diff -r 1c9d5895d824 -r 309fc3f9cb8c Integ/Integ.ML --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Integ/Integ.ML Tue Feb 28 02:02:34 1995 +0100 @@ -0,0 +1,752 @@ +(* Title: Integ.ML + ID: $Id$ + Authors: Riccardo Mattolini, Dip. Sistemi e Informatica + Lawrence C Paulson, Cambridge University Computer Laboratory + Copyright 1994 Universita' di Firenze + Copyright 1993 University of Cambridge + +The integers as equivalence classes over nat*nat. + +Could also prove... +"znegative(z) ==> $# zmagnitude(z) = $~ z" +"~ znegative(z) ==> $# zmagnitude(z) = z" +< is a linear ordering ++ and * are monotonic wrt < +*) + +open Integ; + + +(*** Proving that intrel is an equivalence relation ***) + +val eqa::eqb::prems = goal Arith.thy + "[| (x1::nat) + y2 = x2 + y1; x2 + y3 = x3 + y2 |] ==> \ +\ x1 + y3 = x3 + y1"; +by (res_inst_tac [("k2","x2")] (add_left_cancel RS iffD1) 1); +by (rtac (add_left_commute RS trans) 1); +by (rtac (eqb RS ssubst) 1); +by (rtac (add_left_commute RS trans) 1); +by (rtac (eqa RS ssubst) 1); +by (rtac (add_left_commute) 1); +qed "integ_trans_lemma"; + +(** Natural deduction for intrel **) + +val prems = goalw Integ.thy [intrel_def] + "[| x1+y2 = x2+y1|] ==> \ +\ <,>: intrel"; +by (fast_tac (rel_cs addIs prems) 1); +qed "intrelI"; + +(*intrelE is hard to derive because fast_tac tries hyp_subst_tac so soon*) +goalw Integ.thy [intrel_def] + "p: intrel --> (EX x1 y1 x2 y2. \ +\ p = <,> & x1+y2 = x2+y1)"; +by (fast_tac rel_cs 1); +qed "intrelE_lemma"; + +val [major,minor] = goal Integ.thy + "[| p: intrel; \ +\ !!x1 y1 x2 y2. [| p = <,>; x1+y2 = x2+y1|] ==> Q |] \ +\ ==> Q"; +by (cut_facts_tac [major RS (intrelE_lemma RS mp)] 1); +by (REPEAT (eresolve_tac [asm_rl,exE,conjE,minor] 1)); +qed "intrelE"; + +val intrel_cs = rel_cs addSIs [intrelI] addSEs [intrelE]; + +goal Integ.thy "<,>: intrel = (x1+y2 = x2+y1)"; +by (fast_tac intrel_cs 1); +qed "intrel_iff"; + +goal Integ.thy ": intrel"; +by (rtac (surjective_pairing RS ssubst) 1 THEN rtac (refl RS intrelI) 1); +qed "intrel_refl"; + +goalw Integ.thy [equiv_def, refl_def, sym_def, trans_def] + "equiv({x::(nat*nat).True}, intrel)"; +by (fast_tac (intrel_cs addSIs [intrel_refl] + addSEs [sym, integ_trans_lemma]) 1); +qed "equiv_intrel"; + +val equiv_intrel_iff = + [TrueI, TrueI] MRS + ([CollectI, CollectI] MRS + (equiv_intrel RS eq_equiv_class_iff)); + +goalw Integ.thy [Integ_def,intrel_def,quotient_def] "intrel^^{}:Integ"; +by (fast_tac set_cs 1); +qed "intrel_in_integ"; + +goal Integ.thy "inj_onto(Abs_Integ,Integ)"; +by (rtac inj_onto_inverseI 1); +by (etac Abs_Integ_inverse 1); +qed "inj_onto_Abs_Integ"; + +val intrel_ss = + arith_ss addsimps [equiv_intrel_iff, inj_onto_Abs_Integ RS inj_onto_iff, + intrel_iff, intrel_in_integ, Abs_Integ_inverse]; + +goal Integ.thy "inj(Rep_Integ)"; +by (rtac inj_inverseI 1); +by (rtac Rep_Integ_inverse 1); +qed "inj_Rep_Integ"; + + + + +(** znat: the injection from nat to Integ **) + +goal Integ.thy "inj(znat)"; +by (rtac injI 1); +by (rewtac znat_def); +by (dtac (inj_onto_Abs_Integ RS inj_ontoD) 1); +by (REPEAT (rtac intrel_in_integ 1)); +by (dtac eq_equiv_class 1); +by (rtac equiv_intrel 1); +by (fast_tac set_cs 1); +by (safe_tac intrel_cs); +by (asm_full_simp_tac arith_ss 1); +qed "inj_znat"; + + +(**** zminus: unary negation on Integ ****) + +goalw Integ.thy [congruent_def] + "congruent(intrel,%p. split(%x y. intrel^^{},p))"; +by (safe_tac intrel_cs); +by (asm_simp_tac (intrel_ss addsimps add_ac) 1); +qed "zminus_congruent"; + + +(*Resolve th against the corresponding facts for zminus*) +val zminus_ize = RSLIST [equiv_intrel, zminus_congruent]; + +goalw Integ.thy [zminus_def] + "$~ Abs_Integ(intrel^^{}) = Abs_Integ(intrel ^^ {})"; +by (res_inst_tac [("f","Abs_Integ")] arg_cong 1); +by (simp_tac (set_ss addsimps + [intrel_in_integ RS Abs_Integ_inverse,zminus_ize UN_equiv_class]) 1); +by (rewtac split_def); +by (simp_tac prod_ss 1); +qed "zminus"; + +(*by lcp*) +val [prem] = goal Integ.thy + "(!!x y. z = Abs_Integ(intrel^^{}) ==> P) ==> P"; +by (res_inst_tac [("x1","z")] + (rewrite_rule [Integ_def] Rep_Integ RS quotientE) 1); +by (dres_inst_tac [("f","Abs_Integ")] arg_cong 1); +by (res_inst_tac [("p","x")] PairE 1); +by (rtac prem 1); +by (asm_full_simp_tac (HOL_ss addsimps [Rep_Integ_inverse]) 1); +qed "eq_Abs_Integ"; + +goal Integ.thy "$~ ($~ z) = z"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (asm_simp_tac (HOL_ss addsimps [zminus]) 1); +qed "zminus_zminus"; + +goal Integ.thy "inj(zminus)"; +by (rtac injI 1); +by (dres_inst_tac [("f","zminus")] arg_cong 1); +by (asm_full_simp_tac (HOL_ss addsimps [zminus_zminus]) 1); +qed "inj_zminus"; + +goalw Integ.thy [znat_def] "$~ ($#0) = $#0"; +by (simp_tac (arith_ss addsimps [zminus]) 1); +qed "zminus_0"; + + +(**** znegative: the test for negative integers ****) + +goal Arith.thy "!!m x n::nat. n+m=x ==> m<=x"; +by (dtac (disjI2 RS less_or_eq_imp_le) 1); +by (asm_full_simp_tac (arith_ss addsimps add_ac) 1); +by (dtac add_leD1 1); +by (assume_tac 1); +qed "not_znegative_znat_lemma"; + + +goalw Integ.thy [znegative_def, znat_def] + "~ znegative($# n)"; +by (simp_tac intrel_ss 1); +by (safe_tac intrel_cs); +by (rtac ccontr 1); +by (etac notE 1); +by (asm_full_simp_tac arith_ss 1); +by (dtac not_znegative_znat_lemma 1); +by (fast_tac (HOL_cs addDs [leD]) 1); +qed "not_znegative_znat"; + +goalw Integ.thy [znegative_def, znat_def] "znegative($~ $# Suc(n))"; +by (simp_tac (intrel_ss addsimps [zminus]) 1); +by (REPEAT (ares_tac [exI, conjI] 1)); +by (rtac (intrelI RS ImageI) 2); +by (rtac singletonI 3); +by (simp_tac arith_ss 2); +by (rtac less_add_Suc1 1); +qed "znegative_zminus_znat"; + + +(**** zmagnitude: magnitide of an integer, as a natural number ****) + +goal Arith.thy "!!n::nat. n - Suc(n+m)=0"; +by (nat_ind_tac "n" 1); +by (ALLGOALS(asm_simp_tac arith_ss)); +qed "diff_Suc_add_0"; + +goal Arith.thy "Suc((n::nat)+m)-n=Suc(m)"; +by (nat_ind_tac "n" 1); +by (ALLGOALS(asm_simp_tac arith_ss)); +qed "diff_Suc_add_inverse"; + +goalw Integ.thy [congruent_def] + "congruent(intrel, split(%x y. intrel^^{<(y-x) + (x-(y::nat)),0>}))"; +by (safe_tac intrel_cs); +by (asm_simp_tac intrel_ss 1); +by (etac rev_mp 1); +by (res_inst_tac [("m","x1"),("n","y1")] diff_induct 1); +by (asm_simp_tac (arith_ss addsimps [inj_Suc RS inj_eq]) 3); +by (asm_simp_tac (arith_ss addsimps [diff_add_inverse,diff_add_0]) 2); +by (asm_simp_tac arith_ss 1); +by (rtac impI 1); +by (etac subst 1); +by (res_inst_tac [("m1","x")] (add_commute RS ssubst) 1); +by (asm_simp_tac (arith_ss addsimps [diff_add_inverse,diff_add_0]) 1); +by (rtac impI 1); +by (asm_simp_tac (arith_ss addsimps + [diff_add_inverse, diff_add_0, diff_Suc_add_0, + diff_Suc_add_inverse]) 1); +qed "zmagnitude_congruent"; + +(*Resolve th against the corresponding facts for zmagnitude*) +val zmagnitude_ize = RSLIST [equiv_intrel, zmagnitude_congruent]; + + +goalw Integ.thy [zmagnitude_def] + "zmagnitude (Abs_Integ(intrel^^{})) = \ +\ Abs_Integ(intrel^^{<(y - x) + (x - y),0>})"; +by (res_inst_tac [("f","Abs_Integ")] arg_cong 1); +by (asm_simp_tac (intrel_ss addsimps [zmagnitude_ize UN_equiv_class]) 1); +qed "zmagnitude"; + +goalw Integ.thy [znat_def] "zmagnitude($# n) = $#n"; +by (asm_simp_tac (intrel_ss addsimps [zmagnitude]) 1); +qed "zmagnitude_znat"; + +goalw Integ.thy [znat_def] "zmagnitude($~ $# n) = $#n"; +by (asm_simp_tac (intrel_ss addsimps [zmagnitude, zminus]) 1); +qed "zmagnitude_zminus_znat"; + + +(**** zadd: addition on Integ ****) + +(** Congruence property for addition **) + +goalw Integ.thy [congruent2_def] + "congruent2(intrel, %p1 p2. \ +\ split(%x1 y1. split(%x2 y2. intrel^^{},p2),p1))"; +(*Proof via congruent2_commuteI seems longer*) +by (safe_tac intrel_cs); +by (asm_simp_tac (intrel_ss addsimps [add_assoc]) 1); +(*The rest should be trivial, but rearranging terms is hard*) +by (res_inst_tac [("x1","x1a")] (add_left_commute RS ssubst) 1); +by (asm_simp_tac (arith_ss addsimps [add_assoc RS sym]) 1); +by (asm_simp_tac (arith_ss addsimps add_ac) 1); +qed "zadd_congruent2"; + +(*Resolve th against the corresponding facts for zadd*) +val zadd_ize = RSLIST [equiv_intrel, zadd_congruent2]; + +goalw Integ.thy [zadd_def] + "Abs_Integ(intrel^^{}) + Abs_Integ(intrel^^{}) = \ +\ Abs_Integ(intrel^^{})"; +by (asm_simp_tac + (intrel_ss addsimps [zadd_ize UN_equiv_class2]) 1); +qed "zadd"; + +goalw Integ.thy [znat_def] "$#0 + z = z"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (asm_simp_tac (arith_ss addsimps [zadd]) 1); +qed "zadd_0"; + +goal Integ.thy "$~ (z + w) = $~ z + $~ w"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (asm_simp_tac (arith_ss addsimps [zminus,zadd]) 1); +qed "zminus_zadd_distrib"; + +goal Integ.thy "(z::int) + w = w + z"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (asm_simp_tac (intrel_ss addsimps (add_ac @ [zadd])) 1); +qed "zadd_commute"; + +goal Integ.thy "((z1::int) + z2) + z3 = z1 + (z2 + z3)"; +by (res_inst_tac [("z","z1")] eq_Abs_Integ 1); +by (res_inst_tac [("z","z2")] eq_Abs_Integ 1); +by (res_inst_tac [("z","z3")] eq_Abs_Integ 1); +by (asm_simp_tac (arith_ss addsimps [zadd, add_assoc]) 1); +qed "zadd_assoc"; + +(*For AC rewriting*) +goal Integ.thy "(x::int)+(y+z)=y+(x+z)"; +by (rtac (zadd_commute RS trans) 1); +by (rtac (zadd_assoc RS trans) 1); +by (rtac (zadd_commute RS arg_cong) 1); +qed "zadd_left_commute"; + +(*Integer addition is an AC operator*) +val zadd_ac = [zadd_assoc,zadd_commute,zadd_left_commute]; + +goalw Integ.thy [znat_def] "$# (m + n) = ($#m) + ($#n)"; +by (asm_simp_tac (arith_ss addsimps [zadd]) 1); +qed "znat_add"; + +goalw Integ.thy [znat_def] "z + ($~ z) = $#0"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (asm_simp_tac (intrel_ss addsimps [zminus, zadd, add_commute]) 1); +qed "zadd_zminus_inverse"; + +goal Integ.thy "($~ z) + z = $#0"; +by (rtac (zadd_commute RS trans) 1); +by (rtac zadd_zminus_inverse 1); +qed "zadd_zminus_inverse2"; + +goal Integ.thy "z + $#0 = z"; +by (rtac (zadd_commute RS trans) 1); +by (rtac zadd_0 1); +qed "zadd_0_right"; + + +(*Need properties of subtraction? Or use $- just as an abbreviation!*) + +(**** zmult: multiplication on Integ ****) + +(** Congruence property for multiplication **) + +goal Integ.thy "((k::nat) + l) + (m + n) = (k + m) + (n + l)"; +by (simp_tac (arith_ss addsimps add_ac) 1); +qed "zmult_congruent_lemma"; + +goal Integ.thy + "congruent2(intrel, %p1 p2. \ +\ split(%x1 y1. split(%x2 y2. \ +\ intrel^^{}, p2), p1))"; +by (rtac (equiv_intrel RS congruent2_commuteI) 1); +by (safe_tac intrel_cs); +by (rewtac split_def); +by (simp_tac (arith_ss addsimps add_ac@mult_ac) 1); +by (asm_simp_tac (arith_ss addsimps add_ac@mult_ac) 1); +by (rtac (intrelI RS(equiv_intrel RS equiv_class_eq)) 1); +by (rtac (zmult_congruent_lemma RS trans) 1); +by (rtac (zmult_congruent_lemma RS trans RS sym) 1); +by (rtac (zmult_congruent_lemma RS trans RS sym) 1); +by (rtac (zmult_congruent_lemma RS trans RS sym) 1); +by (asm_simp_tac (HOL_ss addsimps [add_mult_distrib RS sym]) 1); +by (asm_simp_tac (arith_ss addsimps add_ac@mult_ac) 1); +qed "zmult_congruent2"; + +(*Resolve th against the corresponding facts for zmult*) +val zmult_ize = RSLIST [equiv_intrel, zmult_congruent2]; + +goalw Integ.thy [zmult_def] + "Abs_Integ((intrel^^{})) * Abs_Integ((intrel^^{})) = \ +\ Abs_Integ(intrel ^^ {})"; +by (simp_tac (intrel_ss addsimps [zmult_ize UN_equiv_class2]) 1); +qed "zmult"; + +goalw Integ.thy [znat_def] "$#0 * z = $#0"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (asm_simp_tac (arith_ss addsimps [zmult]) 1); +qed "zmult_0"; + +goalw Integ.thy [znat_def] "$#Suc(0) * z = z"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (asm_simp_tac (arith_ss addsimps [zmult, add_0_right]) 1); +qed "zmult_1"; + +goal Integ.thy "($~ z) * w = $~ (z * w)"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (asm_simp_tac (intrel_ss addsimps ([zminus, zmult] @ add_ac)) 1); +qed "zmult_zminus"; + + +goal Integ.thy "($~ z) * ($~ w) = (z * w)"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (asm_simp_tac (intrel_ss addsimps ([zminus, zmult] @ add_ac)) 1); +qed "zmult_zminus_zminus"; + +goal Integ.thy "(z::int) * w = w * z"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (asm_simp_tac (intrel_ss addsimps ([zmult] @ add_ac @ mult_ac)) 1); +qed "zmult_commute"; + +goal Integ.thy "z * $# 0 = $#0"; +by (rtac ([zmult_commute, zmult_0] MRS trans) 1); +qed "zmult_0_right"; + +goal Integ.thy "z * $#Suc(0) = z"; +by (rtac ([zmult_commute, zmult_1] MRS trans) 1); +qed "zmult_1_right"; + +goal Integ.thy "((z1::int) * z2) * z3 = z1 * (z2 * z3)"; +by (res_inst_tac [("z","z1")] eq_Abs_Integ 1); +by (res_inst_tac [("z","z2")] eq_Abs_Integ 1); +by (res_inst_tac [("z","z3")] eq_Abs_Integ 1); +by (asm_simp_tac (intrel_ss addsimps ([zmult] @ add_ac @ mult_ac)) 1); +qed "zmult_assoc"; + +(*For AC rewriting*) +qed_goal "zmult_left_commute" Integ.thy + "(z1::int)*(z2*z3) = z2*(z1*z3)" + (fn _ => [rtac (zmult_commute RS trans) 1, rtac (zmult_assoc RS trans) 1, + rtac (zmult_commute RS arg_cong) 1]); + +(*Integer multiplication is an AC operator*) +val zmult_ac = [zmult_assoc, zmult_commute, zmult_left_commute]; + +goal Integ.thy "((z1::int) + z2) * w = (z1 * w) + (z2 * w)"; +by (res_inst_tac [("z","z1")] eq_Abs_Integ 1); +by (res_inst_tac [("z","z2")] eq_Abs_Integ 1); +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (asm_simp_tac + (intrel_ss addsimps ([zadd, zmult, add_mult_distrib] @ + add_ac @ mult_ac)) 1); +qed "zadd_zmult_distrib"; + +val zmult_commute'= read_instantiate [("z","w")] zmult_commute; + +goal Integ.thy "w * ($~ z) = $~ (w * z)"; +by (simp_tac (HOL_ss addsimps [zmult_commute', zmult_zminus]) 1); +qed "zmult_zminus_right"; + +goal Integ.thy "(w::int) * (z1 + z2) = (w * z1) + (w * z2)"; +by (simp_tac (HOL_ss addsimps [zmult_commute',zadd_zmult_distrib]) 1); +qed "zadd_zmult_distrib2"; + +val zadd_simps = + [zadd_0, zadd_0_right, zadd_zminus_inverse, zadd_zminus_inverse2]; + +val zminus_simps = [zminus_zminus, zminus_0, zminus_zadd_distrib]; + +val zmult_simps = [zmult_0, zmult_1, zmult_0_right, zmult_1_right, + zmult_zminus, zmult_zminus_right]; + +val integ_ss = + arith_ss addsimps (zadd_simps @ zminus_simps @ zmult_simps @ + [zmagnitude_znat, zmagnitude_zminus_znat]); + + +(**** Additional Theorems (by Mattolini; proofs mainly by lcp) ****) + +(* Some Theorems about zsuc and zpred *) +goalw Integ.thy [zsuc_def] "$#(Suc(n)) = zsuc($# n)"; +by (simp_tac (arith_ss addsimps [znat_add RS sym]) 1); +qed "znat_Suc"; + +goalw Integ.thy [zpred_def,zsuc_def,zdiff_def] "$~ zsuc(z) = zpred($~ z)"; +by (simp_tac integ_ss 1); +qed "zminus_zsuc"; + +goalw Integ.thy [zpred_def,zsuc_def,zdiff_def] "$~ zpred(z) = zsuc($~ z)"; +by (simp_tac integ_ss 1); +qed "zminus_zpred"; + +goalw Integ.thy [zsuc_def,zpred_def,zdiff_def] + "zpred(zsuc(z)) = z"; +by (simp_tac (integ_ss addsimps [zadd_assoc]) 1); +qed "zpred_zsuc"; + +goalw Integ.thy [zsuc_def,zpred_def,zdiff_def] + "zsuc(zpred(z)) = z"; +by (simp_tac (integ_ss addsimps [zadd_assoc]) 1); +qed "zsuc_zpred"; + +goal Integ.thy "(zpred(z)=w) = (z=zsuc(w))"; +by (safe_tac HOL_cs); +by (rtac (zsuc_zpred RS sym) 1); +by (rtac zpred_zsuc 1); +qed "zpred_to_zsuc"; + +goal Integ.thy "(zsuc(z)=w)=(z=zpred(w))"; +by (safe_tac HOL_cs); +by (rtac (zpred_zsuc RS sym) 1); +by (rtac zsuc_zpred 1); +qed "zsuc_to_zpred"; + +goal Integ.thy "($~ z = w) = (z = $~ w)"; +by (safe_tac HOL_cs); +by (rtac (zminus_zminus RS sym) 1); +by (rtac zminus_zminus 1); +qed "zminus_exchange"; + +goal Integ.thy"(zsuc(z)=zsuc(w)) = (z=w)"; +by (safe_tac intrel_cs); +by (dres_inst_tac [("f","zpred")] arg_cong 1); +by (asm_full_simp_tac (HOL_ss addsimps [zpred_zsuc]) 1); +qed "bijective_zsuc"; + +goal Integ.thy"(zpred(z)=zpred(w)) = (z=w)"; +by (safe_tac intrel_cs); +by (dres_inst_tac [("f","zsuc")] arg_cong 1); +by (asm_full_simp_tac (HOL_ss addsimps [zsuc_zpred]) 1); +qed "bijective_zpred"; + +(* Additional Theorems about zadd *) + +goalw Integ.thy [zsuc_def] "zsuc(z) + w = zsuc(z+w)"; +by (simp_tac (arith_ss addsimps zadd_ac) 1); +qed "zadd_zsuc"; + +goalw Integ.thy [zsuc_def] "w + zsuc(z) = zsuc(w+z)"; +by (simp_tac (arith_ss addsimps zadd_ac) 1); +qed "zadd_zsuc_right"; + +goalw Integ.thy [zpred_def,zdiff_def] "zpred(z) + w = zpred(z+w)"; +by (simp_tac (arith_ss addsimps zadd_ac) 1); +qed "zadd_zpred"; + +goalw Integ.thy [zpred_def,zdiff_def] "w + zpred(z) = zpred(w+z)"; +by (simp_tac (arith_ss addsimps zadd_ac) 1); +qed "zadd_zpred_right"; + + +(* Additional Theorems about zmult *) + +goalw Integ.thy [zsuc_def] "zsuc(w) * z = z + w * z"; +by (simp_tac (integ_ss addsimps [zadd_zmult_distrib, zadd_commute]) 1); +qed "zmult_zsuc"; + +goalw Integ.thy [zsuc_def] "z * zsuc(w) = z + w * z"; +by (simp_tac + (integ_ss addsimps [zadd_zmult_distrib2, zadd_commute, zmult_commute]) 1); +qed "zmult_zsuc_right"; + +goalw Integ.thy [zpred_def, zdiff_def] "zpred(w) * z = w * z - z"; +by (simp_tac (integ_ss addsimps [zadd_zmult_distrib]) 1); +qed "zmult_zpred"; + +goalw Integ.thy [zpred_def, zdiff_def] "z * zpred(w) = w * z - z"; +by (simp_tac (integ_ss addsimps [zadd_zmult_distrib2, zmult_commute]) 1); +qed "zmult_zpred_right"; + +(* Further Theorems about zsuc and zpred *) +goal Integ.thy "$#Suc(m) ~= $#0"; +by (simp_tac (integ_ss addsimps [inj_znat RS inj_eq]) 1); +qed "znat_Suc_not_znat_Zero"; + +bind_thm ("znat_Zero_not_znat_Suc", (znat_Suc_not_znat_Zero RS not_sym)); + + +goalw Integ.thy [zsuc_def,znat_def] "w ~= zsuc(w)"; +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (asm_full_simp_tac (intrel_ss addsimps [zadd]) 1); +qed "n_not_zsuc_n"; + +val zsuc_n_not_n = n_not_zsuc_n RS not_sym; + +goal Integ.thy "w ~= zpred(w)"; +by (safe_tac HOL_cs); +by (dres_inst_tac [("x","w"),("f","zsuc")] arg_cong 1); +by (asm_full_simp_tac (HOL_ss addsimps [zsuc_zpred,zsuc_n_not_n]) 1); +qed "n_not_zpred_n"; + +val zpred_n_not_n = n_not_zpred_n RS not_sym; + + +(* Theorems about less and less_equal *) + +goalw Integ.thy [zless_def, znegative_def, zdiff_def, znat_def] + "!!w. w ? n. z = w + $#(Suc(n))"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (res_inst_tac [("z","w")] eq_Abs_Integ 1); +by (safe_tac intrel_cs); +by (asm_full_simp_tac (intrel_ss addsimps [zadd, zminus]) 1); +by (safe_tac (intrel_cs addSDs [less_eq_Suc_add])); +by (res_inst_tac [("x","k")] exI 1); +by (asm_full_simp_tac (HOL_ss addsimps ([add_Suc RS sym] @ add_ac)) 1); +(*To cancel x2, rename it to be first!*) +by (rename_tac "a b c" 1); +by (asm_full_simp_tac (HOL_ss addsimps (add_left_cancel::add_ac)) 1); +qed "zless_eq_zadd_Suc"; + +goalw Integ.thy [zless_def, znegative_def, zdiff_def, znat_def] + "z < z + $#(Suc(n))"; +by (res_inst_tac [("z","z")] eq_Abs_Integ 1); +by (safe_tac intrel_cs); +by (simp_tac (intrel_ss addsimps [zadd, zminus]) 1); +by (REPEAT_SOME (ares_tac [refl, exI, singletonI, ImageI, conjI, intrelI])); +by (rtac le_less_trans 1); +by (rtac lessI 2); +by (asm_simp_tac (arith_ss addsimps ([le_add1,add_left_cancel_le]@add_ac)) 1); +qed "zless_zadd_Suc"; + +goal Integ.thy "!!z1 z2 z3. [| z1 z1 < (z3::int)"; +by (safe_tac (HOL_cs addSDs [zless_eq_zadd_Suc])); +by (simp_tac + (arith_ss addsimps [zadd_assoc, zless_zadd_Suc, znat_add RS sym]) 1); +qed "zless_trans"; + +goalw Integ.thy [zsuc_def] "z ~w R *) +bind_thm ("zless_asym", (zless_not_sym RS notE)); + +goal Integ.thy "!!z::int. ~ z R *) +bind_thm ("zless_anti_refl", (zless_not_refl RS notE)); + +goal Integ.thy "!!w. z w ~= (z::int)"; +by(fast_tac (HOL_cs addEs [zless_anti_refl]) 1); +qed "zless_not_refl2"; + + +(*"Less than" is a linear ordering*) +goalw Integ.thy [zless_def, znegative_def, zdiff_def] + "z z<=(w::int)"; +by (assume_tac 1); +qed "zleI"; + +goalw Integ.thy [zle_def] "!!w. z<=w ==> ~(w<(z::int))"; +by (assume_tac 1); +qed "zleD"; + +val zleE = make_elim zleD; + +goalw Integ.thy [zle_def] "!!z. ~ z <= w ==> w<(z::int)"; +by (fast_tac HOL_cs 1); +qed "not_zleE"; + +goalw Integ.thy [zle_def] "!!z. z < w ==> z <= (w::int)"; +by (fast_tac (HOL_cs addEs [zless_asym]) 1); +qed "zless_imp_zle"; + +goalw Integ.thy [zle_def] "!!z. z <= w ==> z < w | z=(w::int)"; +by (cut_facts_tac [zless_linear] 1); +by (fast_tac (HOL_cs addEs [zless_anti_refl,zless_asym]) 1); +qed "zle_imp_zless_or_eq"; + +goalw Integ.thy [zle_def] "!!z. z z <=(w::int)"; +by (cut_facts_tac [zless_linear] 1); +by (fast_tac (HOL_cs addEs [zless_anti_refl,zless_asym]) 1); +qed "zless_or_eq_imp_zle"; + +goal Integ.thy "(x <= (y::int)) = (x < y | x=y)"; +by (REPEAT(ares_tac [iffI, zless_or_eq_imp_zle, zle_imp_zless_or_eq] 1)); +qed "zle_eq_zless_or_eq"; + +goal Integ.thy "w <= (w::int)"; +by (simp_tac (HOL_ss addsimps [zle_eq_zless_or_eq]) 1); +qed "zle_refl"; + +val prems = goal Integ.thy "!!i. [| i <= j; j < k |] ==> i < (k::int)"; +by (dtac zle_imp_zless_or_eq 1); +by (fast_tac (HOL_cs addIs [zless_trans]) 1); +qed "zle_zless_trans"; + +goal Integ.thy "!!i. [| i <= j; j <= k |] ==> i <= (k::int)"; +by (EVERY1 [dtac zle_imp_zless_or_eq, dtac zle_imp_zless_or_eq, + rtac zless_or_eq_imp_zle, fast_tac (HOL_cs addIs [zless_trans])]); +qed "zle_trans"; + +goal Integ.thy "!!z. [| z <= w; w <= z |] ==> z = (w::int)"; +by (EVERY1 [dtac zle_imp_zless_or_eq, dtac zle_imp_zless_or_eq, + fast_tac (HOL_cs addEs [zless_anti_refl,zless_asym])]); +qed "zle_anti_sym"; + + +goal Integ.thy "!!w w' z::int. z + w' = z + w ==> w' = w"; +by (dres_inst_tac [("f", "%x. x + $~z")] arg_cong 1); +by (asm_full_simp_tac (integ_ss addsimps zadd_ac) 1); +qed "zadd_left_cancel"; + + +(*** Monotonicity results ***) + +goal Integ.thy "!!v w z::int. v < w ==> v + z < w + z"; +by (safe_tac (HOL_cs addSDs [zless_eq_zadd_Suc])); +by (simp_tac (HOL_ss addsimps zadd_ac) 1); +by (simp_tac (HOL_ss addsimps [zadd_assoc RS sym, zless_zadd_Suc]) 1); +qed "zadd_zless_mono1"; + +goal Integ.thy "!!v w z::int. (v+z < w+z) = (v < w)"; +by (safe_tac (HOL_cs addSEs [zadd_zless_mono1])); +by (dres_inst_tac [("z", "$~z")] zadd_zless_mono1 1); +by (asm_full_simp_tac (integ_ss addsimps [zadd_assoc]) 1); +qed "zadd_left_cancel_zless"; + +goal Integ.thy "!!v w z::int. (v+z <= w+z) = (v <= w)"; +by (asm_full_simp_tac + (integ_ss addsimps [zle_def, zadd_left_cancel_zless]) 1); +qed "zadd_left_cancel_zle"; + +(*"v<=w ==> v+z <= w+z"*) +bind_thm ("zadd_zle_mono1", zadd_left_cancel_zle RS iffD2); + + +goal Integ.thy "!!z' z::int. [| w'<=w; z'<=z |] ==> w' + z' <= w + z"; +by (etac (zadd_zle_mono1 RS zle_trans) 1); +by (simp_tac (HOL_ss addsimps [zadd_commute]) 1); +(*w moves to the end because it is free while z', z are bound*) +by (etac zadd_zle_mono1 1); +qed "zadd_zle_mono"; + +goal Integ.thy "!!w z::int. z<=$#0 ==> w+z <= w"; +by (dres_inst_tac [("z", "w")] zadd_zle_mono1 1); +by (asm_full_simp_tac (integ_ss addsimps [zadd_commute]) 1); +qed "zadd_zle_self";