + (** Addition et subtraction *) + + Fixpoint PaddC (P:Pol) (c:C) {struct P} : Pol := + match P with + | Pc c1 => Pc (c1 +! c) + | Pinj j Q => Pinj j (PaddC Q c) + | PX P i Q => PX P i (PaddC Q c) + end. + + Fixpoint PsubC (P:Pol) (c:C) {struct P} : Pol := + match P with + | Pc c1 => Pc (c1 -! c) + | Pinj j Q => Pinj j (PsubC Q c) + | PX P i Q => PX P i (PsubC Q c) + end. + + Section PopI. + + Variable Pop : Pol -> Pol -> Pol. + Variable Q : Pol. + + Fixpoint PaddI (j:positive) (P:Pol){struct P} : Pol := + match P with + | Pc c => mkPinj j (PaddC Q c) + | Pinj j' Q' => + match ZPminus j' j with + | Zpos k => mkPinj j (Pop (Pinj k Q') Q) + | Z0 => mkPinj j (Pop Q' Q) + | Zneg k => mkPinj j' (PaddI k Q') + end + | PX P i Q' => + match j with + | xH => PX P i (Pop Q' Q) + | xO j => PX P i (PaddI (Pdouble_minus_one j) Q') + | xI j => PX P i (PaddI (xO j) Q') + end + end. + + Fixpoint PsubI (j:positive) (P:Pol){struct P} : Pol := + match P with + | Pc c => mkPinj j (PaddC (--Q) c) + | Pinj j' Q' => + match ZPminus j' j with + | Zpos k => mkPinj j (Pop (Pinj k Q') Q) + | Z0 => mkPinj j (Pop Q' Q) + | Zneg k => mkPinj j' (PsubI k Q') + end + | PX P i Q' => + match j with + | xH => PX P i (Pop Q' Q) + | xO j => PX P i (PsubI (Pdouble_minus_one j) Q') + | xI j => PX P i (PsubI (xO j) Q') + end + end. + + Variable P' : Pol. + + Fixpoint PaddX (i':positive) (P:Pol) {struct P} : Pol := + match P with + | Pc c => PX P' i' P + | Pinj j Q' => + match j with + | xH => PX P' i' Q' + | xO j => PX P' i' (Pinj (Pdouble_minus_one j) Q') + | xI j => PX P' i' (Pinj (xO j) Q') + end + | PX P i Q' => + match ZPminus i i' with + | Zpos k => mkPX (Pop (PX P k P0) P') i' Q' + | Z0 => mkPX (Pop P P') i Q' + | Zneg k => mkPX (PaddX k P) i Q' + end + end. + + Fixpoint PsubX (i':positive) (P:Pol) {struct P} : Pol := + match P with + | Pc c => PX (--P') i' P + | Pinj j Q' => + match j with + | xH => PX (--P') i' Q' + | xO j => PX (--P') i' (Pinj (Pdouble_minus_one j) Q') + | xI j => PX (--P') i' (Pinj (xO j) Q') + end + | PX P i Q' => + match ZPminus i i' with + | Zpos k => mkPX (Pop (PX P k P0) P') i' Q' + | Z0 => mkPX (Pop P P') i Q' + | Zneg k => mkPX (PsubX k P) i Q' + end + end. + + + End PopI. + + Fixpoint Padd (P P': Pol) {struct P'} : Pol := + match P' with + | Pc c' => PaddC P c' + | Pinj j' Q' => PaddI Padd Q' j' P + | PX P' i' Q' => + match P with + | Pc c => PX P' i' (PaddC Q' c) + | Pinj j Q => + match j with + | xH => PX P' i' (Padd Q Q') + | xO j => PX P' i' (Padd (Pinj (Pdouble_minus_one j) Q) Q') + | xI j => PX P' i' (Padd (Pinj (xO j) Q) Q') + end + | PX P i Q => + match ZPminus i i' with + | Zpos k => mkPX (Padd (PX P k P0) P') i' (Padd Q Q') + | Z0 => mkPX (Padd P P') i (Padd Q Q') + | Zneg k => mkPX (PaddX Padd P' k P) i (Padd Q Q') + end + end + end. + Notation "P ++ P'" := (Padd P P'). + + Fixpoint Psub (P P': Pol) {struct P'} : Pol := + match P' with + | Pc c' => PsubC P c' + | Pinj j' Q' => PsubI Psub Q' j' P + | PX P' i' Q' => + match P with + | Pc c => PX (--P') i' (*(--(PsubC Q' c))*) (PaddC (--Q') c) + | Pinj j Q => + match j with + | xH => PX (--P') i' (Psub Q Q') + | xO j => PX (--P') i' (Psub (Pinj (Pdouble_minus_one j) Q) Q') + | xI j => PX (--P') i' (Psub (Pinj (xO j) Q) Q') + end + | PX P i Q => + match ZPminus i i' with + | Zpos k => mkPX (Psub (PX P k P0) P') i' (Psub Q Q') + | Z0 => mkPX (Psub P P') i (Psub Q Q') + | Zneg k => mkPX (PsubX Psub P' k P) i (Psub Q Q') + end + end + end. + Notation "P -- P'" := (Psub P P'). + + (** Multiplication *) + + Fixpoint PmulC_aux (P:Pol) (c:C) {struct P} : Pol := + match P with + | Pc c' => Pc (c' *! c) + | Pinj j Q => mkPinj j (PmulC_aux Q c) + | PX P i Q => mkPX (PmulC_aux P c) i (PmulC_aux Q c) + end. + + Definition PmulC P c := + if c ?=! cO then P0 else + if c ?=! cI then P else PmulC_aux P c. + + Section PmulI. + Variable Pmul : Pol -> Pol -> Pol. + Variable Q : Pol. + Fixpoint PmulI (j:positive) (P:Pol) {struct P} : Pol := + match P with + | Pc c => mkPinj j (PmulC Q c) + | Pinj j' Q' => + match ZPminus j' j with + | Zpos k => mkPinj j (Pmul (Pinj k Q') Q) + | Z0 => mkPinj j (Pmul Q' Q) + | Zneg k => mkPinj j' (PmulI k Q') + end + | PX P' i' Q' => + match j with + | xH => mkPX (PmulI xH P') i' (Pmul Q' Q) + | xO j' => mkPX (PmulI j P') i' (PmulI (Pdouble_minus_one j') Q') + | xI j' => mkPX (PmulI j P') i' (PmulI (xO j') Q') + end + end. + + End PmulI. +(* A symmetric version of the multiplication *) + + Fixpoint Pmul (P P'' : Pol) {struct P''} : Pol := + match P'' with + | Pc c => PmulC P c + | Pinj j' Q' => PmulI Pmul Q' j' P + | PX P' i' Q' => + match P with + | Pc c => PmulC P'' c + | Pinj j Q => + let QQ' := + match j with + | xH => Pmul Q Q' + | xO j => Pmul (Pinj (Pdouble_minus_one j) Q) Q' + | xI j => Pmul (Pinj (xO j) Q) Q' + end in + mkPX (Pmul P P') i' QQ' + | PX P i Q=> + let QQ' := Pmul Q Q' in + let PQ' := PmulI Pmul Q' xH P in + let QP' := Pmul (mkPinj xH Q) P' in + let PP' := Pmul P P' in + (mkPX (mkPX PP' i P0 ++ QP') i' P0) ++ mkPX PQ' i QQ' + end + end. + +(* Non symmetric *) +(* + Fixpoint Pmul_aux (P P' : Pol) {struct P'} : Pol := + match P' with + | Pc c' => PmulC P c' + | Pinj j' Q' => PmulI Pmul_aux Q' j' P + | PX P' i' Q' => + (mkPX (Pmul_aux P P') i' P0) ++ (PmulI Pmul_aux Q' xH P) + end. + + Definition Pmul P P' := + match P with + | Pc c => PmulC P' c + | Pinj j Q => PmulI Pmul_aux Q j P' + | PX P i Q => + (mkPX (Pmul_aux P P') i P0) ++ (PmulI Pmul_aux Q xH P') + end. +*) + Notation "P ** P'" := (Pmul P P'). + + Fixpoint Psquare (P:Pol) : Pol := + match P with + | Pc c => Pc (c *! c) + | Pinj j Q => Pinj j (Psquare Q) + | PX P i Q => + let twoPQ := Pmul P (mkPinj xH (PmulC Q (cI +! cI))) in + let Q2 := Psquare Q in + let P2 := Psquare P in + mkPX (mkPX P2 i P0 ++ twoPQ) i Q2 + end. + + (** Monomial **) + + Inductive Mon: Set := + mon0: Mon + | zmon: positive -> Mon -> Mon + | vmon: positive -> Mon -> Mon. + + Fixpoint Mphi(l:list R) (M: Mon) {struct M} : R := + match M with + mon0 => rI + | zmon j M1 => Mphi (jump j l) M1 + | vmon i M1 => + let x := hd 0 l in + let xi := pow_pos rmul x i in + (Mphi (tail l) M1) * xi + end. + + Definition mkZmon j M := + match M with mon0 => mon0 | _ => zmon j M end. + + Definition zmon_pred j M := + match j with xH => M | _ => mkZmon (Ppred j) M end. + + Definition mkVmon i M := + match M with + | mon0 => vmon i mon0 + | zmon j m => vmon i (zmon_pred j m) + | vmon i' m => vmon (i+i') m + end. + + Fixpoint CFactor (P: Pol) (c: C) {struct P}: Pol * Pol := + match P with + | Pc c1 => let (q,r) := cdiv c1 c in (Pc r, Pc q) + | Pinj j1 P1 => + let (R,S) := CFactor P1 c in + (mkPinj j1 R, mkPinj j1 S) + | PX P1 i Q1 => + let (R1, S1) := CFactor P1 c in + let (R2, S2) := CFactor Q1 c in + (mkPX R1 i R2, mkPX S1 i S2) + end. + + Fixpoint MFactor (P: Pol) (c: C) (M: Mon) {struct P}: Pol * Pol := + match P, M with + _, mon0 => + if (ceqb c cI) then (Pc cO, P) else +(* if (ceqb c (copp cI)) then (Pc cO, Popp P) else Not in almost ring *) + CFactor P c + | Pc _, _ => (P, Pc cO) + | Pinj j1 P1, zmon j2 M1 => + match (j1 ?= j2) Eq with + Eq => let (R,S) := MFactor P1 c M1 in + (mkPinj j1 R, mkPinj j1 S) + | Lt => let (R,S) := MFactor P1 c (zmon (j2 - j1) M1) in + (mkPinj j1 R, mkPinj j1 S) + | Gt => (P, Pc cO) + end + | Pinj _ _, vmon _ _ => (P, Pc cO) + | PX P1 i Q1, zmon j M1 => + let M2 := zmon_pred j M1 in + let (R1, S1) := MFactor P1 c M in + let (R2, S2) := MFactor Q1 c M2 in + (mkPX R1 i R2, mkPX S1 i S2) + | PX P1 i Q1, vmon j M1 => + match (i ?= j) Eq with + Eq => let (R1,S1) := MFactor P1 c (mkZmon xH M1) in + (mkPX R1 i Q1, S1) + | Lt => let (R1,S1) := MFactor P1 c (vmon (j - i) M1) in + (mkPX R1 i Q1, S1) + | Gt => let (R1,S1) := MFactor P1 c (mkZmon xH M1) in + (mkPX R1 i Q1, mkPX S1 (i-j) (Pc cO)) + end + end. + + Definition POneSubst (P1: Pol) (cM1: C * Mon) (P2: Pol): option Pol := + let (c,M1) := cM1 in + let (Q1,R1) := MFactor P1 c M1 in + match R1 with + (Pc c) => if c ?=! cO then None + else Some (Padd Q1 (Pmul P2 R1)) + | _ => Some (Padd Q1 (Pmul P2 R1)) + end. + + Fixpoint PNSubst1 (P1: Pol) (cM1: C * Mon) (P2: Pol) (n: nat) {struct n}: Pol := + match POneSubst P1 cM1 P2 with + Some P3 => match n with S n1 => PNSubst1 P3 cM1 P2 n1 | _ => P3 end + | _ => P1 + end. + + Definition PNSubst (P1: Pol) (cM1: C * Mon) (P2: Pol) (n: nat): option Pol := + match POneSubst P1 cM1 P2 with + Some P3 => match n with S n1 => Some (PNSubst1 P3 cM1 P2 n1) | _ => None end + | _ => None + end. + + Fixpoint PSubstL1 (P1: Pol) (LM1: list ((C * Mon) * Pol)) (n: nat) {struct LM1}: + Pol := + match LM1 with + cons (M1,P2) LM2 => PSubstL1 (PNSubst1 P1 M1 P2 n) LM2 n + | _ => P1 + end. + + Fixpoint PSubstL (P1: Pol) (LM1: list ((C * Mon) * Pol)) (n: nat) {struct LM1}: option Pol := + match LM1 with + cons (M1,P2) LM2 => + match PNSubst P1 M1 P2 n with + Some P3 => Some (PSubstL1 P3 LM2 n) + | None => PSubstL P1 LM2 n + end + | _ => None + end. + + Fixpoint PNSubstL (P1: Pol) (LM1: list ((C * Mon) * Pol)) (m n: nat) {struct m}: Pol := + match PSubstL P1 LM1 n with + Some P3 => match m with S m1 => PNSubstL P3 LM1 m1 n | _ => P3 end + | _ => P1 + end. + + (** Evaluation of a polynomial towards R *) + + Fixpoint Pphi(l:list R) (P:Pol) {struct P} : R := + match P with + | Pc c => [c] + | Pinj j Q => Pphi (jump j l) Q + | PX P i Q => + let x := hd 0 l in + let xi := pow_pos rmul x i in + (Pphi l P) * xi + (Pphi (tail l) Q) + end. + + Reserved Notation "P @ l " (at level 10, no associativity). + Notation "P @ l " := (Pphi l P). + (** Proofs *) + Lemma ZPminus_spec : forall x y, + match ZPminus x y with + | Z0 => x = y + | Zpos k => x = (y + k)%positive + | Zneg k => y = (x + k)%positive + end. + Proof. + induction x;destruct y. + replace (ZPminus (xI x) (xI y)) with (Zdouble (ZPminus x y));trivial. + assert (H := IHx y);destruct (ZPminus x y);unfold Zdouble;rewrite H;trivial. + replace (ZPminus (xI x) (xO y)) with (Zdouble_plus_one (ZPminus x y));trivial. + assert (H := IHx y);destruct (ZPminus x y);unfold Zdouble_plus_one;rewrite H;trivial. + apply Pplus_xI_double_minus_one. + simpl;trivial. + replace (ZPminus (xO x) (xI y)) with (Zdouble_minus_one (ZPminus x y));trivial. + assert (H := IHx y);destruct (ZPminus x y);unfold Zdouble_minus_one;rewrite H;trivial. + apply Pplus_xI_double_minus_one. + replace (ZPminus (xO x) (xO y)) with (Zdouble (ZPminus x y));trivial. + assert (H := IHx y);destruct (ZPminus x y);unfold Zdouble;rewrite H;trivial. + replace (ZPminus (xO x) xH) with (Zpos (Pdouble_minus_one x));trivial. + rewrite <- Pplus_one_succ_l. + rewrite Psucc_o_double_minus_one_eq_xO;trivial. + replace (ZPminus xH (xI y)) with (Zneg (xO y));trivial. + replace (ZPminus xH (xO y)) with (Zneg (Pdouble_minus_one y));trivial. + rewrite <- Pplus_one_succ_l. + rewrite Psucc_o_double_minus_one_eq_xO;trivial. + simpl;trivial. + Qed. + + Lemma Peq_ok : forall P P', + (P ?== P') = true -> forall l, P@l == P'@ l. + Proof. + induction P;destruct P';simpl;intros;try discriminate;trivial. + apply (morph_eq CRmorph);trivial. + assert (H1 := Pcompare_Eq_eq p p0); destruct ((p ?= p0)%positive Eq); + try discriminate H. + rewrite (IHP P' H); rewrite H1;trivial;rrefl. + assert (H1 := Pcompare_Eq_eq p p0); destruct ((p ?= p0)%positive Eq); + try discriminate H. + rewrite H1;trivial. clear H1. + assert (H1 := IHP1 P'1);assert (H2 := IHP2 P'2); + destruct (P2 ?== P'1);[destruct (P3 ?== P'2); [idtac|discriminate H] + |discriminate H]. + rewrite (H1 H);rewrite (H2 H);rrefl. + Qed. + + Lemma Pphi0 : forall l, P0@l == 0. + Proof. + intros;simpl;apply (morph0 CRmorph). + Qed. + + Lemma Pphi1 : forall l, P1@l == 1. + Proof. + intros;simpl;apply (morph1 CRmorph). + Qed. + + Lemma mkPinj_ok : forall j l P, (mkPinj j P)@l == P@(jump j l). + Proof. + intros j l p;destruct p;simpl;rsimpl. + rewrite <-jump_Pplus;rewrite Pplus_comm;rrefl. + Qed. + + Let pow_pos_Pplus := + pow_pos_Pplus rmul Rsth Reqe.(Rmul_ext) ARth.(ARmul_comm) ARth.(ARmul_assoc). + + Lemma mkPX_ok : forall l P i Q, + (mkPX P i Q)@l == P@l*(pow_pos rmul (hd 0 l) i) + Q@(tail l). + Proof. + intros l P i Q;unfold mkPX. + destruct P;try (simpl;rrefl). + assert (H := morph_eq CRmorph c cO);destruct (c ?=! cO);simpl;try rrefl. + rewrite (H (refl_equal true));rewrite (morph0 CRmorph). + rewrite mkPinj_ok;rsimpl;simpl;rrefl. + assert (H := @Peq_ok P3 P0);destruct (P3 ?== P0);simpl;try rrefl. + rewrite (H (refl_equal true));trivial. + rewrite Pphi0. rewrite pow_pos_Pplus;rsimpl. + Qed. + + Ltac Esimpl := + repeat (progress ( + match goal with + | |- context [?P@?l] => + match P with + | P0 => rewrite (Pphi0 l) + | P1 => rewrite (Pphi1 l) + | (mkPinj ?j ?P) => rewrite (mkPinj_ok j l P) + | (mkPX ?P ?i ?Q) => rewrite (mkPX_ok l P i Q) + end + | |- context [[?c]] => + match c with + | cO => rewrite (morph0 CRmorph) + | cI => rewrite (morph1 CRmorph) + | ?x +! ?y => rewrite ((morph_add CRmorph) x y) + | ?x *! ?y => rewrite ((morph_mul CRmorph) x y) + | ?x -! ?y => rewrite ((morph_sub CRmorph) x y) + | -! ?x => rewrite ((morph_opp CRmorph) x) + end + end)); + rsimpl; simpl. + + Lemma PaddC_ok : forall c P l, (PaddC P c)@l == P@l + [c]. + Proof. + induction P;simpl;intros;Esimpl;trivial. + rewrite IHP2;rsimpl. + Qed. + + Lemma PsubC_ok : forall c P l, (PsubC P c)@l == P@l - [c]. + Proof. + induction P;simpl;intros. + Esimpl. + rewrite IHP;rsimpl. + rewrite IHP2;rsimpl. + Qed. + + Lemma PmulC_aux_ok : forall c P l, (PmulC_aux P c)@l == P@l * [c]. + Proof. + induction P;simpl;intros;Esimpl;trivial. + rewrite IHP1;rewrite IHP2;rsimpl. + mul_push ([c]);rrefl. + Qed. + + Lemma PmulC_ok : forall c P l, (PmulC P c)@l == P@l * [c]. + Proof. + intros c P l; unfold PmulC. + assert (H:= morph_eq CRmorph c cO);destruct (c ?=! cO). + rewrite (H (refl_equal true));Esimpl. + assert (H1:= morph_eq CRmorph c cI);destruct (c ?=! cI). + rewrite (H1 (refl_equal true));Esimpl. + apply PmulC_aux_ok. + Qed. + + Lemma Popp_ok : forall P l, (--P)@l == - P@l. + Proof. + induction P;simpl;intros. + Esimpl. + apply IHP. + rewrite IHP1;rewrite IHP2;rsimpl. + Qed. + + Ltac Esimpl2 := + Esimpl; + repeat (progress ( + match goal with + | |- context [(PaddC ?P ?c)@?l] => rewrite (PaddC_ok c P l) + | |- context [(PsubC ?P ?c)@?l] => rewrite (PsubC_ok c P l) + | |- context [(PmulC ?P ?c)@?l] => rewrite (PmulC_ok c P l) + | |- context [(--?P)@?l] => rewrite (Popp_ok P l) + end)); Esimpl. + + Lemma Padd_ok : forall P' P l, (P ++ P')@l == P@l + P'@l. + Proof. + induction P';simpl;intros;Esimpl2. + generalize P p l;clear P p l. + induction P;simpl;intros. + Esimpl2;apply (ARadd_comm ARth). + assert (H := ZPminus_spec p p0);destruct (ZPminus p p0). + rewrite H;Esimpl. rewrite IHP';rrefl. + rewrite H;Esimpl. rewrite IHP';Esimpl. + rewrite <- jump_Pplus;rewrite Pplus_comm;rrefl. + rewrite H;Esimpl. rewrite IHP. + rewrite <- jump_Pplus;rewrite Pplus_comm;rrefl. + destruct p0;simpl. + rewrite IHP2;simpl;rsimpl. + rewrite IHP2;simpl. + rewrite jump_Pdouble_minus_one;rsimpl. + rewrite IHP';rsimpl. + destruct P;simpl. + Esimpl2;add_push [c];rrefl. + destruct p0;simpl;Esimpl2. + rewrite IHP'2;simpl. + rsimpl;add_push (P'1@l * (pow_pos rmul (hd 0 l) p));rrefl. + rewrite IHP'2;simpl. + rewrite jump_Pdouble_minus_one;rsimpl;add_push (P'1@l * (pow_pos rmul (hd 0 l) p));rrefl. + rewrite IHP'2;rsimpl. add_push (P @ (tail l));rrefl. + assert (H := ZPminus_spec p0 p);destruct (ZPminus p0 p);Esimpl2. + rewrite IHP'1;rewrite IHP'2;rsimpl. + add_push (P3 @ (tail l));rewrite H;rrefl. + rewrite IHP'1;rewrite IHP'2;simpl;Esimpl. + rewrite H;rewrite Pplus_comm. + rewrite pow_pos_Pplus;rsimpl. + add_push (P3 @ (tail l));rrefl. + assert (forall P k l, + (PaddX Padd P'1 k P) @ l == P@l + P'1@l * pow_pos rmul (hd 0 l) k). + induction P;simpl;intros;try apply (ARadd_comm ARth). + destruct p2;simpl;try apply (ARadd_comm ARth). + rewrite jump_Pdouble_minus_one;apply (ARadd_comm ARth). + assert (H1 := ZPminus_spec p2 k);destruct (ZPminus p2 k);Esimpl2. + rewrite IHP'1;rsimpl; rewrite H1;add_push (P5 @ (tail l0));rrefl. + rewrite IHP'1;simpl;Esimpl. + rewrite H1;rewrite Pplus_comm. + rewrite pow_pos_Pplus;simpl;Esimpl. + add_push (P5 @ (tail l0));rrefl. + rewrite IHP1;rewrite H1;rewrite Pplus_comm. + rewrite pow_pos_Pplus;simpl;rsimpl. + add_push (P5 @ (tail l0));rrefl. + rewrite H0;rsimpl. + add_push (P3 @ (tail l)). + rewrite H;rewrite Pplus_comm. + rewrite IHP'2;rewrite pow_pos_Pplus;rsimpl. + add_push (P3 @ (tail l));rrefl. + Qed. + + Lemma Psub_ok : forall P' P l, (P -- P')@l == P@l - P'@l. + Proof. + induction P';simpl;intros;Esimpl2;trivial. + generalize P p l;clear P p l. + induction P;simpl;intros. + Esimpl2;apply (ARadd_comm ARth). + assert (H := ZPminus_spec p p0);destruct (ZPminus p p0). + rewrite H;Esimpl. rewrite IHP';rsimpl. + rewrite H;Esimpl. rewrite IHP';Esimpl. + rewrite <- jump_Pplus;rewrite Pplus_comm;rrefl. + rewrite H;Esimpl. rewrite IHP. + rewrite <- jump_Pplus;rewrite Pplus_comm;rrefl. + destruct p0;simpl. + rewrite IHP2;simpl;rsimpl. + rewrite IHP2;simpl. + rewrite jump_Pdouble_minus_one;rsimpl. + rewrite IHP';rsimpl. + destruct P;simpl. + repeat rewrite Popp_ok;Esimpl2;rsimpl;add_push [c];try rrefl. + destruct p0;simpl;Esimpl2. + rewrite IHP'2;simpl;rsimpl;add_push (P'1@l * (pow_pos rmul (hd 0 l) p));trivial. + add_push (P @ (jump p0 (jump p0 (tail l))));rrefl. + rewrite IHP'2;simpl;rewrite jump_Pdouble_minus_one;rsimpl. + add_push (- (P'1 @ l * pow_pos rmul (hd 0 l) p));rrefl. + rewrite IHP'2;rsimpl;add_push (P @ (tail l));rrefl. + assert (H := ZPminus_spec p0 p);destruct (ZPminus p0 p);Esimpl2. + rewrite IHP'1; rewrite IHP'2;rsimpl. + add_push (P3 @ (tail l));rewrite H;rrefl. + rewrite IHP'1; rewrite IHP'2;rsimpl;simpl;Esimpl. + rewrite H;rewrite Pplus_comm. + rewrite pow_pos_Pplus;rsimpl. + add_push (P3 @ (tail l));rrefl. + assert (forall P k l, + (PsubX Psub P'1 k P) @ l == P@l + - P'1@l * pow_pos rmul (hd 0 l) k). + induction P;simpl;intros. + rewrite Popp_ok;rsimpl;apply (ARadd_comm ARth);trivial. + destruct p2;simpl;rewrite Popp_ok;rsimpl. + apply (ARadd_comm ARth);trivial. + rewrite jump_Pdouble_minus_one;apply (ARadd_comm ARth);trivial. + apply (ARadd_comm ARth);trivial. + assert (H1 := ZPminus_spec p2 k);destruct (ZPminus p2 k);Esimpl2;rsimpl. + rewrite IHP'1;rsimpl;add_push (P5 @ (tail l0));rewrite H1;rrefl. + rewrite IHP'1;rewrite H1;rewrite Pplus_comm. + rewrite pow_pos_Pplus;simpl;Esimpl. + add_push (P5 @ (tail l0));rrefl. + rewrite IHP1;rewrite H1;rewrite Pplus_comm. + rewrite pow_pos_Pplus;simpl;rsimpl. + add_push (P5 @ (tail l0));rrefl. + rewrite H0;rsimpl. + rewrite IHP'2;rsimpl;add_push (P3 @ (tail l)). + rewrite H;rewrite Pplus_comm. + rewrite pow_pos_Pplus;rsimpl. + Qed. +(* Proof for the symmetriv version *) + + Lemma PmulI_ok : + forall P', + (forall (P : Pol) (l : list R), (Pmul P P') @ l == P @ l * P' @ l) -> + forall (P : Pol) (p : positive) (l : list R), + (PmulI Pmul P' p P) @ l == P @ l * P' @ (jump p l). + Proof. + induction P;simpl;intros. + Esimpl2;apply (ARmul_comm ARth). + assert (H1 := ZPminus_spec p p0);destruct (ZPminus p p0);Esimpl2. + rewrite H1; rewrite H;rrefl. + rewrite H1; rewrite H. + rewrite Pplus_comm. + rewrite jump_Pplus;simpl;rrefl. + rewrite H1;rewrite Pplus_comm. + rewrite jump_Pplus;rewrite IHP;rrefl. + destruct p0;Esimpl2. + rewrite IHP1;rewrite IHP2;simpl;rsimpl. + mul_push (pow_pos rmul (hd 0 l) p);rrefl. + rewrite IHP1;rewrite IHP2;simpl;rsimpl. + mul_push (pow_pos rmul (hd 0 l) p); rewrite jump_Pdouble_minus_one;rrefl. + rewrite IHP1;simpl;rsimpl. + mul_push (pow_pos rmul (hd 0 l) p). + rewrite H;rrefl. + Qed. + +(* + Lemma PmulI_ok : + forall P', + (forall (P : Pol) (l : list R), (Pmul_aux P P') @ l == P @ l * P' @ l) -> + forall (P : Pol) (p : positive) (l : list R), + (PmulI Pmul_aux P' p P) @ l == P @ l * P' @ (jump p l). + Proof. + induction P;simpl;intros. + Esimpl2;apply (ARmul_comm ARth). + assert (H1 := ZPminus_spec p p0);destruct (ZPminus p p0);Esimpl2. + rewrite H1; rewrite H;rrefl. + rewrite H1; rewrite H. + rewrite Pplus_comm. + rewrite jump_Pplus;simpl;rrefl. + rewrite H1;rewrite Pplus_comm. + rewrite jump_Pplus;rewrite IHP;rrefl. + destruct p0;Esimpl2. + rewrite IHP1;rewrite IHP2;simpl;rsimpl. + mul_push (pow_pos rmul (hd 0 l) p);rrefl. + rewrite IHP1;rewrite IHP2;simpl;rsimpl. + mul_push (pow_pos rmul (hd 0 l) p); rewrite jump_Pdouble_minus_one;rrefl. + rewrite IHP1;simpl;rsimpl. + mul_push (pow_pos rmul (hd 0 l) p). + rewrite H;rrefl. + Qed. + + Lemma Pmul_aux_ok : forall P' P l,(Pmul_aux P P')@l == P@l * P'@l. + Proof. + induction P';simpl;intros. + Esimpl2;trivial. + apply PmulI_ok;trivial. + rewrite Padd_ok;Esimpl2. + rewrite (PmulI_ok P'2 IHP'2). rewrite IHP'1. rrefl. + Qed. +*) + +(* Proof for the symmetric version *) + Lemma Pmul_ok : forall P P' l, (P**P')@l == P@l * P'@l. + Proof. + intros P P';generalize P;clear P;induction P';simpl;intros. + apply PmulC_ok. apply PmulI_ok;trivial. + destruct P. + rewrite (ARmul_comm ARth);Esimpl2;Esimpl2. + Esimpl2. rewrite IHP'1;Esimpl2. + assert (match p0 with + | xI j => Pinj (xO j) P ** P'2 + | xO j => Pinj (Pdouble_minus_one j) P ** P'2 + | 1 => P ** P'2 + end @ (tail l) == P @ (jump p0 l) * P'2 @ (tail l)). + destruct p0;simpl;rewrite IHP'2;Esimpl. + rewrite jump_Pdouble_minus_one;Esimpl. + rewrite H;Esimpl. + rewrite Padd_ok; Esimpl2. rewrite Padd_ok; Esimpl2. + repeat (rewrite IHP'1 || rewrite IHP'2);simpl. + rewrite PmulI_ok;trivial. + mul_push (P'1@l). simpl. mul_push (P'2 @ (tail l)). Esimpl. + Qed. + +(* +Lemma Pmul_ok : forall P P' l, (P**P')@l == P@l * P'@l. + Proof. + destruct P;simpl;intros. + Esimpl2;apply (ARmul_comm ARth). + rewrite (PmulI_ok P (Pmul_aux_ok P)). + apply (ARmul_comm ARth). + rewrite Padd_ok; Esimpl2. + rewrite (PmulI_ok P3 (Pmul_aux_ok P3));trivial. + rewrite Pmul_aux_ok;mul_push (P' @ l). + rewrite (ARmul_comm ARth (P' @ l));rrefl. + Qed. +*) + + Lemma Psquare_ok : forall P l, (Psquare P)@l == P@l * P@l. + Proof. + induction P;simpl;intros;Esimpl2. + apply IHP. rewrite Padd_ok. rewrite Pmul_ok;Esimpl2. + rewrite IHP1;rewrite IHP2. + mul_push (pow_pos rmul (hd 0 l) p). mul_push (P2@l). + rrefl. + Qed. + + + Lemma mkZmon_ok: forall M j l, + Mphi l (mkZmon j M) == Mphi l (zmon j M). + intros M j l; case M; simpl; intros; rsimpl. + Qed. + + Lemma zmon_pred_ok : forall M j l, + Mphi (tail l) (zmon_pred j M) == Mphi l (zmon j M). + Proof. + destruct j; simpl;intros auto; rsimpl. + rewrite mkZmon_ok;rsimpl. + rewrite mkZmon_ok;simpl. rewrite jump_Pdouble_minus_one; rsimpl. + Qed. + + Lemma mkVmon_ok : forall M i l, Mphi l (mkVmon i M) == Mphi l M*pow_pos rmul (hd 0 l) i. + Proof. + destruct M;simpl;intros;rsimpl. + rewrite zmon_pred_ok;simpl;rsimpl. + rewrite Pplus_comm;rewrite pow_pos_Pplus;rsimpl. + Qed. + + Lemma Mcphi_ok: forall P c l, + let (Q,R) := CFactor P c in + P@l == Q@l + (phi c) * (R@l). + Proof. + intros P; elim P; simpl; auto; clear P. + intros c c1 l; generalize (div_th.(div_eucl_th) c c1); case cdiv. + intros q r H; rewrite H. + Esimpl. + rewrite (ARadd_comm ARth); rsimpl. + intros i P Hrec c l. + generalize (Hrec c (jump i l)); case CFactor. + intros R1 S1; Esimpl; auto. + intros Q1 Qrec i R1 Rrec c l. + generalize (Qrec c l); case CFactor; intros S1 S2 HS. + generalize (Rrec c (tail l)); case CFactor; intros S3 S4 HS1. + rewrite HS; rewrite HS1; Esimpl. + apply (Radd_ext Reqe); rsimpl. + repeat rewrite <- (ARadd_assoc ARth). + apply (Radd_ext Reqe); rsimpl. + rewrite (ARadd_comm ARth); rsimpl. + Qed. + + Lemma Mphi_ok: forall P (cM: C * Mon) l, + let (c,M) := cM in + let (Q,R) := MFactor P c M in + P@l == Q@l + (phi c) * (Mphi l M) * (R@l). + Proof. + intros P; elim P; simpl; auto; clear P. + intros c (c1, M) l; case M; simpl; auto. + assert (H1:= morph_eq CRmorph c1 cI);destruct (c1 ?=! cI). + rewrite (H1 (refl_equal true));Esimpl. + try rewrite (morph0 CRmorph); rsimpl. + generalize (div_th.(div_eucl_th) c c1); case (cdiv c c1). + intros q r H; rewrite H; clear H H1. + Esimpl. + rewrite (ARadd_comm ARth); rsimpl. + intros p m; Esimpl. + intros p m; Esimpl. + intros i P Hrec (c,M) l; case M; simpl; clear M. + assert (H1:= morph_eq CRmorph c cI);destruct (c ?=! cI). + rewrite (H1 (refl_equal true));Esimpl. + Esimpl. + generalize (Mcphi_ok P c (jump i l)); case CFactor. + intros R1 Q1 HH; rewrite HH; Esimpl. + intros j M. + case_eq ((i ?= j) Eq); intros He; simpl. + rewrite (Pcompare_Eq_eq _ _ He). + generalize (Hrec (c, M) (jump j l)); case (MFactor P c M); + simpl; intros P2 Q2 H; repeat rewrite mkPinj_ok; auto. + generalize (Hrec (c, (zmon (j -i) M)) (jump i l)); + case (MFactor P c (zmon (j -i) M)); simpl. + intros P2 Q2 H; repeat rewrite mkPinj_ok; auto. + rewrite <- (Pplus_minus _ _ (ZC2 _ _ He)). + rewrite Pplus_comm; rewrite jump_Pplus; auto. + rewrite (morph0 CRmorph); rsimpl. + intros P2 m; rewrite (morph0 CRmorph); rsimpl. + + intros P2 Hrec1 i Q2 Hrec2 (c, M) l; case M; simpl; auto. + assert (H1:= morph_eq CRmorph c cI);destruct (c ?=! cI). + rewrite (H1 (refl_equal true));Esimpl. + Esimpl. + generalize (Mcphi_ok P2 c l); case CFactor. + intros S1 S2 HS. + generalize (Mcphi_ok Q2 c (tail l)); case CFactor. + intros S3 S4 HS1; Esimpl; rewrite HS; rewrite HS1. + rsimpl. + apply (Radd_ext Reqe); rsimpl. + repeat rewrite <- (ARadd_assoc ARth). + apply (Radd_ext Reqe); rsimpl. + rewrite (ARadd_comm ARth); rsimpl. + intros j M1. + generalize (Hrec1 (c,zmon j M1) l); + case (MFactor P2 c (zmon j M1)). + intros R1 S1 H1. + generalize (Hrec2 (c, zmon_pred j M1) (List.tail l)); + case (MFactor Q2 c (zmon_pred j M1)); simpl. + intros R2 S2 H2; rewrite H1; rewrite H2. + repeat rewrite mkPX_ok; simpl. + rsimpl. + apply radd_ext; rsimpl. + rewrite (ARadd_comm ARth); rsimpl. + apply radd_ext; rsimpl. + rewrite (ARadd_comm ARth); rsimpl. + rewrite zmon_pred_ok;rsimpl. + intros j M1. + case_eq ((i ?= j) Eq); intros He; simpl. + rewrite (Pcompare_Eq_eq _ _ He). + generalize (Hrec1 (c, mkZmon xH M1) l); case (MFactor P2 c (mkZmon xH M1)); + simpl; intros P3 Q3 H; repeat rewrite mkPinj_ok; auto. + rewrite H; rewrite mkPX_ok; rsimpl. + repeat (rewrite <-(ARadd_assoc ARth)). + apply radd_ext; rsimpl. + rewrite (ARadd_comm ARth); rsimpl. + apply radd_ext; rsimpl. + repeat (rewrite <-(ARmul_assoc ARth)). + rewrite mkZmon_ok. + apply rmul_ext; rsimpl. + repeat (rewrite <-(ARmul_assoc ARth)). + apply rmul_ext; rsimpl. + rewrite (ARmul_comm ARth); rsimpl. + generalize (Hrec1 (c, vmon (j - i) M1) l); + case (MFactor P2 c (vmon (j - i) M1)); + simpl; intros P3 Q3 H; repeat rewrite mkPinj_ok; auto. + rewrite H; rsimpl; repeat rewrite mkPinj_ok; auto. + rewrite mkPX_ok; rsimpl. + repeat (rewrite <-(ARadd_assoc ARth)). + apply radd_ext; rsimpl. + rewrite (ARadd_comm ARth); rsimpl. + apply radd_ext; rsimpl. + repeat (rewrite <-(ARmul_assoc ARth)). + apply rmul_ext; rsimpl. + rewrite (ARmul_comm ARth); rsimpl. + apply rmul_ext; rsimpl. + rewrite <- (ARmul_comm ARth (Mphi (tail l) M1)); rsimpl. + repeat (rewrite <-(ARmul_assoc ARth)). + apply rmul_ext; rsimpl. + rewrite <- pow_pos_Pplus. + rewrite (Pplus_minus _ _ (ZC2 _ _ He)); rsimpl. + generalize (Hrec1 (c, mkZmon 1 M1) l); + case (MFactor P2 c (mkZmon 1 M1)); + simpl; intros P3 Q3 H; repeat rewrite mkPinj_ok; auto. + rewrite H; rsimpl. + rewrite mkPX_ok; rsimpl. + repeat (rewrite <-(ARadd_assoc ARth)). + apply radd_ext; rsimpl. + rewrite (ARadd_comm ARth); rsimpl. + apply radd_ext; rsimpl. + rewrite mkZmon_ok. + repeat (rewrite <-(ARmul_assoc ARth)). + apply rmul_ext; rsimpl. + rewrite (ARmul_comm ARth); rsimpl. + rewrite mkPX_ok; simpl; rsimpl. + rewrite (morph0 CRmorph); rsimpl. + repeat (rewrite <-(ARmul_assoc ARth)). + rewrite (ARmul_comm ARth (Q3@l)); rsimpl. + apply rmul_ext; rsimpl. + rewrite (ARmul_comm ARth); rsimpl. + repeat (rewrite <- (ARmul_assoc ARth)). + apply rmul_ext; rsimpl. + rewrite <- pow_pos_Pplus. + rewrite (Pplus_minus _ _ He); rsimpl. + Qed. + +(* Proof for the symmetric version *) + + Lemma POneSubst_ok: forall P1 M1 P2 P3 l, + POneSubst P1 M1 P2 = Some P3 -> phi (fst M1) * Mphi l (snd M1) == P2@l -> P1@l == P3@l. + Proof. + intros P2 (cc,M1) P3 P4 l; unfold POneSubst. + generalize (Mphi_ok P2 (cc, M1) l); case (MFactor P2 cc M1); simpl; auto. + intros Q1 R1; case R1. + intros c H; rewrite H. + generalize (morph_eq CRmorph c cO); + case (c ?=! cO); simpl; auto. + intros H1 H2; rewrite H1; auto; rsimpl. + discriminate. + intros _ H1 H2; injection H1; intros; subst. + rewrite H2; rsimpl. + (* new version *) + rewrite Padd_ok; rewrite PmulC_ok; rsimpl. + intros i P5 H; rewrite H. + intros HH H1; injection HH; intros; subst; rsimpl. + rewrite Padd_ok; rewrite PmulI_ok by (intros;apply Pmul_ok). rewrite H1; rsimpl. + intros i P5 P6 H1 H2 H3; rewrite H1; rewrite H3. + assert (P4 = Q1 ++ P3 ** PX i P5 P6). + injection H2; intros; subst;trivial. + rewrite H;rewrite Padd_ok;rewrite Pmul_ok;rsimpl. + Qed. +(* + Lemma POneSubst_ok: forall P1 M1 P2 P3 l, + POneSubst P1 M1 P2 = Some P3 -> Mphi l M1 == P2@l -> P1@l == P3@l. +Proof. + intros P2 M1 P3 P4 l; unfold POneSubst. + generalize (Mphi_ok P2 M1 l); case (MFactor P2 M1); simpl; auto. + intros Q1 R1; case R1. + intros c H; rewrite H. + generalize (morph_eq CRmorph c cO); + case (c ?=! cO); simpl; auto. + intros H1 H2; rewrite H1; auto; rsimpl. + discriminate. + intros _ H1 H2; injection H1; intros; subst. + rewrite H2; rsimpl. + rewrite Padd_ok; rewrite Pmul_ok; rsimpl. + intros i P5 H; rewrite H. + intros HH H1; injection HH; intros; subst; rsimpl. + rewrite Padd_ok; rewrite Pmul_ok. rewrite H1; rsimpl. + intros i P5 P6 H1 H2 H3; rewrite H1; rewrite H3. + injection H2; intros; subst; rsimpl. + rewrite Padd_ok. + rewrite Pmul_ok; rsimpl. + Qed. +*) + Lemma PNSubst1_ok: forall n P1 M1 P2 l, + [fst M1] * Mphi l (snd M1) == P2@l -> P1@l == (PNSubst1 P1 M1 P2 n)@l. + Proof. + intros n; elim n; simpl; auto. + intros P2 M1 P3 l H. + generalize (fun P4 => @POneSubst_ok P2 M1 P3 P4 l); + case (POneSubst P2 M1 P3); [idtac | intros; rsimpl]. + intros P4 Hrec; rewrite (Hrec P4); auto; rsimpl. + intros n1 Hrec P2 M1 P3 l H. + generalize (fun P4 => @POneSubst_ok P2 M1 P3 P4 l); + case (POneSubst P2 M1 P3); [idtac | intros; rsimpl]. + intros P4 Hrec1; rewrite (Hrec1 P4); auto; rsimpl. + Qed. + + Lemma PNSubst_ok: forall n P1 M1 P2 l P3, + PNSubst P1 M1 P2 n = Some P3 -> [fst M1] * Mphi l (snd M1) == P2@l -> P1@l == P3@l. + Proof. + intros n P2 (cc, M1) P3 l P4; unfold PNSubst. + generalize (fun P4 => @POneSubst_ok P2 (cc,M1) P3 P4 l); + case (POneSubst P2 (cc,M1) P3); [idtac | intros; discriminate]. + intros P5 H1; case n; try (intros; discriminate). + intros n1 H2; injection H2; intros; subst. + rewrite <- PNSubst1_ok; auto. + Qed. + + Fixpoint MPcond (LM1: list (C * Mon * Pol)) (l: list R) {struct LM1} : Prop := + match LM1 with + cons (M1,P2) LM2 => ([fst M1] * Mphi l (snd M1) == P2@l) /\ (MPcond LM2 l) + | _ => True + end. + + Lemma PSubstL1_ok: forall n LM1 P1 l, + MPcond LM1 l -> P1@l == (PSubstL1 P1 LM1 n)@l. + Proof. + intros n LM1; elim LM1; simpl; auto. + intros; rsimpl. + intros (M2,P2) LM2 Hrec P3 l [H H1]. + rewrite <- Hrec; auto. + apply PNSubst1_ok; auto. + Qed. + + Lemma PSubstL_ok: forall n LM1 P1 P2 l, + PSubstL P1 LM1 n = Some P2 -> MPcond LM1 l -> P1@l == P2@l. + Proof. + intros n LM1; elim LM1; simpl; auto. + intros; discriminate. + intros (M2,P2) LM2 Hrec P3 P4 l. + generalize (PNSubst_ok n P3 M2 P2); case (PNSubst P3 M2 P2 n). + intros P5 H0 H1 [H2 H3]; injection H1; intros; subst. + rewrite <- PSubstL1_ok; auto. + intros l1 H [H1 H2]; auto. + Qed. + + Lemma PNSubstL_ok: forall m n LM1 P1 l, + MPcond LM1 l -> P1@l == (PNSubstL P1 LM1 m n)@l. + Proof. + intros m; elim m; simpl; auto. + intros n LM1 P2 l H; generalize (fun P3 => @PSubstL_ok n LM1 P2 P3 l); + case (PSubstL P2 LM1 n); intros; rsimpl; auto. + intros m1 Hrec n LM1 P2 l H. + generalize (fun P3 => @PSubstL_ok n LM1 P2 P3 l); + case (PSubstL P2 LM1 n); intros; rsimpl; auto. + rewrite <- Hrec; auto. + Qed. + + (** Definition of polynomial expressions *) + + Inductive PExpr : Type := + | PEc : C -> PExpr + | PEX : positive -> PExpr + | PEadd : PExpr -> PExpr -> PExpr + | PEsub : PExpr -> PExpr -> PExpr + | PEmul : PExpr -> PExpr -> PExpr + | PEopp : PExpr -> PExpr + | PEpow : PExpr -> N -> PExpr. + + (** evaluation of polynomial expressions towards R *) + Definition mk_X j := mkPinj_pred j mkX. + + (** evaluation of polynomial expressions towards R *) + + Fixpoint PEeval (l:list R) (pe:PExpr) {struct pe} : R := + match pe with + | PEc c => phi c + | PEX j => nth 0 j l + | PEadd pe1 pe2 => (PEeval l pe1) + (PEeval l pe2) + | PEsub pe1 pe2 => (PEeval l pe1) - (PEeval l pe2) + | PEmul pe1 pe2 => (PEeval l pe1) * (PEeval l pe2) + | PEopp pe1 => - (PEeval l pe1) + | PEpow pe1 n => rpow (PEeval l pe1) (Cp_phi n) + end. + +Strategy expand [PEeval]. + + (** Correctness proofs *) + + Lemma mkX_ok : forall p l, nth 0 p l == (mk_X p) @ l. + Proof. + destruct p;simpl;intros;Esimpl;trivial. + rewrite <-jump_tl;rewrite nth_jump;rrefl. + rewrite <- nth_jump. + rewrite nth_Pdouble_minus_one;rrefl. + Qed. + + Ltac Esimpl3 := + repeat match goal with + | |- context [(?P1 ++ ?P2)@?l] => rewrite (Padd_ok P2 P1 l) + | |- context [(?P1 -- ?P2)@?l] => rewrite (Psub_ok P2 P1 l) + end;Esimpl2;try rrefl;try apply (ARadd_comm ARth). + +(* Power using the chinise algorithm *) +(*Section POWER. + Variable subst_l : Pol -> Pol. + Fixpoint Ppow_pos (P:Pol) (p:positive){struct p} : Pol := + match p with + | xH => P + | xO p => subst_l (Psquare (Ppow_pos P p)) + | xI p => subst_l (Pmul P (Psquare (Ppow_pos P p))) + end. + + Definition Ppow_N P n := + match n with + | N0 => P1 + | Npos p => Ppow_pos P p + end. + + Lemma Ppow_pos_ok : forall l, (forall P, subst_l P@l == P@l) -> + forall P p, (Ppow_pos P p)@l == (pow_pos Pmul P p)@l. + Proof. + intros l subst_l_ok P. + induction p;simpl;intros;try rrefl;try rewrite subst_l_ok. + repeat rewrite Pmul_ok;rewrite Psquare_ok;rewrite IHp;rrefl. + repeat rewrite Pmul_ok;rewrite Psquare_ok;rewrite IHp;rrefl. + Qed. + + Lemma Ppow_N_ok : forall l, (forall P, subst_l P@l == P@l) -> + forall P n, (Ppow_N P n)@l == (pow_N P1 Pmul P n)@l. + Proof. destruct n;simpl. rrefl. apply Ppow_pos_ok. trivial. Qed. + + End POWER. *) + +Section POWER. + Variable subst_l : Pol -> Pol. + Fixpoint Ppow_pos (res P:Pol) (p:positive){struct p} : Pol := + match p with + | xH => subst_l (Pmul res P) + | xO p => Ppow_pos (Ppow_pos res P p) P p + | xI p => subst_l (Pmul (Ppow_pos (Ppow_pos res P p) P p) P) + end. + + Definition Ppow_N P n := + match n with + | N0 => P1 + | Npos p => Ppow_pos P1 P p + end. + + Lemma Ppow_pos_ok : forall l, (forall P, subst_l P@l == P@l) -> + forall res P p, (Ppow_pos res P p)@l == res@l * (pow_pos Pmul P p)@l. + Proof. + intros l subst_l_ok res P p. generalize res;clear res. + induction p;simpl;intros;try rewrite subst_l_ok; repeat rewrite Pmul_ok;repeat rewrite IHp. + rsimpl. mul_push (P@l);rsimpl. rsimpl. rrefl. + Qed. + + Lemma Ppow_N_ok : forall l, (forall P, subst_l P@l == P@l) -> + forall P n, (Ppow_N P n)@l == (pow_N P1 Pmul P n)@l. + Proof. destruct n;simpl. rrefl. rewrite Ppow_pos_ok by trivial. Esimpl. Qed. + + End POWER. + + (** Normalization and rewriting *) + + Section NORM_SUBST_REC. + Variable n : nat. + Variable lmp:list (C*Mon*Pol). + Let subst_l P := PNSubstL P lmp n n. + Let Pmul_subst P1 P2 := subst_l (Pmul P1 P2). + Let Ppow_subst := Ppow_N subst_l. + + Fixpoint norm_aux (pe:PExpr) : Pol := + match pe with + | PEc c => Pc c + | PEX j => mk_X j + | PEadd (PEopp pe1) pe2 => Psub (norm_aux pe2) (norm_aux pe1) + | PEadd pe1 (PEopp pe2) => + Psub (norm_aux pe1) (norm_aux pe2) + | PEadd pe1 pe2 => Padd (norm_aux pe1) (norm_aux pe2) + | PEsub pe1 pe2 => Psub (norm_aux pe1) (norm_aux pe2) + | PEmul pe1 pe2 => Pmul (norm_aux pe1) (norm_aux pe2) + | PEopp pe1 => Popp (norm_aux pe1) + | PEpow pe1 n => Ppow_N (fun p => p) (norm_aux pe1) n + end. + + Definition norm_subst pe := subst_l (norm_aux pe). + + (* + Fixpoint norm_subst (pe:PExpr) : Pol := + match pe with + | PEc c => Pc c + | PEX j => subst_l (mk_X j) + | PEadd (PEopp pe1) pe2 => Psub (norm_subst pe2) (norm_subst pe1) + | PEadd pe1 (PEopp pe2) => + Psub (norm_subst pe1) (norm_subst pe2) + | PEadd pe1 pe2 => Padd (norm_subst pe1) (norm_subst pe2) + | PEsub pe1 pe2 => Psub (norm_subst pe1) (norm_subst pe2) + | PEmul pe1 pe2 => Pmul_subst (norm_subst pe1) (norm_subst pe2) + | PEopp pe1 => Popp (norm_subst pe1) + | PEpow pe1 n => Ppow_subst (norm_subst pe1) n + end. + + Lemma norm_subst_spec : + forall l pe, MPcond lmp l -> + PEeval l pe == (norm_subst pe)@l. + Proof. + intros;assert (subst_l_ok:forall P, (subst_l P)@l == P@l). + unfold subst_l;intros. + rewrite <- PNSubstL_ok;trivial. rrefl. + assert (Pms_ok:forall P1 P2, (Pmul_subst P1 P2)@l == P1@l*P2@l). + intros;unfold Pmul_subst;rewrite subst_l_ok;rewrite Pmul_ok;rrefl. + induction pe;simpl;Esimpl3. + rewrite subst_l_ok;apply mkX_ok. + rewrite IHpe1;rewrite IHpe2;destruct pe1;destruct pe2;Esimpl3. + rewrite IHpe1;rewrite IHpe2;rrefl. + rewrite Pms_ok;rewrite IHpe1;rewrite IHpe2;rrefl. + rewrite IHpe;rrefl. + unfold Ppow_subst. rewrite Ppow_N_ok. trivial. + rewrite pow_th.(rpow_pow_N). destruct n0;Esimpl3. + induction p;simpl;try rewrite IHp;try rewrite IHpe;repeat rewrite Pms_ok; + repeat rewrite Pmul_ok;rrefl. + Qed. +*) + Lemma norm_aux_spec : + forall l pe, MPcond lmp l -> + PEeval l pe == (norm_aux pe)@l. + Proof. + intros. + induction pe;simpl;Esimpl3. + apply mkX_ok. + rewrite IHpe1;rewrite IHpe2;destruct pe1;destruct pe2;Esimpl3. + rewrite IHpe1;rewrite IHpe2;rrefl. + rewrite IHpe1;rewrite IHpe2. rewrite Pmul_ok. rrefl. + rewrite IHpe;rrefl. + rewrite Ppow_N_ok by (intros;rrefl). + rewrite pow_th.(rpow_pow_N). destruct n0;Esimpl3. + induction p;simpl;try rewrite IHp;try rewrite IHpe;repeat rewrite Pms_ok; + repeat rewrite Pmul_ok;rrefl. + Qed. + + Lemma norm_subst_spec : + forall l pe, MPcond lmp l -> + PEeval l pe == (norm_subst pe)@l. + Proof. + intros;unfold norm_subst. + unfold subst_l;rewrite <- PNSubstL_ok;trivial. apply norm_aux_spec. trivial. + Qed. + + End NORM_SUBST_REC. + + Fixpoint interp_PElist (l:list R) (lpe:list (PExpr*PExpr)) {struct lpe} : Prop := + match lpe with + | nil => True + | (me,pe)::lpe => + match lpe with + | nil => PEeval l me == PEeval l pe + | _ => PEeval l me == PEeval l pe /\ interp_PElist l lpe + end + end. + + Fixpoint mon_of_pol (P:Pol) : option (C * Mon) := + match P with + | Pc c => if (c ?=! cO) then None else Some (c, mon0) + | Pinj j P => + match mon_of_pol P with + | None => None + | Some (c,m) => Some (c, mkZmon j m) + end + | PX P i Q => + if Peq Q P0 then + match mon_of_pol P with + | None => None + | Some (c,m) => Some (c, mkVmon i m) + end + else None + end. + + Fixpoint mk_monpol_list (lpe:list (PExpr * PExpr)) : list (C*Mon*Pol) := + match lpe with + | nil => nil + | (me,pe)::lpe => + match mon_of_pol (norm_subst 0 nil me) with + | None => mk_monpol_list lpe + | Some m => (m,norm_subst 0 nil pe):: mk_monpol_list lpe + end + end. + + Lemma mon_of_pol_ok : forall P m, mon_of_pol P = Some m -> + forall l, [fst m] * Mphi l (snd m) == P@l. + Proof. + induction P;simpl;intros;Esimpl. + assert (H1 := (morph_eq CRmorph) c cO). + destruct (c ?=! cO). + discriminate. + inversion H;trivial;Esimpl. + generalize H;clear H;case_eq (mon_of_pol P). + intros (c1,P2) H0 H1; inversion H1; Esimpl. + generalize (IHP (c1, P2) H0 (jump p l)). + rewrite mkZmon_ok;simpl;auto. + intros; discriminate. + generalize H;clear H;change match P3 with + | Pc c => c ?=! cO + | Pinj _ _ => false + | PX _ _ _ => false + end with (P3 ?== P0). + assert (H := Peq_ok P3 P0). + destruct (P3 ?== P0). + case_eq (mon_of_pol P2);try intros (cc, pp); intros. + inversion H1. + simpl. + rewrite mkVmon_ok;simpl. + rewrite H;trivial;Esimpl. + generalize (IHP1 _ H0); simpl; intros HH; rewrite HH; rsimpl. + discriminate. + intros;discriminate. + Qed. + + Lemma interp_PElist_ok : forall l lpe, + interp_PElist l lpe -> MPcond (mk_monpol_list lpe) l. + Proof. + induction lpe;simpl. trivial. + destruct a;simpl;intros. + assert (HH:=mon_of_pol_ok (norm_subst 0 nil p)); + destruct (mon_of_pol (norm_subst 0 nil p)). + split. + rewrite <- norm_subst_spec by exact I. + destruct lpe;try destruct H;rewrite <- H; + rewrite (norm_subst_spec 0 nil); try exact I;apply HH;trivial. + apply IHlpe. destruct lpe;simpl;trivial. destruct H. exact H0. + apply IHlpe. destruct lpe;simpl;trivial. destruct H. exact H0. + Qed. + + Lemma norm_subst_ok : forall n l lpe pe, + interp_PElist l lpe -> + PEeval l pe == (norm_subst n (mk_monpol_list lpe) pe)@l. + Proof. + intros;apply norm_subst_spec. apply interp_PElist_ok;trivial. + Qed. + + Lemma ring_correct : forall n l lpe pe1 pe2, + interp_PElist l lpe -> + (let lmp := mk_monpol_list lpe in + norm_subst n lmp pe1 ?== norm_subst n lmp pe2) = true -> + PEeval l pe1 == PEeval l pe2. + Proof. + simpl;intros. + do 2 (rewrite (norm_subst_ok n l lpe);trivial). + apply Peq_ok;trivial. + Qed. + + + + (** Generic evaluation of polynomial towards R avoiding parenthesis *) + Variable get_sign : C -> option C. + Variable get_sign_spec : sign_theory copp ceqb get_sign. + + + Section EVALUATION. + + (* [mkpow x p] = x^p *) + Variable mkpow : R -> positive -> R. + (* [mkpow x p] = -(x^p) *) + Variable mkopp_pow : R -> positive -> R. + (* [mkmult_pow r x p] = r * x^p *) + Variable mkmult_pow : R -> R -> positive -> R. + + Fixpoint mkmult_rec (r:R) (lm:list (R*positive)) {struct lm}: R := + match lm with + | nil => r + | cons (x,p) t => mkmult_rec (mkmult_pow r x p) t + end. + + Definition mkmult1 lm := + match lm with + | nil => 1 + | cons (x,p) t => mkmult_rec (mkpow x p) t + end. + + Definition mkmultm1 lm := + match lm with + | nil => ropp rI + | cons (x,p) t => mkmult_rec (mkopp_pow x p) t + end. + + Definition mkmult_c_pos c lm := + if c ?=! cI then mkmult1 (rev' lm) + else mkmult_rec [c] (rev' lm). + + Definition mkmult_c c lm := + match get_sign c with + | None => mkmult_c_pos c lm + | Some c' => + if c' ?=! cI then mkmultm1 (rev' lm) + else mkmult_rec [c] (rev' lm) + end. + + Definition mkadd_mult rP c lm := + match get_sign c with + | None => rP + mkmult_c_pos c lm + | Some c' => rP - mkmult_c_pos c' lm + end. + + Definition add_pow_list (r:R) n l := + match n with + | N0 => l + | Npos p => (r,p)::l + end. + + Fixpoint add_mult_dev + (rP:R) (P:Pol) (fv:list R) (n:N) (lm:list (R*positive)) {struct P} : R := + match P with + | Pc c => + let lm := add_pow_list (hd 0 fv) n lm in + mkadd_mult rP c lm + | Pinj j Q => + add_mult_dev rP Q (jump j fv) N0 (add_pow_list (hd 0 fv) n lm) + | PX P i Q => + let rP := add_mult_dev rP P fv (Nplus (Npos i) n) lm in + if Q ?== P0 then rP + else add_mult_dev rP Q (tail fv) N0 (add_pow_list (hd 0 fv) n lm) + end. + + Fixpoint mult_dev (P:Pol) (fv : list R) (n:N) + (lm:list (R*positive)) {struct P} : R := + (* P@l * (hd 0 l)^n * lm *) + match P with + | Pc c => mkmult_c c (add_pow_list (hd 0 fv) n lm) + | Pinj j Q => mult_dev Q (jump j fv) N0 (add_pow_list (hd 0 fv) n lm) + | PX P i Q => + let rP := mult_dev P fv (Nplus (Npos i) n) lm in + if Q ?== P0 then rP + else + let lmq := add_pow_list (hd 0 fv) n lm in + add_mult_dev rP Q (tail fv) N0 lmq + end. + + Definition Pphi_avoid fv P := mult_dev P fv N0 nil. + + Fixpoint r_list_pow (l:list (R*positive)) : R := + match l with + | nil => rI + | cons (r,p) l => pow_pos rmul r p * r_list_pow l + end. + + Hypothesis mkpow_spec : forall r p, mkpow r p == pow_pos rmul r p. + Hypothesis mkopp_pow_spec : forall r p, mkopp_pow r p == - (pow_pos rmul r p). + Hypothesis mkmult_pow_spec : forall r x p, mkmult_pow r x p == r * pow_pos rmul x p. + + Lemma mkmult_rec_ok : forall lm r, mkmult_rec r lm == r * r_list_pow lm. + Proof. + induction lm;intros;simpl;Esimpl. + destruct a as (x,p);Esimpl. + rewrite IHlm. rewrite mkmult_pow_spec. Esimpl. + Qed. + + Lemma mkmult1_ok : forall lm, mkmult1 lm == r_list_pow lm. + Proof. + destruct lm;simpl;Esimpl. + destruct p. rewrite mkmult_rec_ok;rewrite mkpow_spec;Esimpl. + Qed. + + Lemma mkmultm1_ok : forall lm, mkmultm1 lm == - r_list_pow lm. + Proof. + destruct lm;simpl;Esimpl. + destruct p;rewrite mkmult_rec_ok. rewrite mkopp_pow_spec;Esimpl. + Qed. + + Lemma r_list_pow_rev : forall l, r_list_pow (rev' l) == r_list_pow l. + Proof. + assert + (forall l lr : list (R * positive), r_list_pow (rev_append l lr) == r_list_pow lr * r_list_pow l). + induction l;intros;simpl;Esimpl. + destruct a;rewrite IHl;Esimpl. + rewrite (ARmul_comm ARth (pow_pos rmul r p)). rrefl. + intros;unfold rev'. rewrite H;simpl;Esimpl. + Qed. + + Lemma mkmult_c_pos_ok : forall c lm, mkmult_c_pos c lm == [c]* r_list_pow lm. + Proof. + intros;unfold mkmult_c_pos;simpl. + assert (H := (morph_eq CRmorph) c cI). + rewrite <- r_list_pow_rev; destruct (c ?=! cI). + rewrite H;trivial;Esimpl. + apply mkmult1_ok. apply mkmult_rec_ok. + Qed. + + Lemma mkmult_c_ok : forall c lm, mkmult_c c lm == [c] * r_list_pow lm. + Proof. + intros;unfold mkmult_c;simpl. + case_eq (get_sign c);intros. + assert (H1 := (morph_eq CRmorph) c0 cI). + destruct (c0 ?=! cI). + rewrite (CRmorph.(morph_eq) _ _ (get_sign_spec.(sign_spec) _ H)). Esimpl. rewrite H1;trivial. + rewrite <- r_list_pow_rev;trivial;Esimpl. + apply mkmultm1_ok. + rewrite <- r_list_pow_rev; apply mkmult_rec_ok. + apply mkmult_c_pos_ok. +Qed. + + Lemma mkadd_mult_ok : forall rP c lm, mkadd_mult rP c lm == rP + [c]*r_list_pow lm. + Proof. + intros;unfold mkadd_mult. + case_eq (get_sign c);intros. + rewrite (CRmorph.(morph_eq) _ _ (get_sign_spec.(sign_spec) _ H));Esimpl. + rewrite mkmult_c_pos_ok;Esimpl. + rewrite mkmult_c_pos_ok;Esimpl. + Qed. + + Lemma add_pow_list_ok : + forall r n l, r_list_pow (add_pow_list r n l) == pow_N rI rmul r n * r_list_pow l. + Proof. + destruct n;simpl;intros;Esimpl. + Qed. + + Lemma add_mult_dev_ok : forall P rP fv n lm, + add_mult_dev rP P fv n lm == rP + P@fv*pow_N rI rmul (hd 0 fv) n * r_list_pow lm. + Proof. + induction P;simpl;intros. + rewrite mkadd_mult_ok. rewrite add_pow_list_ok; Esimpl. + rewrite IHP. simpl. rewrite add_pow_list_ok; Esimpl. + change (match P3 with + | Pc c => c ?=! cO + | Pinj _ _ => false + | PX _ _ _ => false + end) with (Peq P3 P0). + change match n with + | N0 => Npos p + | Npos q => Npos (p + q) + end with (Nplus (Npos p) n);trivial. + assert (H := Peq_ok P3 P0). + destruct (P3 ?== P0). + rewrite (H (refl_equal true)). + rewrite IHP1. destruct n;simpl;Esimpl;rewrite pow_pos_Pplus;Esimpl. + rewrite IHP2. + rewrite IHP1. destruct n;simpl;Esimpl;rewrite pow_pos_Pplus;Esimpl. + Qed. + + Lemma mult_dev_ok : forall P fv n lm, + mult_dev P fv n lm == P@fv * pow_N rI rmul (hd 0 fv) n * r_list_pow lm. + Proof. + induction P;simpl;intros;Esimpl. + rewrite mkmult_c_ok;rewrite add_pow_list_ok;Esimpl. + rewrite IHP. simpl;rewrite add_pow_list_ok;Esimpl. + change (match P3 with + | Pc c => c ?=! cO + | Pinj _ _ => false + | PX _ _ _ => false + end) with (Peq P3 P0). + change match n with + | N0 => Npos p + | Npos q => Npos (p + q) + end with (Nplus (Npos p) n);trivial. + assert (H := Peq_ok P3 P0). + destruct (P3 ?== P0). + rewrite (H (refl_equal true)). + rewrite IHP1. destruct n;simpl;Esimpl;rewrite pow_pos_Pplus;Esimpl. + rewrite add_mult_dev_ok. rewrite IHP1; rewrite add_pow_list_ok. + destruct n;simpl;Esimpl;rewrite pow_pos_Pplus;Esimpl. + Qed. + + Lemma Pphi_avoid_ok : forall P fv, Pphi_avoid fv P == P@fv. + Proof. + unfold Pphi_avoid;intros;rewrite mult_dev_ok;simpl;Esimpl. + Qed. + + End EVALUATION. + + Definition Pphi_pow := + let mkpow x p := + match p with xH => x | _ => rpow x (Cp_phi (Npos p)) end in + let mkopp_pow x p := ropp (mkpow x p) in + let mkmult_pow r x p := rmul r (mkpow x p) in + Pphi_avoid mkpow mkopp_pow mkmult_pow. + + Lemma local_mkpow_ok : + forall (r : R) (p : positive), + match p with + | xI _ => rpow r (Cp_phi (Npos p)) + | xO _ => rpow r (Cp_phi (Npos p)) + | 1 => r + end == pow_pos rmul r p. + Proof. intros r p;destruct p;try rewrite pow_th.(rpow_pow_N);reflexivity. Qed. + + Lemma Pphi_pow_ok : forall P fv, Pphi_pow fv P == P@fv. + Proof. + unfold Pphi_pow;intros;apply Pphi_avoid_ok;intros;try rewrite local_mkpow_ok;rrefl. + Qed. + + Lemma ring_rw_pow_correct : forall n lH l, + interp_PElist l lH -> + forall lmp, mk_monpol_list lH = lmp -> + forall pe npe, norm_subst n lmp pe = npe -> + PEeval l pe == Pphi_pow l npe. + Proof. + intros n lH l H1 lmp Heq1 pe npe Heq2. + rewrite Pphi_pow_ok. rewrite <- Heq2;rewrite <- Heq1. + apply norm_subst_ok. trivial. + Qed. + + Fixpoint mkmult_pow (r x:R) (p: positive) {struct p} : R := + match p with + | xH => r*x + | xO p => mkmult_pow (mkmult_pow r x p) x p + | xI p => mkmult_pow (mkmult_pow (r*x) x p) x p + end. + + Definition mkpow x p := + match p with + | xH => x + | xO p => mkmult_pow x x (Pdouble_minus_one p) + | xI p => mkmult_pow x x (xO p) + end. + + Definition mkopp_pow x p := + match p with + | xH => -x + | xO p => mkmult_pow (-x) x (Pdouble_minus_one p) + | xI p => mkmult_pow (-x) x (xO p) + end. + + Definition Pphi_dev := Pphi_avoid mkpow mkopp_pow mkmult_pow. + + Lemma mkmult_pow_ok : forall p r x, mkmult_pow r x p == r*pow_pos rmul x p. + Proof. + induction p;intros;simpl;Esimpl. + repeat rewrite IHp;Esimpl. + repeat rewrite IHp;Esimpl. + Qed. + + Lemma mkpow_ok : forall p x, mkpow x p == pow_pos rmul x p. + Proof. + destruct p;simpl;intros;Esimpl. + repeat rewrite mkmult_pow_ok;Esimpl. + rewrite mkmult_pow_ok;Esimpl. + pattern x at 1;replace x with (pow_pos rmul x 1). + rewrite <- pow_pos_Pplus. + rewrite <- Pplus_one_succ_l. + rewrite Psucc_o_double_minus_one_eq_xO. + simpl;Esimpl. + trivial. + Qed. + + Lemma mkopp_pow_ok : forall p x, mkopp_pow x p == - pow_pos rmul x p. + Proof. + destruct p;simpl;intros;Esimpl. + repeat rewrite mkmult_pow_ok;Esimpl. + rewrite mkmult_pow_ok;Esimpl. + pattern x at 1;replace x with (pow_pos rmul x 1). + rewrite <- pow_pos_Pplus. + rewrite <- Pplus_one_succ_l. + rewrite Psucc_o_double_minus_one_eq_xO. + simpl;Esimpl. + trivial. + Qed. + + Lemma Pphi_dev_ok : forall P fv, Pphi_dev fv P == P@fv. + Proof. + unfold Pphi_dev;intros;apply Pphi_avoid_ok. + intros;apply mkpow_ok. + intros;apply mkopp_pow_ok. + intros;apply mkmult_pow_ok. + Qed. + + Lemma ring_rw_correct : forall n lH l, + interp_PElist l lH -> + forall lmp, mk_monpol_list lH = lmp -> + forall pe npe, norm_subst n lmp pe = npe -> + PEeval l pe == Pphi_dev l npe. + Proof. + intros n lH l H1 lmp Heq1 pe npe Heq2. + rewrite Pphi_dev_ok. rewrite <- Heq2;rewrite <- Heq1. + apply norm_subst_ok. trivial. + Qed. + + +End MakeRingPol. + diff --git a/plugins/setoid_ring/Ring_tac.v b/plugins/setoid_ring/Ring_tac.v new file mode 100644 index 00000000..d33e9a82 --- /dev/null +++ b/plugins/setoid_ring/Ring_tac.v @@ -0,0 +1,434 @@ +Set Implicit Arguments. +Require Import Setoid. +Require Import BinPos. +Require Import Ring_polynom. +Require Import BinList. +Require Import InitialRing. +Require Import Quote. +Declare ML Module "newring_plugin". + + +(* adds a definition t' on the normal form of t and an hypothesis id + stating that t = t' (tries to produces a proof as small as possible) *) +Ltac compute_assertion eqn t' t := + let nft := eval vm_compute in t in + pose (t' := nft); + assert (eqn : t = t'); + [vm_cast_no_check (refl_equal t')|idtac]. + +Ltac relation_carrier req := + let ty := type of req in + match eval hnf in ty with + ?R -> _ => R + | _ => fail 1000 "Equality has no relation type" + end. + +Ltac Get_goal := match goal with [|- ?G] => G end. + +(********************************************************************) +(* Tacticals to build reflexive tactics *) + +Ltac OnEquation req := + match goal with + | |- req ?lhs ?rhs => (fun f => f lhs rhs) + | _ => (fun _ => fail "Goal is not an equation (of expected equality)") + end. + +Ltac OnEquationHyp req h := + match type of h with + | req ?lhs ?rhs => fun f => f lhs rhs + | _ => (fun _ => fail "Hypothesis is not an equation (of expected equality)") + end. + +(* Note: auxiliary subgoals in reverse order *) +Ltac OnMainSubgoal H ty := + match ty with + | _ -> ?ty' => + let subtac := OnMainSubgoal H ty' in + fun kont => lapply H; [clear H; intro H; subtac kont | idtac] + | _ => (fun kont => kont()) + end. + +(* A generic pattern to have reflexive tactics do some computation: + lemmas of the form [forall x', x=x' -> P(x')] are understood as: + compute the normal form of x, instantiate x' with it, prove + hypothesis x=x' with vm_compute and reflexivity, and pass the + instantiated lemma to the continuation. + *) +Ltac ProveLemmaHyp lemma := + match type of lemma with + forall x', ?x = x' -> _ => + (fun kont => + let x' := fresh "res" in + let H := fresh "res_eq" in + compute_assertion H x' x; + let lemma' := constr:(lemma x' H) in + kont lemma'; + (clear H||idtac"ProveLemmaHyp: cleanup failed"); + subst x') + | _ => (fun _ => fail "ProveLemmaHyp: lemma not of the expected form") + end. + +Ltac ProveLemmaHyps lemma := + match type of lemma with + forall x', ?x = x' -> _ => + (fun kont => + let x' := fresh "res" in + let H := fresh "res_eq" in + compute_assertion H x' x; + let lemma' := constr:(lemma x' H) in + ProveLemmaHyps lemma' kont; + (clear H||idtac"ProveLemmaHyps: cleanup failed"); + subst x') + | _ => (fun kont => kont lemma) + end. + +(* +Ltac ProveLemmaHyps lemma := (* expects a continuation *) + let try_step := ProveLemmaHyp lemma in + (fun kont => + try_step ltac:(fun lemma' => ProveLemmaHyps lemma' kont) || + kont lemma). +*) +Ltac ApplyLemmaThen lemma expr kont := + let lem := constr:(lemma expr) in + ProveLemmaHyp lem ltac:(fun lem' => + let Heq := fresh "thm" in + assert (Heq:=lem'); + OnMainSubgoal Heq ltac:(type of Heq) ltac:(fun _ => kont Heq); + (clear Heq||idtac"ApplyLemmaThen: cleanup failed")). +(* +Ltac ApplyLemmaThenAndCont lemma expr tac CONT_tac cont_arg := + let pe := + match type of (lemma expr) with + forall pe', ?pe = pe' -> _ => pe + | _ => fail 1 "ApplyLemmaThenAndCont: cannot find norm expression" + end in + let pe' := fresh "expr_nf" in + let nf_pe := fresh "pe_eq" in + compute_assertion nf_pe pe' pe; + let Heq := fresh "thm" in + (assert (Heq:=lemma pe pe' H) || fail "anomaly: failed to apply lemma"); + clear nf_pe; + OnMainSubgoal Heq ltac:(type of Heq) + ltac:(try tac Heq; clear Heq pe';CONT_tac cont_arg)). +*) +Ltac ApplyLemmaThenAndCont lemma expr tac CONT_tac := + ApplyLemmaThen lemma expr + ltac:(fun lemma' => try tac lemma'; CONT_tac()). + +(* General scheme of reflexive tactics using of correctness lemma + that involves normalisation of one expression + - [FV_tac term fv] is a tactic that adds the atomic expressions + of [term] into [fv] + - [SYN_tac term fv] reifies [term] given the list of atomic expressions + - [LEMMA_tac fv kont] computes the correctness lemma and passes it to + continuation kont + - [MAIN_tac H] process H which is the conclusion of the correctness lemma + instantiated with each reified term + - [fv] is the initial value of atomic expressions (to be completed by + the reification of the terms + - [terms] the list (a constr of type list) of terms to reify and process. + *) +Ltac ReflexiveRewriteTactic + FV_tac SYN_tac LEMMA_tac MAIN_tac fv terms := + (* extend the atom list *) + let fv := list_fold_left FV_tac fv terms in + let RW_tac lemma := + let fcons term CONT_tac := + let expr := SYN_tac term fv in + let main H := + match type of H with + | (?req _ ?rhs) => change (req term rhs) in H + end; + MAIN_tac H in + (ApplyLemmaThenAndCont lemma expr main CONT_tac) in + (* rewrite steps *) + lazy_list_fold_right fcons ltac:(fun _=>idtac) terms in + LEMMA_tac fv RW_tac. + +(********************************************************) + +Ltac FV_hypo_tac mkFV req lH := + let R := relation_carrier req in + let FV_hypo_l_tac h := + match h with @mkhypo (req ?pe _) _ => mkFV pe end in + let FV_hypo_r_tac h := + match h with @mkhypo (req _ ?pe) _ => mkFV pe end in + let fv := list_fold_right FV_hypo_l_tac (@nil R) lH in + list_fold_right FV_hypo_r_tac fv lH. + +Ltac mkHyp_tac C req Reify lH := + let mkHyp h res := + match h with + | @mkhypo (req ?r1 ?r2) _ => + let pe1 := Reify r1 in + let pe2 := Reify r2 in + constr:(cons (pe1,pe2) res) + | _ => fail 1 "hypothesis is not a ring equality" + end in + list_fold_right mkHyp (@nil (PExpr C * PExpr C)) lH. + +Ltac proofHyp_tac lH := + let get_proof h := + match h with + | @mkhypo _ ?p => p + end in + let rec bh l := + match l with + | nil => constr:(I) + | cons ?h nil => get_proof h + | cons ?h ?tl => + let l := get_proof h in + let r := bh tl in + constr:(conj l r) + end in + bh lH. + +Ltac get_MonPol lemma := + match type of lemma with + | context [(mk_monpol_list ?cO ?cI ?cadd ?cmul ?csub ?copp ?cdiv ?ceqb _)] => + constr:(mk_monpol_list cO cI cadd cmul csub copp cdiv ceqb) + | _ => fail 1 "ring/field anomaly: bad correctness lemma (get_MonPol)" + end. + +(********************************************************) + +(* Building the atom list of a ring expression *) +Ltac FV Cst CstPow add mul sub opp pow t fv := + let rec TFV t fv := + let f := + match Cst t with + | NotConstant => + match t with + | (add ?t1 ?t2) => fun _ => TFV t2 ltac:(TFV t1 fv) + | (mul ?t1 ?t2) => fun _ => TFV t2 ltac:(TFV t1 fv) + | (sub ?t1 ?t2) => fun _ => TFV t2 ltac:(TFV t1 fv) + | (opp ?t1) => fun _ => TFV t1 fv + | (pow ?t1 ?n) => + match CstPow n with + | InitialRing.NotConstant => fun _ => AddFvTail t fv + | _ => fun _ => TFV t1 fv + end + | _ => fun _ => AddFvTail t fv + end + | _ => fun _ => fv + end in + f() + in TFV t fv. + + (* syntaxification of ring expressions *) +Ltac mkPolexpr C Cst CstPow radd rmul rsub ropp rpow t fv := + let rec mkP t := + let f := + match Cst t with + | InitialRing.NotConstant => + match t with + | (radd ?t1 ?t2) => + fun _ => + let e1 := mkP t1 in + let e2 := mkP t2 in constr:(PEadd e1 e2) + | (rmul ?t1 ?t2) => + fun _ => + let e1 := mkP t1 in + let e2 := mkP t2 in constr:(PEmul e1 e2) + | (rsub ?t1 ?t2) => + fun _ => + let e1 := mkP t1 in + let e2 := mkP t2 in constr:(PEsub e1 e2) + | (ropp ?t1) => + fun _ => + let e1 := mkP t1 in constr:(PEopp e1) + | (rpow ?t1 ?n) => + match CstPow n with + | InitialRing.NotConstant => + fun _ => let p := Find_at t fv in constr:(PEX C p) + | ?c => fun _ => let e1 := mkP t1 in constr:(PEpow e1 c) + end + | _ => + fun _ => let p := Find_at t fv in constr:(PEX C p) + end + | ?c => fun _ => constr:(@PEc C c) + end in + f () + in mkP t. + +(* packaging the ring structure *) + +Ltac PackRing F req sth ext morph arth cst_tac pow_tac lemma1 lemma2 pre post := + let RNG := + match type of lemma1 with + | context + [@PEeval ?R ?rO ?add ?mul ?sub ?opp ?C ?phi ?Cpow ?powphi ?pow _ _] => + (fun proj => proj + cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2) + | _ => fail 1 "field anomaly: bad correctness lemma (parse)" + end in + F RNG. + +Ltac get_Carrier RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + R). + +Ltac get_Eq RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + req). + +Ltac get_Pre RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + pre). + +Ltac get_Post RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + post). + +Ltac get_NormLemma RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + lemma1). + +Ltac get_SimplifyLemma RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + lemma2). + +Ltac get_RingFV RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + FV cst_tac pow_tac add mul sub opp pow). + +Ltac get_RingMeta RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + mkPolexpr C cst_tac pow_tac add mul sub opp pow). + +Ltac get_RingHypTac RNG := + RNG ltac:(fun cst_tac pow_tac pre post + R req add mul sub opp C Cpow powphi pow lemma1 lemma2 => + let mkPol := mkPolexpr C cst_tac pow_tac add mul sub opp pow in + fun fv lH => mkHyp_tac C req ltac:(fun t => mkPol t fv) lH). + +(* ring tactics *) + +Definition ring_subst_niter := (10*10*10)%nat. + +Ltac Ring RNG lemma lH := + let req := get_Eq RNG in + OnEquation req ltac:(fun lhs rhs => + let mkFV := get_RingFV RNG in + let mkPol := get_RingMeta RNG in + let mkHyp := get_RingHypTac RNG in + let fv := FV_hypo_tac mkFV ltac:(get_Eq RNG) lH in + let fv := mkFV lhs fv in + let fv := mkFV rhs fv in + check_fv fv; + let pe1 := mkPol lhs fv in + let pe2 := mkPol rhs fv in + let lpe := mkHyp fv lH in + let vlpe := fresh "hyp_list" in + let vfv := fresh "fv_list" in + pose (vlpe := lpe); + pose (vfv := fv); + (apply (lemma vfv vlpe pe1 pe2) + || fail "typing error while applying ring"); + [ ((let prh := proofHyp_tac lH in exact prh) + || idtac "can not automatically proof hypothesis :"; + idtac " maybe a left member of a hypothesis is not a monomial") + | vm_compute; + (exact (refl_equal true) || fail "not a valid ring equation")]). + +Ltac Ring_norm_gen f RNG lemma lH rl := + let mkFV := get_RingFV RNG in + let mkPol := get_RingMeta RNG in + let mkHyp := get_RingHypTac RNG in + let mk_monpol := get_MonPol lemma in + let fv := FV_hypo_tac mkFV ltac:(get_Eq RNG) lH in + let lemma_tac fv kont := + let lpe := mkHyp fv lH in + let vlpe := fresh "list_hyp" in + let vlmp := fresh "list_hyp_norm" in + let vlmp_eq := fresh "list_hyp_norm_eq" in + let prh := proofHyp_tac lH in + pose (vlpe := lpe); + compute_assertion vlmp_eq vlmp (mk_monpol vlpe); + let H := fresh "ring_lemma" in + (assert (H := lemma vlpe fv prh vlmp vlmp_eq) + || fail "type error when build the rewriting lemma"); + clear vlmp_eq; + kont H; + (clear H||idtac"Ring_norm_gen: cleanup failed"); + subst vlpe vlmp in + let simpl_ring H := (protect_fv "ring" in H; f H) in + ReflexiveRewriteTactic mkFV mkPol lemma_tac simpl_ring fv rl. + +Ltac Ring_gen RNG lH rl := + let lemma := get_NormLemma RNG in + get_Pre RNG (); + Ring RNG (lemma ring_subst_niter) lH. + +Tactic Notation (at level 0) "ring" := + let G := Get_goal in + ring_lookup (PackRing Ring_gen) [] G. + +Tactic Notation (at level 0) "ring" "[" constr_list(lH) "]" := + let G := Get_goal in + ring_lookup (PackRing Ring_gen) [lH] G. + +(* Simplification *) + +Ltac Ring_simplify_gen f RNG lH rl := + let lemma := get_SimplifyLemma RNG in + let l := fresh "to_rewrite" in + pose (l:= rl); + generalize (refl_equal l); + unfold l at 2; + get_Pre RNG (); + let rl := + match goal with + | [|- l = ?RL -> _ ] => RL + | _ => fail 1 "ring_simplify anomaly: bad goal after pre" + end in + let Heq := fresh "Heq" in + intros Heq;clear Heq l; + Ring_norm_gen f RNG (lemma ring_subst_niter) lH rl; + get_Post RNG (). + +Ltac Ring_simplify := Ring_simplify_gen ltac:(fun H => rewrite H). + +Tactic Notation (at level 0) "ring_simplify" constr_list(rl) := + let G := Get_goal in + ring_lookup (PackRing Ring_simplify) [] rl G. + +Tactic Notation (at level 0) + "ring_simplify" "[" constr_list(lH) "]" constr_list(rl) := + let G := Get_goal in + ring_lookup (PackRing Ring_simplify) [lH] rl G. + +(* MON DIEU QUE C'EST MOCHE !!!!!!!!!!!!! *) + +Tactic Notation "ring_simplify" constr_list(rl) "in" hyp(H):= + let G := Get_goal in + let t := type of H in + let g := fresh "goal" in + set (g:= G); + generalize H;clear H; + ring_lookup (PackRing Ring_simplify) [] rl t; + intro H; + unfold g;clear g. + +Tactic Notation + "ring_simplify" "["constr_list(lH)"]" constr_list(rl) "in" hyp(H):= + let G := Get_goal in + let t := type of H in + let g := fresh "goal" in + set (g:= G); + generalize H;clear H; + ring_lookup (PackRing Ring_simplify) [lH] rl t; + intro H; + unfold g;clear g. + diff --git a/plugins/setoid_ring/Ring_theory.v b/plugins/setoid_ring/Ring_theory.v new file mode 100644 index 00000000..b3250a51 --- /dev/null +++ b/plugins/setoid_ring/Ring_theory.v @@ -0,0 +1,608 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* R -> R. + Variable req : R -> R -> Prop. + Variable Rsth : Setoid_Theory R req. + Notation "x * y " := (rmul x y). + Notation "x == y" := (req x y). + + Hypothesis mul_ext : + forall x1 x2, x1 == x2 -> forall y1 y2, y1 == y2 -> x1 * y1 == x2 * y2. + Hypothesis mul_comm : forall x y, x * y == y * x. + Hypothesis mul_assoc : forall x y z, x * (y * z) == (x * y) * z. + Add Setoid R req Rsth as R_set_Power. + Add Morphism rmul : rmul_ext_Power. exact mul_ext. Qed. + + + Fixpoint pow_pos (x:R) (i:positive) {struct i}: R := + match i with + | xH => x + | xO i => let p := pow_pos x i in rmul p p + | xI i => let p := pow_pos x i in rmul x (rmul p p) + end. + + Lemma pow_pos_Psucc : forall x j, pow_pos x (Psucc j) == x * pow_pos x j. + Proof. + induction j;simpl. + rewrite IHj. + rewrite (mul_comm x (pow_pos x j *pow_pos x j)). + setoid_rewrite (mul_comm x (pow_pos x j)) at 2. + repeat rewrite mul_assoc. apply (Seq_refl _ _ Rsth). + repeat rewrite mul_assoc. apply (Seq_refl _ _ Rsth). + apply (Seq_refl _ _ Rsth). + Qed. + + Lemma pow_pos_Pplus : forall x i j, pow_pos x (i + j) == pow_pos x i * pow_pos x j. + Proof. + intro x;induction i;intros. + rewrite xI_succ_xO;rewrite Pplus_one_succ_r. + rewrite <- Pplus_diag;repeat rewrite <- Pplus_assoc. + repeat rewrite IHi. + rewrite Pplus_comm;rewrite <- Pplus_one_succ_r;rewrite pow_pos_Psucc. + simpl;repeat rewrite mul_assoc. apply (Seq_refl _ _ Rsth). + rewrite <- Pplus_diag;repeat rewrite <- Pplus_assoc. + repeat rewrite IHi;rewrite mul_assoc. apply (Seq_refl _ _ Rsth). + rewrite Pplus_comm;rewrite <- Pplus_one_succ_r;rewrite pow_pos_Psucc; + simpl. apply (Seq_refl _ _ Rsth). + Qed. + + Definition pow_N (x:R) (p:N) := + match p with + | N0 => rI + | Npos p => pow_pos x p + end. + + Definition id_phi_N (x:N) : N := x. + + Lemma pow_N_pow_N : forall x n, pow_N x (id_phi_N n) == pow_N x n. + Proof. + intros; apply (Seq_refl _ _ Rsth). + Qed. + +End Power. + +Section DEFINITIONS. + Variable R : Type. + Variable (rO rI : R) (radd rmul rsub: R->R->R) (ropp : R -> R). + Variable req : R -> R -> Prop. + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Notation "x - y " := (rsub x y). Notation "- x" := (ropp x). + Notation "x == y" := (req x y). + + (** Semi Ring *) + Record semi_ring_theory : Prop := mk_srt { + SRadd_0_l : forall n, 0 + n == n; + SRadd_comm : forall n m, n + m == m + n ; + SRadd_assoc : forall n m p, n + (m + p) == (n + m) + p; + SRmul_1_l : forall n, 1*n == n; + SRmul_0_l : forall n, 0*n == 0; + SRmul_comm : forall n m, n*m == m*n; + SRmul_assoc : forall n m p, n*(m*p) == (n*m)*p; + SRdistr_l : forall n m p, (n + m)*p == n*p + m*p + }. + + (** Almost Ring *) +(*Almost ring are no ring : Ropp_def is missing **) + Record almost_ring_theory : Prop := mk_art { + ARadd_0_l : forall x, 0 + x == x; + ARadd_comm : forall x y, x + y == y + x; + ARadd_assoc : forall x y z, x + (y + z) == (x + y) + z; + ARmul_1_l : forall x, 1 * x == x; + ARmul_0_l : forall x, 0 * x == 0; + ARmul_comm : forall x y, x * y == y * x; + ARmul_assoc : forall x y z, x * (y * z) == (x * y) * z; + ARdistr_l : forall x y z, (x + y) * z == (x * z) + (y * z); + ARopp_mul_l : forall x y, -(x * y) == -x * y; + ARopp_add : forall x y, -(x + y) == -x + -y; + ARsub_def : forall x y, x - y == x + -y + }. + + (** Ring *) + Record ring_theory : Prop := mk_rt { + Radd_0_l : forall x, 0 + x == x; + Radd_comm : forall x y, x + y == y + x; + Radd_assoc : forall x y z, x + (y + z) == (x + y) + z; + Rmul_1_l : forall x, 1 * x == x; + Rmul_comm : forall x y, x * y == y * x; + Rmul_assoc : forall x y z, x * (y * z) == (x * y) * z; + Rdistr_l : forall x y z, (x + y) * z == (x * z) + (y * z); + Rsub_def : forall x y, x - y == x + -y; + Ropp_def : forall x, x + (- x) == 0 + }. + + (** Equality is extensional *) + + Record sring_eq_ext : Prop := mk_seqe { + (* SRing operators are compatible with equality *) + SRadd_ext : + forall x1 x2, x1 == x2 -> forall y1 y2, y1 == y2 -> x1 + y1 == x2 + y2; + SRmul_ext : + forall x1 x2, x1 == x2 -> forall y1 y2, y1 == y2 -> x1 * y1 == x2 * y2 + }. + + Record ring_eq_ext : Prop := mk_reqe { + (* Ring operators are compatible with equality *) + Radd_ext : + forall x1 x2, x1 == x2 -> forall y1 y2, y1 == y2 -> x1 + y1 == x2 + y2; + Rmul_ext : + forall x1 x2, x1 == x2 -> forall y1 y2, y1 == y2 -> x1 * y1 == x2 * y2; + Ropp_ext : forall x1 x2, x1 == x2 -> -x1 == -x2 + }. + + (** Interpretation morphisms definition*) + Section MORPHISM. + Variable C:Type. + Variable (cO cI : C) (cadd cmul csub : C->C->C) (copp : C->C). + Variable ceqb : C->C->bool. + (* [phi] est un morphisme de [C] dans [R] *) + Variable phi : C -> R. + Notation "x +! y" := (cadd x y). Notation "x -! y " := (csub x y). + Notation "x *! y " := (cmul x y). Notation "-! x" := (copp x). + Notation "x ?=! y" := (ceqb x y). Notation "[ x ]" := (phi x). + +(*for semi rings*) + Record semi_morph : Prop := mkRmorph { + Smorph0 : [cO] == 0; + Smorph1 : [cI] == 1; + Smorph_add : forall x y, [x +! y] == [x]+[y]; + Smorph_mul : forall x y, [x *! y] == [x]*[y]; + Smorph_eq : forall x y, x?=!y = true -> [x] == [y] + }. + +(* for rings*) + Record ring_morph : Prop := mkmorph { + morph0 : [cO] == 0; + morph1 : [cI] == 1; + morph_add : forall x y, [x +! y] == [x]+[y]; + morph_sub : forall x y, [x -! y] == [x]-[y]; + morph_mul : forall x y, [x *! y] == [x]*[y]; + morph_opp : forall x, [-!x] == -[x]; + morph_eq : forall x y, x?=!y = true -> [x] == [y] + }. + + Section SIGN. + Variable get_sign : C -> option C. + Record sign_theory : Prop := mksign_th { + sign_spec : forall c c', get_sign c = Some c' -> c ?=! -! c' = true + }. + End SIGN. + + Definition get_sign_None (c:C) := @None C. + + Lemma get_sign_None_th : sign_theory get_sign_None. + Proof. constructor;intros;discriminate. Qed. + + Section DIV. + Variable cdiv: C -> C -> C*C. + Record div_theory : Prop := mkdiv_th { + div_eucl_th : forall a b, let (q,r) := cdiv a b in [a] == [b *! q +! r] + }. + End DIV. + + End MORPHISM. + + (** Identity is a morphism *) + Variable Rsth : Setoid_Theory R req. + Add Setoid R req Rsth as R_setoid1. + Variable reqb : R->R->bool. + Hypothesis morph_req : forall x y, (reqb x y) = true -> x == y. + Definition IDphi (x:R) := x. + Lemma IDmorph : ring_morph rO rI radd rmul rsub ropp reqb IDphi. + Proof. + apply (mkmorph rO rI radd rmul rsub ropp reqb IDphi);intros;unfold IDphi; + try apply (Seq_refl _ _ Rsth);auto. + Qed. + + (** Specification of the power function *) + Section POWER. + Variable Cpow : Set. + Variable Cp_phi : N -> Cpow. + Variable rpow : R -> Cpow -> R. + + Record power_theory : Prop := mkpow_th { + rpow_pow_N : forall r n, req (rpow r (Cp_phi n)) (pow_N rI rmul r n) + }. + + End POWER. + + Definition pow_N_th := mkpow_th id_phi_N (pow_N rI rmul) (pow_N_pow_N rI rmul Rsth). + + +End DEFINITIONS. + + + +Section ALMOST_RING. + Variable R : Type. + Variable (rO rI : R) (radd rmul rsub: R->R->R) (ropp : R -> R). + Variable req : R -> R -> Prop. + Notation "0" := rO. Notation "1" := rI. + Notation "x + y" := (radd x y). Notation "x * y " := (rmul x y). + Notation "x - y " := (rsub x y). Notation "- x" := (ropp x). + Notation "x == y" := (req x y). + + (** Leibniz equality leads to a setoid theory and is extensional*) + Lemma Eqsth : Setoid_Theory R (@eq R). + Proof. constructor;red;intros;subst;trivial. Qed. + + Lemma Eq_s_ext : sring_eq_ext radd rmul (@eq R). + Proof. constructor;intros;subst;trivial. Qed. + + Lemma Eq_ext : ring_eq_ext radd rmul ropp (@eq R). + Proof. constructor;intros;subst;trivial. Qed. + + Variable Rsth : Setoid_Theory R req. + Add Setoid R req Rsth as R_setoid2. + Ltac sreflexivity := apply (Seq_refl _ _ Rsth). + + Section SEMI_RING. + Variable SReqe : sring_eq_ext radd rmul req. + Add Morphism radd : radd_ext1. exact (SRadd_ext SReqe). Qed. + Add Morphism rmul : rmul_ext1. exact (SRmul_ext SReqe). Qed. + Variable SRth : semi_ring_theory 0 1 radd rmul req. + + (** Every semi ring can be seen as an almost ring, by taking : + -x = x and x - y = x + y *) + Definition SRopp (x:R) := x. Notation "- x" := (SRopp x). + + Definition SRsub x y := x + -y. Notation "x - y " := (SRsub x y). + + Lemma SRopp_ext : forall x y, x == y -> -x == -y. + Proof. intros x y H;exact H. Qed. + + Lemma SReqe_Reqe : ring_eq_ext radd rmul SRopp req. + Proof. + constructor. exact (SRadd_ext SReqe). exact (SRmul_ext SReqe). + exact SRopp_ext. + Qed. + + Lemma SRopp_mul_l : forall x y, -(x * y) == -x * y. + Proof. intros;sreflexivity. Qed. + + Lemma SRopp_add : forall x y, -(x + y) == -x + -y. + Proof. intros;sreflexivity. Qed. + + + Lemma SRsub_def : forall x y, x - y == x + -y. + Proof. intros;sreflexivity. Qed. + + Lemma SRth_ARth : almost_ring_theory 0 1 radd rmul SRsub SRopp req. + Proof (mk_art 0 1 radd rmul SRsub SRopp req + (SRadd_0_l SRth) (SRadd_comm SRth) (SRadd_assoc SRth) + (SRmul_1_l SRth) (SRmul_0_l SRth) + (SRmul_comm SRth) (SRmul_assoc SRth) (SRdistr_l SRth) + SRopp_mul_l SRopp_add SRsub_def). + + (** Identity morphism for semi-ring equipped with their almost-ring structure*) + Variable reqb : R->R->bool. + + Hypothesis morph_req : forall x y, (reqb x y) = true -> x == y. + + Definition SRIDmorph : ring_morph 0 1 radd rmul SRsub SRopp req + 0 1 radd rmul SRsub SRopp reqb (@IDphi R). + Proof. + apply mkmorph;intros;try sreflexivity. unfold IDphi;auto. + Qed. + + (* a semi_morph can be extended to a ring_morph for the almost_ring derived + from a semi_ring, provided the ring is a setoid (we only need + reflexivity) *) + Variable C : Type. + Variable (cO cI : C) (cadd cmul: C->C->C). + Variable (ceqb : C -> C -> bool). + Variable phi : C -> R. + Variable Smorph : semi_morph rO rI radd rmul req cO cI cadd cmul ceqb phi. + + Lemma SRmorph_Rmorph : + ring_morph rO rI radd rmul SRsub SRopp req + cO cI cadd cmul cadd (fun x => x) ceqb phi. + Proof. + case Smorph; intros; constructor; auto. + unfold SRopp in |- *; intros. + setoid_reflexivity. + Qed. + + End SEMI_RING. + + Variable Reqe : ring_eq_ext radd rmul ropp req. + Add Morphism radd : radd_ext2. exact (Radd_ext Reqe). Qed. + Add Morphism rmul : rmul_ext2. exact (Rmul_ext Reqe). Qed. + Add Morphism ropp : ropp_ext2. exact (Ropp_ext Reqe). Qed. + + Section RING. + Variable Rth : ring_theory 0 1 radd rmul rsub ropp req. + + (** Rings are almost rings*) + Lemma Rmul_0_l : forall x, 0 * x == 0. + Proof. + intro x; setoid_replace (0*x) with ((0+1)*x + -x). + rewrite (Radd_0_l Rth); rewrite (Rmul_1_l Rth). + rewrite (Ropp_def Rth);sreflexivity. + + rewrite (Rdistr_l Rth);rewrite (Rmul_1_l Rth). + rewrite <- (Radd_assoc Rth); rewrite (Ropp_def Rth). + rewrite (Radd_comm Rth); rewrite (Radd_0_l Rth);sreflexivity. + Qed. + + Lemma Ropp_mul_l : forall x y, -(x * y) == -x * y. + Proof. + intros x y;rewrite <-(Radd_0_l Rth (- x * y)). + rewrite (Radd_comm Rth). + rewrite <-(Ropp_def Rth (x*y)). + rewrite (Radd_assoc Rth). + rewrite <- (Rdistr_l Rth). + rewrite (Rth.(Radd_comm) (-x));rewrite (Ropp_def Rth). + rewrite Rmul_0_l;rewrite (Radd_0_l Rth);sreflexivity. + Qed. + + Lemma Ropp_add : forall x y, -(x + y) == -x + -y. + Proof. + intros x y;rewrite <- ((Radd_0_l Rth) (-(x+y))). + rewrite <- ((Ropp_def Rth) x). + rewrite <- ((Radd_0_l Rth) (x + - x + - (x + y))). + rewrite <- ((Ropp_def Rth) y). + rewrite ((Radd_comm Rth) x). + rewrite ((Radd_comm Rth) y). + rewrite <- ((Radd_assoc Rth) (-y)). + rewrite <- ((Radd_assoc Rth) (- x)). + rewrite ((Radd_assoc Rth) y). + rewrite ((Radd_comm Rth) y). + rewrite <- ((Radd_assoc Rth) (- x)). + rewrite ((Radd_assoc Rth) y). + rewrite ((Radd_comm Rth) y);rewrite (Ropp_def Rth). + rewrite ((Radd_comm Rth) (-x) 0);rewrite (Radd_0_l Rth). + apply (Radd_comm Rth). + Qed. + + Lemma Ropp_opp : forall x, - -x == x. + Proof. + intros x; rewrite <- (Radd_0_l Rth (- -x)). + rewrite <- (Ropp_def Rth x). + rewrite <- (Radd_assoc Rth); rewrite (Ropp_def Rth). + rewrite ((Radd_comm Rth) x);apply (Radd_0_l Rth). + Qed. + + Lemma Rth_ARth : almost_ring_theory 0 1 radd rmul rsub ropp req. + Proof + (mk_art 0 1 radd rmul rsub ropp req (Radd_0_l Rth) (Radd_comm Rth) (Radd_assoc Rth) + (Rmul_1_l Rth) Rmul_0_l (Rmul_comm Rth) (Rmul_assoc Rth) (Rdistr_l Rth) + Ropp_mul_l Ropp_add (Rsub_def Rth)). + + (** Every semi morphism between two rings is a morphism*) + Variable C : Type. + Variable (cO cI : C) (cadd cmul csub: C->C->C) (copp : C -> C). + Variable (ceq : C -> C -> Prop) (ceqb : C -> C -> bool). + Variable phi : C -> R. + Notation "x +! y" := (cadd x y). Notation "x *! y " := (cmul x y). + Notation "x -! y " := (csub x y). Notation "-! x" := (copp x). + Notation "x ?=! y" := (ceqb x y). Notation "[ x ]" := (phi x). + Variable Csth : Setoid_Theory C ceq. + Variable Ceqe : ring_eq_ext cadd cmul copp ceq. + Add Setoid C ceq Csth as C_setoid. + Add Morphism cadd : cadd_ext. exact (Radd_ext Ceqe). Qed. + Add Morphism cmul : cmul_ext. exact (Rmul_ext Ceqe). Qed. + Add Morphism copp : copp_ext. exact (Ropp_ext Ceqe). Qed. + Variable Cth : ring_theory cO cI cadd cmul csub copp ceq. + Variable Smorph : semi_morph 0 1 radd rmul req cO cI cadd cmul ceqb phi. + Variable phi_ext : forall x y, ceq x y -> [x] == [y]. + Add Morphism phi : phi_ext1. exact phi_ext. Qed. + Lemma Smorph_opp : forall x, [-!x] == -[x]. + Proof. + intros x;rewrite <- (Rth.(Radd_0_l) [-!x]). + rewrite <- ((Ropp_def Rth) [x]). + rewrite ((Radd_comm Rth) [x]). + rewrite <- (Radd_assoc Rth). + rewrite <- (Smorph_add Smorph). + rewrite (Ropp_def Cth). + rewrite (Smorph0 Smorph). + rewrite (Radd_comm Rth (-[x])). + apply (Radd_0_l Rth);sreflexivity. + Qed. + + Lemma Smorph_sub : forall x y, [x -! y] == [x] - [y]. + Proof. + intros x y; rewrite (Rsub_def Cth);rewrite (Rsub_def Rth). + rewrite (Smorph_add Smorph);rewrite Smorph_opp;sreflexivity. + Qed. + + Lemma Smorph_morph : ring_morph 0 1 radd rmul rsub ropp req + cO cI cadd cmul csub copp ceqb phi. + Proof + (mkmorph 0 1 radd rmul rsub ropp req cO cI cadd cmul csub copp ceqb phi + (Smorph0 Smorph) (Smorph1 Smorph) + (Smorph_add Smorph) Smorph_sub (Smorph_mul Smorph) Smorph_opp + (Smorph_eq Smorph)). + + End RING. + + (** Useful lemmas on almost ring *) + Variable ARth : almost_ring_theory 0 1 radd rmul rsub ropp req. + + Lemma ARth_SRth : semi_ring_theory 0 1 radd rmul req. +Proof. +elim ARth; intros. +constructor; trivial. +Qed. + + Lemma ARsub_ext : + forall x1 x2, x1 == x2 -> forall y1 y2, y1 == y2 -> x1 - y1 == x2 - y2. + Proof. + intros. + setoid_replace (x1 - y1) with (x1 + -y1). + setoid_replace (x2 - y2) with (x2 + -y2). + rewrite H;rewrite H0;sreflexivity. + apply (ARsub_def ARth). + apply (ARsub_def ARth). + Qed. + Add Morphism rsub : rsub_ext. exact ARsub_ext. Qed. + + Ltac mrewrite := + repeat first + [ rewrite (ARadd_0_l ARth) + | rewrite <- ((ARadd_comm ARth) 0) + | rewrite (ARmul_1_l ARth) + | rewrite <- ((ARmul_comm ARth) 1) + | rewrite (ARmul_0_l ARth) + | rewrite <- ((ARmul_comm ARth) 0) + | rewrite (ARdistr_l ARth) + | sreflexivity + | match goal with + | |- context [?z * (?x + ?y)] => rewrite ((ARmul_comm ARth) z (x+y)) + end]. + + Lemma ARadd_0_r : forall x, (x + 0) == x. + Proof. intros; mrewrite. Qed. + + Lemma ARmul_1_r : forall x, x * 1 == x. + Proof. intros;mrewrite. Qed. + + Lemma ARmul_0_r : forall x, x * 0 == 0. + Proof. intros;mrewrite. Qed. + + Lemma ARdistr_r : forall x y z, z * (x + y) == z*x + z*y. + Proof. + intros;mrewrite. + repeat rewrite (ARth.(ARmul_comm) z);sreflexivity. + Qed. + + Lemma ARadd_assoc1 : forall x y z, (x + y) + z == (y + z) + x. + Proof. + intros;rewrite <-(ARth.(ARadd_assoc) x). + rewrite (ARth.(ARadd_comm) x);sreflexivity. + Qed. + + Lemma ARadd_assoc2 : forall x y z, (y + x) + z == (y + z) + x. + Proof. + intros; repeat rewrite <- (ARadd_assoc ARth); + rewrite ((ARadd_comm ARth) x); sreflexivity. + Qed. + + Lemma ARmul_assoc1 : forall x y z, (x * y) * z == (y * z) * x. + Proof. + intros;rewrite <-((ARmul_assoc ARth) x). + rewrite ((ARmul_comm ARth) x);sreflexivity. + Qed. + + Lemma ARmul_assoc2 : forall x y z, (y * x) * z == (y * z) * x. + Proof. + intros; repeat rewrite <- (ARmul_assoc ARth); + rewrite ((ARmul_comm ARth) x); sreflexivity. + Qed. + + Lemma ARopp_mul_r : forall x y, - (x * y) == x * -y. + Proof. + intros;rewrite ((ARmul_comm ARth) x y); + rewrite (ARopp_mul_l ARth); apply (ARmul_comm ARth). + Qed. + + Lemma ARopp_zero : -0 == 0. + Proof. + rewrite <- (ARmul_0_r 0); rewrite (ARopp_mul_l ARth). + repeat rewrite ARmul_0_r; sreflexivity. + Qed. + + + +End ALMOST_RING. + + +Section AddRing. + +(* Variable R : Type. + Variable (rO rI : R) (radd rmul rsub: R->R->R) (ropp : R -> R). + Variable req : R -> R -> Prop. *) + +Inductive ring_kind : Type := +| Abstract +| Computational + (R:Type) + (req : R -> R -> Prop) + (reqb : R -> R -> bool) + (_ : forall x y, (reqb x y) = true -> req x y) +| Morphism + (R : Type) + (rO rI : R) (radd rmul rsub: R->R->R) (ropp : R -> R) + (req : R -> R -> Prop) + (C : Type) + (cO cI : C) (cadd cmul csub : C->C->C) (copp : C->C) + (ceqb : C->C->bool) + phi + (_ : ring_morph rO rI radd rmul rsub ropp req + cO cI cadd cmul csub copp ceqb phi). + + +End AddRing. + + +(** Some simplification tactics*) +Ltac gen_reflexivity Rsth := apply (Seq_refl _ _ Rsth). + +Ltac gen_srewrite Rsth Reqe ARth := + repeat first + [ gen_reflexivity Rsth + | progress rewrite (ARopp_zero Rsth Reqe ARth) + | rewrite (ARadd_0_l ARth) + | rewrite (ARadd_0_r Rsth ARth) + | rewrite (ARmul_1_l ARth) + | rewrite (ARmul_1_r Rsth ARth) + | rewrite (ARmul_0_l ARth) + | rewrite (ARmul_0_r Rsth ARth) + | rewrite (ARdistr_l ARth) + | rewrite (ARdistr_r Rsth Reqe ARth) + | rewrite (ARadd_assoc ARth) + | rewrite (ARmul_assoc ARth) + | progress rewrite (ARopp_add ARth) + | progress rewrite (ARsub_def ARth) + | progress rewrite <- (ARopp_mul_l ARth) + | progress rewrite <- (ARopp_mul_r Rsth Reqe ARth) ]. + +Ltac gen_add_push add Rsth Reqe ARth x := + repeat (match goal with + | |- context [add (add ?y x) ?z] => + progress rewrite (ARadd_assoc2 Rsth Reqe ARth x y z) + | |- context [add (add x ?y) ?z] => + progress rewrite (ARadd_assoc1 Rsth ARth x y z) + end). + +Ltac gen_mul_push mul Rsth Reqe ARth x := + repeat (match goal with + | |- context [mul (mul ?y x) ?z] => + progress rewrite (ARmul_assoc2 Rsth Reqe ARth x y z) + | |- context [mul (mul x ?y) ?z] => + progress rewrite (ARmul_assoc1 Rsth ARth x y z) + end). + diff --git a/plugins/setoid_ring/ZArithRing.v b/plugins/setoid_ring/ZArithRing.v new file mode 100644 index 00000000..4cb5a05a --- /dev/null +++ b/plugins/setoid_ring/ZArithRing.v @@ -0,0 +1,60 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* t + | _ => constr:NotConstant + end. + +Ltac isZpow_coef t := + match t with + | Zpos ?p => isPcst p + | Z0 => constr:true + | _ => constr:false + end. + +Definition N_of_Z x := + match x with + | Zpos p => Npos p + | _ => N0 + end. + +Ltac Zpow_tac t := + match isZpow_coef t with + | true => constr:(N_of_Z t) + | _ => constr:NotConstant + end. + +Ltac Zpower_neg := + repeat match goal with + | [|- ?G] => + match G with + | context c [Zpower _ (Zneg _)] => + let t := context c [Z0] in + change t + end + end. + +Add Ring Zr : Zth + (decidable Zeq_bool_eq, constants [Zcst], preprocess [Zpower_neg;unfold Zsucc], + power_tac Zpower_theory [Zpow_tac], + (* The two following option are not needed, it is the default chose when the set of + coefficiant is usual ring Z *) + div (InitialRing.Ztriv_div_th (@Eqsth Z) (@IDphi Z)), + sign get_signZ_th). + + diff --git a/plugins/setoid_ring/newring.ml4 b/plugins/setoid_ring/newring.ml4 new file mode 100644 index 00000000..535dbdbd --- /dev/null +++ b/plugins/setoid_ring/newring.ml4 @@ -0,0 +1,1164 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* f i c + | _ -> assert false + +type protect_flag = Eval|Prot|Rec + +let tag_arg tag_rec map subs i c = + match map i with + Eval -> mk_clos subs c + | Prot -> mk_atom c + | Rec -> if i = -1 then mk_clos subs c else tag_rec c + +let rec mk_clos_but f_map subs t = + match f_map t with + | Some map -> tag_arg (mk_clos_but f_map subs) map subs (-1) t + | None -> + (match kind_of_term t with + App(f,args) -> mk_clos_app_but f_map subs f args 0 + | Prod _ -> mk_clos_deep (mk_clos_but f_map) subs t + | _ -> mk_atom t) + +and mk_clos_app_but f_map subs f args n = + if n >= Array.length args then mk_atom(mkApp(f, args)) + else + let fargs, args' = array_chop n args in + let f' = mkApp(f,fargs) in + match f_map f' with + Some map -> + mk_clos_deep + (fun s' -> unmark_arg (tag_arg (mk_clos_but f_map s') map s')) + subs + (mkApp (mark_arg (-1) f', Array.mapi mark_arg args')) + | None -> mk_clos_app_but f_map subs f args (n+1) + + +let interp_map l c = + try + let (im,am) = List.assoc c l in + Some(fun i -> + if List.mem i im then Eval + else if List.mem i am then Prot + else if i = -1 then Eval + else Rec) + with Not_found -> None + +let interp_map l t = + try Some(List.assoc t l) with Not_found -> None + +let protect_maps = ref Stringmap.empty +let add_map s m = protect_maps := Stringmap.add s m !protect_maps +let lookup_map map = + try Stringmap.find map !protect_maps + with Not_found -> + errorlabstrm"lookup_map"(str"map "++qs map++str"not found") + +let protect_red map env sigma c = + kl (create_clos_infos betadeltaiota env) + (mk_clos_but (lookup_map map c) (Esubst.ESID 0) c);; + +let protect_tac map = + Tactics.reduct_option (protect_red map,DEFAULTcast) None ;; + +let protect_tac_in map id = + Tactics.reduct_option (protect_red map,DEFAULTcast) (Some(id,InHyp));; + + +TACTIC EXTEND protect_fv + [ "protect_fv" string(map) "in" ident(id) ] -> + [ protect_tac_in map id ] +| [ "protect_fv" string(map) ] -> + [ protect_tac map ] +END;; + +(****************************************************************************) + +let closed_term t l = + let l = List.map constr_of_global l in + let cs = List.fold_right Quote.ConstrSet.add l Quote.ConstrSet.empty in + if Quote.closed_under cs t then tclIDTAC else tclFAIL 0 (mt()) +;; + +TACTIC EXTEND closed_term + [ "closed_term" constr(t) "[" ne_reference_list(l) "]" ] -> + [ closed_term t l ] +END +;; + +TACTIC EXTEND echo +| [ "echo" constr(t) ] -> + [ Pp.msg (Termops.print_constr t); Tacinterp.eval_tactic (TacId []) ] +END;; + +(* +let closed_term_ast l = + TacFun([Some(id_of_string"t")], + TacAtom(dummy_loc,TacExtend(dummy_loc,"closed_term", + [Genarg.in_gen Genarg.wit_constr (mkVar(id_of_string"t")); + Genarg.in_gen (Genarg.wit_list1 Genarg.wit_ref) l]))) +*) +let closed_term_ast l = + let l = List.map (fun gr -> ArgArg(dummy_loc,gr)) l in + TacFun([Some(id_of_string"t")], + TacAtom(dummy_loc,TacExtend(dummy_loc,"closed_term", + [Genarg.in_gen Genarg.globwit_constr (RVar(dummy_loc,id_of_string"t"),None); + Genarg.in_gen (Genarg.wit_list1 Genarg.globwit_ref) l]))) +(* +let _ = add_tacdef false ((dummy_loc,id_of_string"ring_closed_term" +*) + +(****************************************************************************) + +let ic c = + let env = Global.env() and sigma = Evd.empty in + Constrintern.interp_constr sigma env c + +let ty c = Typing.type_of (Global.env()) Evd.empty c + +let decl_constant na c = + mkConst(declare_constant (id_of_string na) (DefinitionEntry + { const_entry_body = c; + const_entry_type = None; + const_entry_opaque = true; + const_entry_boxed = true}, + IsProof Lemma)) + +(* Calling a global tactic *) +let ltac_call tac (args:glob_tactic_arg list) = + TacArg(TacCall(dummy_loc, ArgArg(dummy_loc, Lazy.force tac),args)) + +(* Calling a locally bound tactic *) +let ltac_lcall tac args = + TacArg(TacCall(dummy_loc, ArgVar(dummy_loc, id_of_string tac),args)) + +let ltac_letin (x, e1) e2 = + TacLetIn(false,[(dummy_loc,id_of_string x),e1],e2) + +let ltac_apply (f:glob_tactic_expr) (args:glob_tactic_arg list) = + Tacinterp.eval_tactic + (ltac_letin ("F", Tacexp f) (ltac_lcall "F" args)) + +let ltac_record flds = + TacFun([Some(id_of_string"proj")], ltac_lcall "proj" flds) + + +let carg c = TacDynamic(dummy_loc,Pretyping.constr_in c) + +let dummy_goal env = + {Evd.it = Evd.make_evar (named_context_val env) mkProp; + Evd.sigma = Evd.empty} + +let exec_tactic env n f args = + let lid = list_tabulate(fun i -> id_of_string("x"^string_of_int i)) n in + let res = ref [||] in + let get_res ist = + let l = List.map (fun id -> List.assoc id ist.lfun) lid in + res := Array.of_list l; + TacId[] in + let getter = + Tacexp(TacFun(List.map(fun id -> Some id) lid, + glob_tactic(tacticIn get_res))) in + let _ = + Tacinterp.eval_tactic(ltac_call f (args@[getter])) (dummy_goal env) in + !res + +let constr_of = function + | VConstr ([],c) -> c + | _ -> failwith "Ring.exec_tactic: anomaly" + +let stdlib_modules = + [["Coq";"Setoids";"Setoid"]; + ["Coq";"Lists";"List"]; + ["Coq";"Init";"Datatypes"]; + ["Coq";"Init";"Logic"]; + ] + +let coq_constant c = + lazy (Coqlib.gen_constant_in_modules "Ring" stdlib_modules c) + +let coq_mk_Setoid = coq_constant "Build_Setoid_Theory" +let coq_cons = coq_constant "cons" +let coq_nil = coq_constant "nil" +let coq_None = coq_constant "None" +let coq_Some = coq_constant "Some" +let coq_eq = coq_constant "eq" + +let lapp f args = mkApp(Lazy.force f,args) + +let dest_rel0 t = + match kind_of_term t with + | App(f,args) when Array.length args >= 2 -> + let rel = mkApp(f,Array.sub args 0 (Array.length args - 2)) in + if closed0 rel then + (rel,args.(Array.length args - 2),args.(Array.length args - 1)) + else error "ring: cannot find relation (not closed)" + | _ -> error "ring: cannot find relation" + +let rec dest_rel t = + match kind_of_term t with + | Prod(_,_,c) -> dest_rel c + | _ -> dest_rel0 t + +(****************************************************************************) +(* Library linking *) + +let plugin_dir = "setoid_ring" + +let cdir = ["Coq";plugin_dir] +let plugin_modules = + List.map (fun d -> cdir@d) + [["Ring_theory"];["Ring_polynom"]; ["Ring_tac"];["InitialRing"]; + ["Field_tac"]; ["Field_theory"] + ] + +let my_constant c = + lazy (Coqlib.gen_constant_in_modules "Ring" plugin_modules c) + +let new_ring_path = + make_dirpath (List.map id_of_string ["Ring_tac";plugin_dir;"Coq"]) +let ltac s = + lazy(make_kn (MPfile new_ring_path) (make_dirpath []) (mk_label s)) +let znew_ring_path = + make_dirpath (List.map id_of_string ["InitialRing";plugin_dir;"Coq"]) +let zltac s = + lazy(make_kn (MPfile znew_ring_path) (make_dirpath []) (mk_label s)) + +let mk_cst l s = lazy (Coqlib.gen_constant "newring" l s);; +let pol_cst s = mk_cst [plugin_dir;"Ring_polynom"] s ;; + +(* Ring theory *) + +(* almost_ring defs *) +let coq_almost_ring_theory = my_constant "almost_ring_theory" + +(* setoid and morphism utilities *) +let coq_eq_setoid = my_constant "Eqsth" +let coq_eq_morph = my_constant "Eq_ext" +let coq_eq_smorph = my_constant "Eq_s_ext" + +(* ring -> almost_ring utilities *) +let coq_ring_theory = my_constant "ring_theory" +let coq_mk_reqe = my_constant "mk_reqe" + +(* semi_ring -> almost_ring utilities *) +let coq_semi_ring_theory = my_constant "semi_ring_theory" +let coq_mk_seqe = my_constant "mk_seqe" + +let ltac_inv_morph_gen = zltac"inv_gen_phi" +let ltac_inv_morphZ = zltac"inv_gen_phiZ" +let ltac_inv_morphN = zltac"inv_gen_phiN" +let ltac_inv_morphNword = zltac"inv_gen_phiNword" +let coq_abstract = my_constant"Abstract" +let coq_comp = my_constant"Computational" +let coq_morph = my_constant"Morphism" + +(* morphism *) +let coq_ring_morph = my_constant "ring_morph" +let coq_semi_morph = my_constant "semi_morph" + +(* power function *) +let ltac_inv_morph_nothing = zltac"inv_morph_nothing" +let coq_pow_N_pow_N = my_constant "pow_N_pow_N" + +(* hypothesis *) +let coq_mkhypo = my_constant "mkhypo" +let coq_hypo = my_constant "hypo" + +(* Equality: do not evaluate but make recursive call on both sides *) +let map_with_eq arg_map c = + let (req,_,_) = dest_rel c in + interp_map + ((req,(function -1->Prot|_->Rec)):: + List.map (fun (c,map) -> (Lazy.force c,map)) arg_map) + +let _ = add_map "ring" + (map_with_eq + [coq_cons,(function -1->Eval|2->Rec|_->Prot); + coq_nil, (function -1->Eval|_ -> Prot); + (* Pphi_dev: evaluate polynomial and coef operations, protect + ring operations and make recursive call on the var map *) + pol_cst "Pphi_dev", (function -1|8|9|10|11|12|14->Eval|13->Rec|_->Prot); + pol_cst "Pphi_pow", + (function -1|8|9|10|11|13|15|17->Eval|16->Rec|_->Prot); + (* PEeval: evaluate morphism and polynomial, protect ring + operations and make recursive call on the var map *) + pol_cst "PEeval", (function -1|7|9|12->Eval|11->Rec|_->Prot)]) + +(****************************************************************************) +(* Ring database *) + +type ring_info = + { ring_carrier : types; + ring_req : constr; + ring_setoid : constr; + ring_ext : constr; + ring_morph : constr; + ring_th : constr; + ring_cst_tac : glob_tactic_expr; + ring_pow_tac : glob_tactic_expr; + ring_lemma1 : constr; + ring_lemma2 : constr; + ring_pre_tac : glob_tactic_expr; + ring_post_tac : glob_tactic_expr } + +module Cmap = Map.Make(struct type t = constr let compare = compare end) + +let from_carrier = ref Cmap.empty +let from_relation = ref Cmap.empty +let from_name = ref Spmap.empty + +let ring_for_carrier r = Cmap.find r !from_carrier +let ring_for_relation rel = Cmap.find rel !from_relation + + +let find_ring_structure env sigma l = + match l with + | t::cl' -> + let ty = Retyping.get_type_of env sigma t in + let check c = + let ty' = Retyping.get_type_of env sigma c in + if not (Reductionops.is_conv env sigma ty ty') then + errorlabstrm "ring" + (str"arguments of ring_simplify do not have all the same type") + in + List.iter check cl'; + (try ring_for_carrier ty + with Not_found -> + errorlabstrm "ring" + (str"cannot find a declared ring structure over"++ + spc()++str"\""++pr_constr ty++str"\"")) + | [] -> assert false +(* + let (req,_,_) = dest_rel cl in + (try ring_for_relation req + with Not_found -> + errorlabstrm "ring" + (str"cannot find a declared ring structure for equality"++ + spc()++str"\""++pr_constr req++str"\"")) *) + +let _ = + Summary.declare_summary "tactic-new-ring-table" + { Summary.freeze_function = + (fun () -> !from_carrier,!from_relation,!from_name); + Summary.unfreeze_function = + (fun (ct,rt,nt) -> + from_carrier := ct; from_relation := rt; from_name := nt); + Summary.init_function = + (fun () -> + from_carrier := Cmap.empty; from_relation := Cmap.empty; + from_name := Spmap.empty) } + +let add_entry (sp,_kn) e = +(* let _ = ty e.ring_lemma1 in + let _ = ty e.ring_lemma2 in +*) + from_carrier := Cmap.add e.ring_carrier e !from_carrier; + from_relation := Cmap.add e.ring_req e !from_relation; + from_name := Spmap.add sp e !from_name + + +let subst_th (subst,th) = + let c' = subst_mps subst th.ring_carrier in + let eq' = subst_mps subst th.ring_req in + let set' = subst_mps subst th.ring_setoid in + let ext' = subst_mps subst th.ring_ext in + let morph' = subst_mps subst th.ring_morph in + let th' = subst_mps subst th.ring_th in + let thm1' = subst_mps subst th.ring_lemma1 in + let thm2' = subst_mps subst th.ring_lemma2 in + let tac'= subst_tactic subst th.ring_cst_tac in + let pow_tac'= subst_tactic subst th.ring_pow_tac in + let pretac'= subst_tactic subst th.ring_pre_tac in + let posttac'= subst_tactic subst th.ring_post_tac in + if c' == th.ring_carrier && + eq' == th.ring_req && + set' = th.ring_setoid && + ext' == th.ring_ext && + morph' == th.ring_morph && + th' == th.ring_th && + thm1' == th.ring_lemma1 && + thm2' == th.ring_lemma2 && + tac' == th.ring_cst_tac && + pow_tac' == th.ring_pow_tac && + pretac' == th.ring_pre_tac && + posttac' == th.ring_post_tac then th + else + { ring_carrier = c'; + ring_req = eq'; + ring_setoid = set'; + ring_ext = ext'; + ring_morph = morph'; + ring_th = th'; + ring_cst_tac = tac'; + ring_pow_tac = pow_tac'; + ring_lemma1 = thm1'; + ring_lemma2 = thm2'; + ring_pre_tac = pretac'; + ring_post_tac = posttac' } + + +let (theory_to_obj, obj_to_theory) = + let cache_th (name,th) = add_entry name th in + declare_object + {(default_object "tactic-new-ring-theory") with + open_function = (fun i o -> if i=1 then cache_th o); + cache_function = cache_th; + subst_function = subst_th; + classify_function = (fun x -> Substitute x)} + + +let setoid_of_relation env a r = + let evm = Evd.empty in + try + lapp coq_mk_Setoid + [|a ; r ; + Rewrite.get_reflexive_proof env evm a r ; + Rewrite.get_symmetric_proof env evm a r ; + Rewrite.get_transitive_proof env evm a r |] + with Not_found -> + error "cannot find setoid relation" + +let op_morph r add mul opp req m1 m2 m3 = + lapp coq_mk_reqe [| r; add; mul; opp; req; m1; m2; m3 |] + +let op_smorph r add mul req m1 m2 = + lapp coq_mk_seqe [| r; add; mul; req; m1; m2 |] + +(* let default_ring_equality (r,add,mul,opp,req) = *) +(* let is_setoid = function *) +(* {rel_refl=Some _; rel_sym=Some _;rel_trans=Some _;rel_aeq=rel} -> *) +(* eq_constr req rel (\* Qu: use conversion ? *\) *) +(* | _ -> false in *) +(* match default_relation_for_carrier ~filter:is_setoid r with *) +(* Leibniz _ -> *) +(* let setoid = lapp coq_eq_setoid [|r|] in *) +(* let op_morph = *) +(* match opp with *) +(* Some opp -> lapp coq_eq_morph [|r;add;mul;opp|] *) +(* | None -> lapp coq_eq_smorph [|r;add;mul|] in *) +(* (setoid,op_morph) *) +(* | Relation rel -> *) +(* let setoid = setoid_of_relation rel in *) +(* let is_endomorphism = function *) +(* { args=args } -> List.for_all *) +(* (function (var,Relation rel) -> *) +(* var=None && eq_constr req rel *) +(* | _ -> false) args in *) +(* let add_m = *) +(* try default_morphism ~filter:is_endomorphism add *) +(* with Not_found -> *) +(* error "ring addition should be declared as a morphism" in *) +(* let mul_m = *) +(* try default_morphism ~filter:is_endomorphism mul *) +(* with Not_found -> *) +(* error "ring multiplication should be declared as a morphism" in *) +(* let op_morph = *) +(* match opp with *) +(* | Some opp -> *) +(* (let opp_m = *) +(* try default_morphism ~filter:is_endomorphism opp *) +(* with Not_found -> *) +(* error "ring opposite should be declared as a morphism" in *) +(* let op_morph = *) +(* op_morph r add mul opp req add_m.lem mul_m.lem opp_m.lem in *) +(* msgnl *) +(* (str"Using setoid \""++pr_constr rel.rel_aeq++str"\""++spc()++ *) +(* str"and morphisms \""++pr_constr add_m.morphism_theory++ *) +(* str"\","++spc()++ str"\""++pr_constr mul_m.morphism_theory++ *) +(* str"\""++spc()++str"and \""++pr_constr opp_m.morphism_theory++ *) +(* str"\""); *) +(* op_morph) *) +(* | None -> *) +(* (msgnl *) +(* (str"Using setoid \""++pr_constr rel.rel_aeq++str"\"" ++ spc() ++ *) +(* str"and morphisms \""++pr_constr add_m.morphism_theory++ *) +(* str"\""++spc()++str"and \""++ *) +(* pr_constr mul_m.morphism_theory++str"\""); *) +(* op_smorph r add mul req add_m.lem mul_m.lem) in *) +(* (setoid,op_morph) *) + +let ring_equality (r,add,mul,opp,req) = + match kind_of_term req with + | App (f, [| _ |]) when eq_constr f (Lazy.force coq_eq) -> + let setoid = lapp coq_eq_setoid [|r|] in + let op_morph = + match opp with + Some opp -> lapp coq_eq_morph [|r;add;mul;opp|] + | None -> lapp coq_eq_smorph [|r;add;mul|] in + (setoid,op_morph) + | _ -> + let setoid = setoid_of_relation (Global.env ()) r req in + let signature = [Some (r,req);Some (r,req)],Some(r,req) in + let add_m, add_m_lem = + try Rewrite.default_morphism signature add + with Not_found -> + error "ring addition should be declared as a morphism" in + let mul_m, mul_m_lem = + try Rewrite.default_morphism signature mul + with Not_found -> + error "ring multiplication should be declared as a morphism" in + let op_morph = + match opp with + | Some opp -> + (let opp_m,opp_m_lem = + try Rewrite.default_morphism ([Some(r,req)],Some(r,req)) opp + with Not_found -> + error "ring opposite should be declared as a morphism" in + let op_morph = + op_morph r add mul opp req add_m_lem mul_m_lem opp_m_lem in + Flags.if_verbose + msgnl + (str"Using setoid \""++pr_constr req++str"\""++spc()++ + str"and morphisms \""++pr_constr add_m_lem ++ + str"\","++spc()++ str"\""++pr_constr mul_m_lem++ + str"\""++spc()++str"and \""++pr_constr opp_m_lem++ + str"\""); + op_morph) + | None -> + (Flags.if_verbose + msgnl + (str"Using setoid \""++pr_constr req ++str"\"" ++ spc() ++ + str"and morphisms \""++pr_constr add_m_lem ++ + str"\""++spc()++str"and \""++ + pr_constr mul_m_lem++str"\""); + op_smorph r add mul req add_m_lem mul_m_lem) in + (setoid,op_morph) + +let build_setoid_params r add mul opp req eqth = + match eqth with + Some th -> th + | None -> ring_equality (r,add,mul,opp,req) + +let dest_ring env sigma th_spec = + let th_typ = Retyping.get_type_of env sigma th_spec in + match kind_of_term th_typ with + App(f,[|r;zero;one;add;mul;sub;opp;req|]) + when f = Lazy.force coq_almost_ring_theory -> + (None,r,zero,one,add,mul,Some sub,Some opp,req) + | App(f,[|r;zero;one;add;mul;req|]) + when f = Lazy.force coq_semi_ring_theory -> + (Some true,r,zero,one,add,mul,None,None,req) + | App(f,[|r;zero;one;add;mul;sub;opp;req|]) + when f = Lazy.force coq_ring_theory -> + (Some false,r,zero,one,add,mul,Some sub,Some opp,req) + | _ -> error "bad ring structure" + + +let dest_morph env sigma m_spec = + let m_typ = Retyping.get_type_of env sigma m_spec in + match kind_of_term m_typ with + App(f,[|r;zero;one;add;mul;sub;opp;req; + c;czero;cone;cadd;cmul;csub;copp;ceqb;phi|]) + when f = Lazy.force coq_ring_morph -> + (c,czero,cone,cadd,cmul,Some csub,Some copp,ceqb,phi) + | App(f,[|r;zero;one;add;mul;req;c;czero;cone;cadd;cmul;ceqb;phi|]) + when f = Lazy.force coq_semi_morph -> + (c,czero,cone,cadd,cmul,None,None,ceqb,phi) + | _ -> error "bad morphism structure" + + +type coeff_spec = + Computational of constr (* equality test *) + | Abstract (* coeffs = Z *) + | Morphism of constr (* general morphism *) + + +let reflect_coeff rkind = + (* We build an ill-typed terms on purpose... *) + match rkind with + Abstract -> Lazy.force coq_abstract + | Computational c -> lapp coq_comp [|c|] + | Morphism m -> lapp coq_morph [|m|] + +type cst_tac_spec = + CstTac of raw_tactic_expr + | Closed of reference list + +let interp_cst_tac env sigma rk kind (zero,one,add,mul,opp) cst_tac = + match cst_tac with + Some (CstTac t) -> Tacinterp.glob_tactic t + | Some (Closed lc) -> + closed_term_ast (List.map Smartlocate.global_with_alias lc) + | None -> + (match rk, opp, kind with + Abstract, None, _ -> + let t = ArgArg(dummy_loc,Lazy.force ltac_inv_morphN) in + TacArg(TacCall(dummy_loc,t,List.map carg [zero;one;add;mul])) + | Abstract, Some opp, Some _ -> + let t = ArgArg(dummy_loc, Lazy.force ltac_inv_morphZ) in + TacArg(TacCall(dummy_loc,t,List.map carg [zero;one;add;mul;opp])) + | Abstract, Some opp, None -> + let t = ArgArg(dummy_loc, Lazy.force ltac_inv_morphNword) in + TacArg + (TacCall(dummy_loc,t,List.map carg [zero;one;add;mul;opp])) + | Computational _,_,_ -> + let t = ArgArg(dummy_loc, Lazy.force ltac_inv_morph_gen) in + TacArg + (TacCall(dummy_loc,t,List.map carg [zero;one;zero;one])) + | Morphism mth,_,_ -> + let (_,czero,cone,_,_,_,_,_,_) = dest_morph env sigma mth in + let t = ArgArg(dummy_loc, Lazy.force ltac_inv_morph_gen) in + TacArg + (TacCall(dummy_loc,t,List.map carg [zero;one;czero;cone]))) + +let make_hyp env c = + let t = Retyping.get_type_of env Evd.empty c in + lapp coq_mkhypo [|t;c|] + +let make_hyp_list env lH = + let carrier = Lazy.force coq_hypo in + List.fold_right + (fun c l -> lapp coq_cons [|carrier; (make_hyp env c); l|]) lH + (lapp coq_nil [|carrier|]) + +let interp_power env pow = + let carrier = Lazy.force coq_hypo in + match pow with + | None -> + let t = ArgArg(dummy_loc, Lazy.force ltac_inv_morph_nothing) in + (TacArg(TacCall(dummy_loc,t,[])), lapp coq_None [|carrier|]) + | Some (tac, spec) -> + let tac = + match tac with + | CstTac t -> Tacinterp.glob_tactic t + | Closed lc -> + closed_term_ast (List.map Smartlocate.global_with_alias lc) in + let spec = make_hyp env (ic spec) in + (tac, lapp coq_Some [|carrier; spec|]) + +let interp_sign env sign = + let carrier = Lazy.force coq_hypo in + match sign with + | None -> lapp coq_None [|carrier|] + | Some spec -> + let spec = make_hyp env (ic spec) in + lapp coq_Some [|carrier;spec|] + (* Same remark on ill-typed terms ... *) + +let interp_div env div = + let carrier = Lazy.force coq_hypo in + match div with + | None -> lapp coq_None [|carrier|] + | Some spec -> + let spec = make_hyp env (ic spec) in + lapp coq_Some [|carrier;spec|] + (* Same remark on ill-typed terms ... *) + +let add_theory name rth eqth morphth cst_tac (pre,post) power sign div = + check_required_library (cdir@["Ring_base"]); + let env = Global.env() in + let sigma = Evd.empty in + let (kind,r,zero,one,add,mul,sub,opp,req) = dest_ring env sigma rth in + let (sth,ext) = build_setoid_params r add mul opp req eqth in + let (pow_tac, pspec) = interp_power env power in + let sspec = interp_sign env sign in + let dspec = interp_div env div in + let rk = reflect_coeff morphth in + let params = + exec_tactic env 5 (zltac "ring_lemmas") + (List.map carg[sth;ext;rth;pspec;sspec;dspec;rk]) in + let lemma1 = constr_of params.(3) in + let lemma2 = constr_of params.(4) in + + let lemma1 = decl_constant (string_of_id name^"_ring_lemma1") lemma1 in + let lemma2 = decl_constant (string_of_id name^"_ring_lemma2") lemma2 in + let cst_tac = + interp_cst_tac env sigma morphth kind (zero,one,add,mul,opp) cst_tac in + let pretac = + match pre with + Some t -> Tacinterp.glob_tactic t + | _ -> TacId [] in + let posttac = + match post with + Some t -> Tacinterp.glob_tactic t + | _ -> TacId [] in + let _ = + Lib.add_leaf name + (theory_to_obj + { ring_carrier = r; + ring_req = req; + ring_setoid = sth; + ring_ext = constr_of params.(1); + ring_morph = constr_of params.(2); + ring_th = constr_of params.(0); + ring_cst_tac = cst_tac; + ring_pow_tac = pow_tac; + ring_lemma1 = lemma1; + ring_lemma2 = lemma2; + ring_pre_tac = pretac; + ring_post_tac = posttac }) in + () + +type ring_mod = + Ring_kind of coeff_spec + | Const_tac of cst_tac_spec + | Pre_tac of raw_tactic_expr + | Post_tac of raw_tactic_expr + | Setoid of Topconstr.constr_expr * Topconstr.constr_expr + | Pow_spec of cst_tac_spec * Topconstr.constr_expr + (* Syntaxification tactic , correctness lemma *) + | Sign_spec of Topconstr.constr_expr + | Div_spec of Topconstr.constr_expr + + +VERNAC ARGUMENT EXTEND ring_mod + | [ "decidable" constr(eq_test) ] -> [ Ring_kind(Computational (ic eq_test)) ] + | [ "abstract" ] -> [ Ring_kind Abstract ] + | [ "morphism" constr(morph) ] -> [ Ring_kind(Morphism (ic morph)) ] + | [ "constants" "[" tactic(cst_tac) "]" ] -> [ Const_tac(CstTac cst_tac) ] + | [ "closed" "[" ne_global_list(l) "]" ] -> [ Const_tac(Closed l) ] + | [ "preprocess" "[" tactic(pre) "]" ] -> [ Pre_tac pre ] + | [ "postprocess" "[" tactic(post) "]" ] -> [ Post_tac post ] + | [ "setoid" constr(sth) constr(ext) ] -> [ Setoid(sth,ext) ] + | [ "sign" constr(sign_spec) ] -> [ Sign_spec sign_spec ] + | [ "power" constr(pow_spec) "[" ne_global_list(l) "]" ] -> + [ Pow_spec (Closed l, pow_spec) ] + | [ "power_tac" constr(pow_spec) "[" tactic(cst_tac) "]" ] -> + [ Pow_spec (CstTac cst_tac, pow_spec) ] + | [ "div" constr(div_spec) ] -> [ Div_spec div_spec ] +END + +let set_once s r v = + if !r = None then r := Some v else error (s^" cannot be set twice") + +let process_ring_mods l = + let kind = ref None in + let set = ref None in + let cst_tac = ref None in + let pre = ref None in + let post = ref None in + let sign = ref None in + let power = ref None in + let div = ref None in + List.iter(function + Ring_kind k -> set_once "ring kind" kind k + | Const_tac t -> set_once "tactic recognizing constants" cst_tac t + | Pre_tac t -> set_once "preprocess tactic" pre t + | Post_tac t -> set_once "postprocess tactic" post t + | Setoid(sth,ext) -> set_once "setoid" set (ic sth,ic ext) + | Pow_spec(t,spec) -> set_once "power" power (t,spec) + | Sign_spec t -> set_once "sign" sign t + | Div_spec t -> set_once "div" div t) l; + let k = match !kind with Some k -> k | None -> Abstract in + (k, !set, !cst_tac, !pre, !post, !power, !sign, !div) + +VERNAC COMMAND EXTEND AddSetoidRing + | [ "Add" "Ring" ident(id) ":" constr(t) ring_mods(l) ] -> + [ let (k,set,cst,pre,post,power,sign, div) = process_ring_mods l in + add_theory id (ic t) set k cst (pre,post) power sign div] +END + +(*****************************************************************************) +(* The tactics consist then only in a lookup in the ring database and + call the appropriate ltac. *) + +let make_args_list rl t = + match rl with + | [] -> let (_,t1,t2) = dest_rel0 t in [t1;t2] + | _ -> rl + +let make_term_list carrier rl = + List.fold_right + (fun x l -> lapp coq_cons [|carrier;x;l|]) rl + (lapp coq_nil [|carrier|]) + +let ltac_ring_structure e = + let req = carg e.ring_req in + let sth = carg e.ring_setoid in + let ext = carg e.ring_ext in + let morph = carg e.ring_morph in + let th = carg e.ring_th in + let cst_tac = Tacexp e.ring_cst_tac in + let pow_tac = Tacexp e.ring_pow_tac in + let lemma1 = carg e.ring_lemma1 in + let lemma2 = carg e.ring_lemma2 in + let pretac = Tacexp(TacFun([None],e.ring_pre_tac)) in + let posttac = Tacexp(TacFun([None],e.ring_post_tac)) in + [req;sth;ext;morph;th;cst_tac;pow_tac; + lemma1;lemma2;pretac;posttac] + +let ring_lookup (f:glob_tactic_expr) lH rl t gl = + let env = pf_env gl in + let sigma = project gl in + let rl = make_args_list rl t in + let e = find_ring_structure env sigma rl in + let rl = carg (make_term_list e.ring_carrier rl) in + let lH = carg (make_hyp_list env lH) in + let ring = ltac_ring_structure e in + ltac_apply f (ring@[lH;rl]) gl + +TACTIC EXTEND ring_lookup +| [ "ring_lookup" tactic0(f) "[" constr_list(lH) "]" ne_constr_list(lrt) ] -> + [ let (t,lr) = list_sep_last lrt in ring_lookup (fst f) lH lr t] +END + + + +(***********************************************************************) + +let new_field_path = + make_dirpath (List.map id_of_string ["Field_tac";plugin_dir;"Coq"]) + +let field_ltac s = + lazy(make_kn (MPfile new_field_path) (make_dirpath []) (mk_label s)) + + +let _ = add_map "field" + (map_with_eq + [coq_cons,(function -1->Eval|2->Rec|_->Prot); + coq_nil, (function -1->Eval|_ -> Prot); + (* display_linear: evaluate polynomials and coef operations, protect + field operations and make recursive call on the var map *) + my_constant "display_linear", + (function -1|9|10|11|12|13|15|16->Eval|14->Rec|_->Prot); + my_constant "display_pow_linear", + (function -1|9|10|11|12|13|14|16|18|19->Eval|17->Rec|_->Prot); + (* Pphi_dev: evaluate polynomial and coef operations, protect + ring operations and make recursive call on the var map *) + pol_cst "Pphi_dev", (function -1|8|9|10|11|12|14->Eval|13->Rec|_->Prot); + pol_cst "Pphi_pow", + (function -1|8|9|10|11|13|15|17->Eval|16->Rec|_->Prot); + (* PEeval: evaluate morphism and polynomial, protect ring + operations and make recursive call on the var map *) + pol_cst "PEeval", (function -1|7|9|12->Eval|11->Rec|_->Prot); + (* FEeval: evaluate morphism, protect field + operations and make recursive call on the var map *) + my_constant "FEeval", (function -1|8|9|10|11|14->Eval|13->Rec|_->Prot)]);; + +let _ = add_map "field_cond" + (map_with_eq + [coq_cons,(function -1->Eval|2->Rec|_->Prot); + coq_nil, (function -1->Eval|_ -> Prot); + (* PCond: evaluate morphism and denum list, protect ring + operations and make recursive call on the var map *) + my_constant "PCond", (function -1|8|10|13->Eval|12->Rec|_->Prot)]);; +(* (function -1|8|10->Eval|9->Rec|_->Prot)]);;*) + + +let _ = Redexpr.declare_reduction "simpl_field_expr" + (protect_red "field") + + + +let afield_theory = my_constant "almost_field_theory" +let field_theory = my_constant "field_theory" +let sfield_theory = my_constant "semi_field_theory" +let af_ar = my_constant"AF_AR" +let f_r = my_constant"F_R" +let sf_sr = my_constant"SF_SR" +let dest_field env sigma th_spec = + let th_typ = Retyping.get_type_of env sigma th_spec in + match kind_of_term th_typ with + | App(f,[|r;zero;one;add;mul;sub;opp;div;inv;req|]) + when f = Lazy.force afield_theory -> + let rth = lapp af_ar + [|r;zero;one;add;mul;sub;opp;div;inv;req;th_spec|] in + (None,r,zero,one,add,mul,Some sub,Some opp,div,inv,req,rth) + | App(f,[|r;zero;one;add;mul;sub;opp;div;inv;req|]) + when f = Lazy.force field_theory -> + let rth = + lapp f_r + [|r;zero;one;add;mul;sub;opp;div;inv;req;th_spec|] in + (Some false,r,zero,one,add,mul,Some sub,Some opp,div,inv,req,rth) + | App(f,[|r;zero;one;add;mul;div;inv;req|]) + when f = Lazy.force sfield_theory -> + let rth = lapp sf_sr + [|r;zero;one;add;mul;div;inv;req;th_spec|] in + (Some true,r,zero,one,add,mul,None,None,div,inv,req,rth) + | _ -> error "bad field structure" + +type field_info = + { field_carrier : types; + field_req : constr; + field_cst_tac : glob_tactic_expr; + field_pow_tac : glob_tactic_expr; + field_ok : constr; + field_simpl_eq_ok : constr; + field_simpl_ok : constr; + field_simpl_eq_in_ok : constr; + field_cond : constr; + field_pre_tac : glob_tactic_expr; + field_post_tac : glob_tactic_expr } + +let field_from_carrier = ref Cmap.empty +let field_from_relation = ref Cmap.empty +let field_from_name = ref Spmap.empty + + +let field_for_carrier r = Cmap.find r !field_from_carrier +let field_for_relation rel = Cmap.find rel !field_from_relation + +let find_field_structure env sigma l = + check_required_library (cdir@["Field_tac"]); + match l with + | t::cl' -> + let ty = Retyping.get_type_of env sigma t in + let check c = + let ty' = Retyping.get_type_of env sigma c in + if not (Reductionops.is_conv env sigma ty ty') then + errorlabstrm "field" + (str"arguments of field_simplify do not have all the same type") + in + List.iter check cl'; + (try field_for_carrier ty + with Not_found -> + errorlabstrm "field" + (str"cannot find a declared field structure over"++ + spc()++str"\""++pr_constr ty++str"\"")) + | [] -> assert false +(* let (req,_,_) = dest_rel cl in + (try field_for_relation req + with Not_found -> + errorlabstrm "field" + (str"cannot find a declared field structure for equality"++ + spc()++str"\""++pr_constr req++str"\"")) *) + +let _ = + Summary.declare_summary "tactic-new-field-table" + { Summary.freeze_function = + (fun () -> !field_from_carrier,!field_from_relation,!field_from_name); + Summary.unfreeze_function = + (fun (ct,rt,nt) -> + field_from_carrier := ct; field_from_relation := rt; + field_from_name := nt); + Summary.init_function = + (fun () -> + field_from_carrier := Cmap.empty; field_from_relation := Cmap.empty; + field_from_name := Spmap.empty) } + +let add_field_entry (sp,_kn) e = +(* + let _ = ty e.field_ok in + let _ = ty e.field_simpl_eq_ok in + let _ = ty e.field_simpl_ok in + let _ = ty e.field_cond in +*) + field_from_carrier := Cmap.add e.field_carrier e !field_from_carrier; + field_from_relation := Cmap.add e.field_req e !field_from_relation; + field_from_name := Spmap.add sp e !field_from_name + +let subst_th (subst,th) = + let c' = subst_mps subst th.field_carrier in + let eq' = subst_mps subst th.field_req in + let thm1' = subst_mps subst th.field_ok in + let thm2' = subst_mps subst th.field_simpl_eq_ok in + let thm3' = subst_mps subst th.field_simpl_ok in + let thm4' = subst_mps subst th.field_simpl_eq_in_ok in + let thm5' = subst_mps subst th.field_cond in + let tac'= subst_tactic subst th.field_cst_tac in + let pow_tac' = subst_tactic subst th.field_pow_tac in + let pretac'= subst_tactic subst th.field_pre_tac in + let posttac'= subst_tactic subst th.field_post_tac in + if c' == th.field_carrier && + eq' == th.field_req && + thm1' == th.field_ok && + thm2' == th.field_simpl_eq_ok && + thm3' == th.field_simpl_ok && + thm4' == th.field_simpl_eq_in_ok && + thm5' == th.field_cond && + tac' == th.field_cst_tac && + pow_tac' == th.field_pow_tac && + pretac' == th.field_pre_tac && + posttac' == th.field_post_tac then th + else + { field_carrier = c'; + field_req = eq'; + field_cst_tac = tac'; + field_pow_tac = pow_tac'; + field_ok = thm1'; + field_simpl_eq_ok = thm2'; + field_simpl_ok = thm3'; + field_simpl_eq_in_ok = thm4'; + field_cond = thm5'; + field_pre_tac = pretac'; + field_post_tac = posttac' } + +let (ftheory_to_obj, obj_to_ftheory) = + let cache_th (name,th) = add_field_entry name th in + declare_object + {(default_object "tactic-new-field-theory") with + open_function = (fun i o -> if i=1 then cache_th o); + cache_function = cache_th; + subst_function = subst_th; + classify_function = (fun x -> Substitute x) } + +let field_equality r inv req = + match kind_of_term req with + | App (f, [| _ |]) when eq_constr f (Lazy.force coq_eq) -> + mkApp((Coqlib.build_coq_eq_data()).congr,[|r;r;inv|]) + | _ -> + let _setoid = setoid_of_relation (Global.env ()) r req in + let signature = [Some (r,req)],Some(r,req) in + let inv_m, inv_m_lem = + try Rewrite.default_morphism signature inv + with Not_found -> + error "field inverse should be declared as a morphism" in + inv_m_lem + +let add_field_theory name fth eqth morphth cst_tac inj (pre,post) power sign odiv = + check_required_library (cdir@["Field_tac"]); + let env = Global.env() in + let sigma = Evd.empty in + let (kind,r,zero,one,add,mul,sub,opp,div,inv,req,rth) = + dest_field env sigma fth in + let (sth,ext) = build_setoid_params r add mul opp req eqth in + let eqth = Some(sth,ext) in + let _ = add_theory name rth eqth morphth cst_tac (None,None) power sign odiv in + let (pow_tac, pspec) = interp_power env power in + let sspec = interp_sign env sign in + let dspec = interp_div env odiv in + let inv_m = field_equality r inv req in + let rk = reflect_coeff morphth in + let params = + exec_tactic env 9 (field_ltac"field_lemmas") + (List.map carg[sth;ext;inv_m;fth;pspec;sspec;dspec;rk]) in + let lemma1 = constr_of params.(3) in + let lemma2 = constr_of params.(4) in + let lemma3 = constr_of params.(5) in + let lemma4 = constr_of params.(6) in + let cond_lemma = + match inj with + | Some thm -> mkApp(constr_of params.(8),[|thm|]) + | None -> constr_of params.(7) in + let lemma1 = decl_constant (string_of_id name^"_field_lemma1") lemma1 in + let lemma2 = decl_constant (string_of_id name^"_field_lemma2") lemma2 in + let lemma3 = decl_constant (string_of_id name^"_field_lemma3") lemma3 in + let lemma4 = decl_constant (string_of_id name^"_field_lemma4") lemma4 in + let cond_lemma = decl_constant (string_of_id name^"_lemma5") cond_lemma in + let cst_tac = + interp_cst_tac env sigma morphth kind (zero,one,add,mul,opp) cst_tac in + let pretac = + match pre with + Some t -> Tacinterp.glob_tactic t + | _ -> TacId [] in + let posttac = + match post with + Some t -> Tacinterp.glob_tactic t + | _ -> TacId [] in + let _ = + Lib.add_leaf name + (ftheory_to_obj + { field_carrier = r; + field_req = req; + field_cst_tac = cst_tac; + field_pow_tac = pow_tac; + field_ok = lemma1; + field_simpl_eq_ok = lemma2; + field_simpl_ok = lemma3; + field_simpl_eq_in_ok = lemma4; + field_cond = cond_lemma; + field_pre_tac = pretac; + field_post_tac = posttac }) in () + +type field_mod = + Ring_mod of ring_mod + | Inject of Topconstr.constr_expr + +VERNAC ARGUMENT EXTEND field_mod + | [ ring_mod(m) ] -> [ Ring_mod m ] + | [ "completeness" constr(inj) ] -> [ Inject inj ] +END + +let process_field_mods l = + let kind = ref None in + let set = ref None in + let cst_tac = ref None in + let pre = ref None in + let post = ref None in + let inj = ref None in + let sign = ref None in + let power = ref None in + let div = ref None in + List.iter(function + Ring_mod(Ring_kind k) -> set_once "field kind" kind k + | Ring_mod(Const_tac t) -> + set_once "tactic recognizing constants" cst_tac t + | Ring_mod(Pre_tac t) -> set_once "preprocess tactic" pre t + | Ring_mod(Post_tac t) -> set_once "postprocess tactic" post t + | Ring_mod(Setoid(sth,ext)) -> set_once "setoid" set (ic sth,ic ext) + | Ring_mod(Pow_spec(t,spec)) -> set_once "power" power (t,spec) + | Ring_mod(Sign_spec t) -> set_once "sign" sign t + | Ring_mod(Div_spec t) -> set_once "div" div t + | Inject i -> set_once "infinite property" inj (ic i)) l; + let k = match !kind with Some k -> k | None -> Abstract in + (k, !set, !inj, !cst_tac, !pre, !post, !power, !sign, !div) + +VERNAC COMMAND EXTEND AddSetoidField +| [ "Add" "Field" ident(id) ":" constr(t) field_mods(l) ] -> + [ let (k,set,inj,cst_tac,pre,post,power,sign,div) = process_field_mods l in + add_field_theory id (ic t) set k cst_tac inj (pre,post) power sign div] +END + + +let ltac_field_structure e = + let req = carg e.field_req in + let cst_tac = Tacexp e.field_cst_tac in + let pow_tac = Tacexp e.field_pow_tac in + let field_ok = carg e.field_ok in + let field_simpl_ok = carg e.field_simpl_ok in + let field_simpl_eq_ok = carg e.field_simpl_eq_ok in + let field_simpl_eq_in_ok = carg e.field_simpl_eq_in_ok in + let cond_ok = carg e.field_cond in + let pretac = Tacexp(TacFun([None],e.field_pre_tac)) in + let posttac = Tacexp(TacFun([None],e.field_post_tac)) in + [req;cst_tac;pow_tac;field_ok;field_simpl_ok;field_simpl_eq_ok; + field_simpl_eq_in_ok;cond_ok;pretac;posttac] + +let field_lookup (f:glob_tactic_expr) lH rl t gl = + let env = pf_env gl in + let sigma = project gl in + let rl = make_args_list rl t in + let e = find_field_structure env sigma rl in + let rl = carg (make_term_list e.field_carrier rl) in + let lH = carg (make_hyp_list env lH) in + let field = ltac_field_structure e in + ltac_apply f (field@[lH;rl]) gl + + +TACTIC EXTEND field_lookup +| [ "field_lookup" tactic(f) "[" constr_list(lH) "]" ne_constr_list(lt) ] -> + [ let (t,l) = list_sep_last lt in field_lookup (fst f) lH l t ] +END diff --git a/plugins/setoid_ring/newring_plugin.mllib b/plugins/setoid_ring/newring_plugin.mllib new file mode 100644 index 00000000..a98392f1 --- /dev/null +++ b/plugins/setoid_ring/newring_plugin.mllib @@ -0,0 +1,2 @@ +Newring +Newring_plugin_mod diff --git a/plugins/setoid_ring/vo.itarget b/plugins/setoid_ring/vo.itarget new file mode 100644 index 00000000..6934375b --- /dev/null +++ b/plugins/setoid_ring/vo.itarget @@ -0,0 +1,15 @@ +ArithRing.vo +BinList.vo +Field_tac.vo +Field_theory.vo +Field.vo +InitialRing.vo +NArithRing.vo +RealField.vo +Ring_base.vo +Ring_equiv.vo +Ring_polynom.vo +Ring_tac.vo +Ring_theory.vo +Ring.vo +ZArithRing.vo -- cgit v1.2.3