(* Title: HOL/Metis_Examples/Clausify.thy
Author: Jasmin Blanchette, TU Muenchen
Testing Metis's clausifier.
*)
theory Clausify
imports Complex_Main
begin
text {* Definitional CNF for goal *}
(* FIXME: shouldn't need this *)
declare [[unify_search_bound = 100]]
declare [[unify_trace_bound = 100]]
axiomatization p :: "nat \<Rightarrow> nat \<Rightarrow> bool" where
pax: "\<exists>b. \<forall>a. ((p b a \<and> p 0 0 \<and> p 1 a) \<or> (p 0 1 \<and> p 1 0 \<and> p a b))"
declare [[metis_new_skolemizer = false]]
lemma "\<exists>b. \<forall>a. \<exists>x. (p b a \<or> x) \<and> (p 0 0 \<or> x) \<and> (p 1 a \<or> x) \<and>
(p 0 1 \<or> \<not> x) \<and> (p 1 0 \<or> \<not> x) \<and> (p a b \<or> \<not> x)"
by (metis pax)
lemma "\<exists>b. \<forall>a. \<exists>x. (p b a \<or> x) \<and> (p 0 0 \<or> x) \<and> (p 1 a \<or> x) \<and>
(p 0 1 \<or> \<not> x) \<and> (p 1 0 \<or> \<not> x) \<and> (p a b \<or> \<not> x)"
by (metisFT pax)
declare [[metis_new_skolemizer]]
lemma "\<exists>b. \<forall>a. \<exists>x. (p b a \<or> x) \<and> (p 0 0 \<or> x) \<and> (p 1 a \<or> x) \<and>
(p 0 1 \<or> \<not> x) \<and> (p 1 0 \<or> \<not> x) \<and> (p a b \<or> \<not> x)"
by (metis pax)
lemma "\<exists>b. \<forall>a. \<exists>x. (p b a \<or> x) \<and> (p 0 0 \<or> x) \<and> (p 1 a \<or> x) \<and>
(p 0 1 \<or> \<not> x) \<and> (p 1 0 \<or> \<not> x) \<and> (p a b \<or> \<not> x)"
by (metisFT pax)
text {* New Skolemizer *}
declare [[metis_new_skolemizer]]
lemma
fixes x :: real
assumes fn_le: "!!n. f n \<le> x" and 1: "f ----> lim f"
shows "lim f \<le> x"
by (metis 1 LIMSEQ_le_const2 fn_le)
definition
bounded :: "'a::metric_space set \<Rightarrow> bool" where
"bounded S \<longleftrightarrow> (\<exists>x eee. \<forall>y\<in>S. dist x y \<le> eee)"
lemma "bounded T \<Longrightarrow> S \<subseteq> T ==> bounded S"
by (metis bounded_def subset_eq)
lemma
assumes a: "Quotient R Abs Rep"
shows "symp R"
using a unfolding Quotient_def using sympI
by metisFT
lemma
"(\<exists>x \<in> set xs. P x) \<longleftrightarrow>
(\<exists>ys x zs. xs = ys @ x # zs \<and> P x \<and> (\<forall>z \<in> set zs. \<not> P z))"
by (metis split_list_last_prop [where P = P] in_set_conv_decomp)
lemma ex_tl: "EX ys. tl ys = xs"
using tl.simps(2) by fast
lemma "(\<exists>ys\<Colon>nat list. tl ys = xs) \<and> (\<exists>bs\<Colon>int list. tl bs = as)"
by (metis ex_tl)
end