src/HOL/Import/HOLLightInt.thy
changeset 43785 2bd54d4b5f3d
child 44766 d4d33a4d7548
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Import/HOLLightInt.thy	Wed Jul 13 00:23:24 2011 +0900
@@ -0,0 +1,207 @@
+(*  Title:      HOL/Import/HOLLightInt.thy
+    Author:     Cezary Kaliszyk
+*)
+
+header {* Compatibility theorems for HOL Light integers *}
+
+theory HOLLightInt imports Main Real GCD begin
+
+fun int_coprime where "int_coprime ((a :: int), (b :: int)) = coprime a b"
+
+lemma DEF_int_coprime:
+  "int_coprime = (\<lambda>u. \<exists>x y. ((fst u) * x) + ((snd u) * y) = int 1)"
+  apply (auto simp add: fun_eq_iff)
+  apply (metis bezout_int zmult_commute)
+  by (metis coprime_divisors_nat dvd_triv_left gcd_1_int gcd_add2_int)
+
+lemma INT_FORALL_POS:
+  "(\<forall>n. P (int n)) = (\<forall>i\<ge>(int 0). P i)"
+  by (auto, drule_tac x="nat i" in spec) simp
+
+lemma INT_LT_DISCRETE:
+  "(x < y) = (x + int 1 \<le> y)"
+  by auto
+
+lemma INT_ABS_MUL_1:
+  "(abs (x * y) = int 1) = (abs x = int 1 \<and> abs y = int 1)"
+  by simp (metis dvd_mult_right zdvd1_eq abs_zmult_eq_1 abs_mult zmult_1_right)
+
+lemma dest_int_rep:
+  "\<exists>(n :: nat). real (i :: int) = real n \<or> real i = - real n"
+  by (metis (full_types) of_int_of_nat real_eq_of_int real_of_nat_def)
+
+lemma DEF_int_add:
+  "op + = (\<lambda>u ua. floor (real u + real ua))"
+  by simp
+
+lemma DEF_int_sub:
+  "op - = (\<lambda>u ua. floor (real u - real ua))"
+  by simp
+
+lemma DEF_int_mul:
+  "op * = (\<lambda>u ua. floor (real u * real ua))"
+  by (metis floor_number_of number_of_is_id number_of_real_def real_eq_of_int real_of_int_mult)
+
+lemma DEF_int_abs:
+  "abs = (\<lambda>u. floor (abs (real u)))"
+  by (metis floor_real_of_int real_of_int_abs)
+
+lemma DEF_int_sgn:
+  "sgn = (\<lambda>u. floor (sgn (real u)))"
+  by (simp add: sgn_if fun_eq_iff)
+
+lemma int_sgn_th:
+  "real (sgn (x :: int)) = sgn (real x)"
+  by (simp add: sgn_if)
+
+lemma DEF_int_max:
+  "max = (\<lambda>u ua. floor (max (real u) (real ua)))"
+  by (metis floor_real_of_int real_of_int_le_iff sup_absorb1 sup_commute sup_max zle_linear)
+
+lemma int_max_th:
+  "real (max (x :: int) y) = max (real x) (real y)"
+  by (metis min_max.le_iff_sup min_max.sup_absorb1 real_of_int_le_iff zle_linear)
+
+lemma DEF_int_min:
+  "min = (\<lambda>u ua. floor (min (real u) (real ua)))"
+  by (metis floor_real_of_int inf_absorb1 inf_absorb2 inf_int_def inf_real_def real_of_int_le_iff zle_linear)
+
+lemma int_min_th:
+  "real (min (x :: int) y) = min (real x) (real y)"
+  by (metis inf_absorb1 inf_absorb2 inf_int_def inf_real_def real_of_int_le_iff zle_linear)
+
+lemma INT_IMAGE:
+  "(\<exists>n. x = int n) \<or> (\<exists>n. x = - int n)"
+  by (metis number_of_eq number_of_is_id of_int_of_nat)
+
+lemma DEF_int_pow:
+  "op ^ = (\<lambda>u ua. floor (real u ^ ua))"
+  by (simp add: floor_power)
+
+lemma DEF_int_divides:
+  "op dvd = (\<lambda>(u :: int) ua. \<exists>x. ua = u * x)"
+  by (metis dvdE dvdI)
+
+lemma DEF_int_divides':
+  "(a :: int) dvd b = (\<exists>x. b = a * x)"
+  by (metis dvdE dvdI)
+
+definition "int_mod (u :: int) ua ub = (u dvd (ua - ub))"
+
+lemma int_mod_def':
+  "int_mod = (\<lambda>u ua ub. (u dvd (ua - ub)))"
+  by (simp add: int_mod_def_raw)
+
+lemma int_congruent:
+  "\<forall>x xa xb. int_mod xb x xa = (\<exists>d. x - xa = xb * d)"
+  unfolding int_mod_def'
+  by (auto simp add: DEF_int_divides')
+
+lemma int_congruent':
+  "\<forall>(x :: int) y n. (n dvd x - y) = (\<exists>d. x - y = n * d)"
+  using int_congruent[unfolded int_mod_def] .
+
+fun int_gcd where
+  "int_gcd ((a :: int), (b :: int)) = gcd a b"
+
+definition "hl_mod (k\<Colon>int) (l\<Colon>int) = (if 0 \<le> l then k mod l else k mod - l)"
+
+lemma hl_mod_nonneg:
+  "b \<noteq> 0 \<Longrightarrow> hl_mod a b \<ge> 0"
+  by (simp add: hl_mod_def)
+
+lemma hl_mod_lt_abs:
+  "b \<noteq> 0 \<Longrightarrow> hl_mod a b < abs b"
+  by (simp add: hl_mod_def)
+
+definition "hl_div k l = (if 0 \<le> l then k div l else -(k div (-l)))"
+
+lemma hl_mod_div:
+  "n \<noteq> (0\<Colon>int) \<Longrightarrow> m = hl_div m n * n + hl_mod m n"
+  unfolding hl_div_def hl_mod_def
+  by auto (metis zmod_zdiv_equality zmult_commute zmult_zminus)
+
+lemma sth:
+  "(\<forall>(x :: int) y z. x + (y + z) = x + y + z) \<and>
+   (\<forall>(x :: int) y. x + y = y + x) \<and>
+   (\<forall>(x :: int). int 0 + x = x) \<and>
+   (\<forall>(x :: int) y z. x * (y * z) = x * y * z) \<and>
+   (\<forall>(x :: int) y. x * y = y * x) \<and>
+   (\<forall>(x :: int). int 1 * x = x) \<and>
+   (\<forall>(x :: int). int 0 * x = int 0) \<and>
+   (\<forall>(x :: int) y z. x * (y + z) = x * y + x * z) \<and>
+   (\<forall>(x :: int). x ^ 0 = int 1) \<and> (\<forall>(x :: int) n. x ^ Suc n = x * x ^ n)"
+  by (simp_all add: zadd_zmult_distrib2)
+
+lemma INT_DIVISION:
+  "n ~= int 0 \<Longrightarrow> m = hl_div m n * n + hl_mod m n \<and> int 0 \<le> hl_mod m n \<and> hl_mod m n < abs n"
+  by (auto simp add: hl_mod_nonneg hl_mod_lt_abs hl_mod_div)
+
+lemma INT_DIVMOD_EXIST_0:
+  "\<exists>q r. if n = int 0 then q = int 0 \<and> r = m
+         else int 0 \<le> r \<and> r < abs n \<and> m = q * n + r"
+  apply (rule_tac x="hl_div m n" in exI)
+  apply (rule_tac x="hl_mod m n" in exI)
+  apply (auto simp add: hl_mod_nonneg hl_mod_lt_abs hl_mod_div)
+  unfolding hl_div_def hl_mod_def
+  by auto
+
+lemma DEF_div:
+  "hl_div = (SOME q. \<exists>r. \<forall>m n. if n = int 0 then q m n = int 0 \<and> r m n = m
+     else (int 0) \<le> (r m n) \<and> (r m n) < (abs n) \<and> m = ((q m n) * n) + (r m n))"
+  apply (rule some_equality[symmetric])
+  apply (rule_tac x="hl_mod" in exI)
+  apply (auto simp add: fun_eq_iff hl_mod_nonneg hl_mod_lt_abs hl_mod_div)
+  apply (simp add: hl_div_def)
+  apply (simp add: hl_mod_def)
+  apply (drule_tac x="x" in spec)
+  apply (drule_tac x="xa" in spec)
+  apply (case_tac "0 = xa")
+  apply (simp add: hl_mod_def hl_div_def)
+  apply (case_tac "xa > 0")
+  apply (simp add: hl_mod_def hl_div_def)
+  apply (metis comm_semiring_1_class.normalizing_semiring_rules(24) div_mult_self2 not_less_iff_gr_or_eq order_less_le zadd_0 zdiv_eq_0_iff zmult_commute)
+  apply (simp add: hl_mod_def hl_div_def)
+  by (metis add.comm_neutral add_pos_nonneg div_mult_self1 less_minus_iff minus_add minus_add_cancel minus_minus mult_zero_right not_square_less_zero zdiv_eq_0_iff zdiv_zminus2)
+
+lemma DEF_rem:
+  "hl_mod = (SOME r. \<forall>m n. if n = int 0 then
+     (if 0 \<le> n then m div n else - (m div - n)) = int 0 \<and> r m n = m
+     else int 0 \<le> r m n \<and> r m n < abs n \<and>
+            m = (if 0 \<le> n then m div n else - (m div - n)) * n + r m n)"
+  apply (rule some_equality[symmetric])
+  apply (fold hl_div_def)
+  apply (auto simp add: fun_eq_iff hl_mod_nonneg hl_mod_lt_abs hl_mod_div)
+  apply (simp add: hl_div_def)
+  apply (simp add: hl_mod_def)
+  apply (drule_tac x="x" in spec)
+  apply (drule_tac x="xa" in spec)
+  apply (case_tac "0 = xa")
+  apply (simp add: hl_mod_def hl_div_def)
+  apply (case_tac "xa > 0")
+  apply (simp add: hl_mod_def hl_div_def)
+  apply (metis add_left_cancel mod_div_equality)
+  apply (simp add: hl_mod_def hl_div_def)
+  by (metis minus_mult_right mod_mult_self2 mod_pos_pos_trivial zadd_commute zminus_zmod zmod_zminus2 zmult_commute)
+
+lemma DEF_int_gcd:
+  "int_gcd = (SOME d. \<forall>a b. (int 0) \<le> (d (a, b)) \<and> (d (a, b)) dvd a \<and>
+       (d (a, b)) dvd b \<and> (\<exists>x y. d (a, b) = (a * x) + (b * y)))"
+  apply (rule some_equality[symmetric])
+  apply auto
+  apply (metis bezout_int zmult_commute)
+  apply (auto simp add: fun_eq_iff)
+  apply (drule_tac x="a" in spec)
+  apply (drule_tac x="b" in spec)
+  using gcd_greatest_int zdvd_antisym_nonneg
+  by auto
+
+definition "eqeq x y (r :: 'a \<Rightarrow> 'b \<Rightarrow> bool) = r x y"
+
+lemma INT_INTEGRAL:
+  "(\<forall>x. int 0 * x = int 0) \<and>
+   (\<forall>(x :: int) y z. (x + y = x + z) = (y = z)) \<and>
+   (\<forall>(w :: int) x y z. (w * y + x * z = w * z + x * y) = (w = x \<or> y = z))"
+  by (auto simp add: crossproduct_eq)
+
+end