From 417a4ed168b8982f7f8db417e2deb23693beedc7 Mon Sep 17 00:00:00 2001 From: David Aspinall Date: Tue, 3 Aug 2010 12:48:09 +0000 Subject: Move distribution examples into subdir --- isar/ex/KnasterTarski.thy | 115 ++++++ isar/ex/README | 7 + isar/ex/Sqrt.thy | 90 +++++ isar/ex/Sqrt_Script.thy | 70 ++++ isar/ex/Tarski.thy | 928 ++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 1210 insertions(+) create mode 100644 isar/ex/KnasterTarski.thy create mode 100644 isar/ex/README create mode 100644 isar/ex/Sqrt.thy create mode 100644 isar/ex/Sqrt_Script.thy create mode 100644 isar/ex/Tarski.thy diff --git a/isar/ex/KnasterTarski.thy b/isar/ex/KnasterTarski.thy new file mode 100644 index 00000000..a0adf653 --- /dev/null +++ b/isar/ex/KnasterTarski.thy @@ -0,0 +1,115 @@ +(********** + This file is copied from Isabelle2009-2. + **********) + +(* Title: HOL/Isar_examples/KnasterTarski.thy + Author: Markus Wenzel, TU Muenchen + +Typical textbook proof example. +*) + +header {* Textbook-style reasoning: the Knaster-Tarski Theorem *} + +theory KnasterTarski +imports Main Lattice_Syntax +begin + + +subsection {* Prose version *} + +text {* + According to the textbook \cite[pages 93--94]{davey-priestley}, the + Knaster-Tarski fixpoint theorem is as follows.\footnote{We have + dualized the argument, and tuned the notation a little bit.} + + \textbf{The Knaster-Tarski Fixpoint Theorem.} Let @{text L} be a + complete lattice and @{text "f: L \ L"} an order-preserving map. + Then @{text "\{x \ L | f(x) \ x}"} is a fixpoint of @{text f}. + + \textbf{Proof.} Let @{text "H = {x \ L | f(x) \ x}"} and @{text "a = + \H"}. For all @{text "x \ H"} we have @{text "a \ x"}, so @{text + "f(a) \ f(x) \ x"}. Thus @{text "f(a)"} is a lower bound of @{text + H}, whence @{text "f(a) \ a"}. We now use this inequality to prove + the reverse one (!) and thereby complete the proof that @{text a} is + a fixpoint. Since @{text f} is order-preserving, @{text "f(f(a)) \ + f(a)"}. This says @{text "f(a) \ H"}, so @{text "a \ f(a)"}. +*} + + +subsection {* Formal versions *} + +text {* + The Isar proof below closely follows the original presentation. + Virtually all of the prose narration has been rephrased in terms of + formal Isar language elements. Just as many textbook-style proofs, + there is a strong bias towards forward proof, and several bends in + the course of reasoning. +*} + +theorem Knaster_Tarski: + fixes f :: "'a::complete_lattice \ 'a" + assumes "mono f" + shows "\a. f a = a" +proof + let ?H = "{u. f u \ u}" + let ?a = "\?H" + show "f ?a = ?a" + proof - + { + fix x + assume "x \ ?H" + then have "?a \ x" by (rule Inf_lower) + with `mono f` have "f ?a \ f x" .. + also from `x \ ?H` have "\ \ x" .. + finally have "f ?a \ x" . + } + then have "f ?a \ ?a" by (rule Inf_greatest) + { + also presume "\ \ f ?a" + finally (order_antisym) show ?thesis . + } + from `mono f` and `f ?a \ ?a` have "f (f ?a) \ f ?a" .. + then have "f ?a \ ?H" .. + then show "?a \ f ?a" by (rule Inf_lower) + qed +qed + +text {* + Above we have used several advanced Isar language elements, such as + explicit block structure and weak assumptions. Thus we have + mimicked the particular way of reasoning of the original text. + + In the subsequent version the order of reasoning is changed to + achieve structured top-down decomposition of the problem at the + outer level, while only the inner steps of reasoning are done in a + forward manner. We are certainly more at ease here, requiring only + the most basic features of the Isar language. +*} + +theorem Knaster_Tarski': + fixes f :: "'a::complete_lattice \ 'a" + assumes "mono f" + shows "\a. f a = a" +proof + let ?H = "{u. f u \ u}" + let ?a = "\?H" + show "f ?a = ?a" + proof (rule order_antisym) + show "f ?a \ ?a" + proof (rule Inf_greatest) + fix x + assume "x \ ?H" + then have "?a \ x" by (rule Inf_lower) + with `mono f` have "f ?a \ f x" .. + also from `x \ ?H` have "\ \ x" .. + finally show "f ?a \ x" . + qed + show "?a \ f ?a" + proof (rule Inf_lower) + from `mono f` and `f ?a \ ?a` have "f (f ?a) \ f ?a" .. + then show "f ?a \ ?H" .. + qed + qed +qed + +end diff --git a/isar/ex/README b/isar/ex/README new file mode 100644 index 00000000..efa79fdb --- /dev/null +++ b/isar/ex/README @@ -0,0 +1,7 @@ +This directory contains some example files copied from Isabelle2009-2. + +These are re-distributed with Proof General for convenience of trying +out PG without needing a local installation of Isabelle. + +They can also be used as test cases. + diff --git a/isar/ex/Sqrt.thy b/isar/ex/Sqrt.thy new file mode 100644 index 00000000..96164f90 --- /dev/null +++ b/isar/ex/Sqrt.thy @@ -0,0 +1,90 @@ +(* Title: HOL/ex/Sqrt.thy + Author: Markus Wenzel, TU Muenchen +*) + +header {* Square roots of primes are irrational *} + +theory Sqrt +imports Complex_Main "~~/src/HOL/Number_Theory/Primes" +begin + +text {* + The square root of any prime number (including @{text 2}) is + irrational. +*} + +theorem sqrt_prime_irrational: + assumes "prime (p::nat)" + shows "sqrt (real p) \ \" +proof + from `prime p` have p: "1 < p" by (simp add: prime_nat_def) + assume "sqrt (real p) \ \" + then obtain m n :: nat where + n: "n \ 0" and sqrt_rat: "\sqrt (real p)\ = real m / real n" + and gcd: "gcd m n = 1" by (rule Rats_abs_nat_div_natE) + have eq: "m\ = p * n\" + proof - + from n and sqrt_rat have "real m = \sqrt (real p)\ * real n" by simp + then have "real (m\) = (sqrt (real p))\ * real (n\)" + by (auto simp add: power2_eq_square) + also have "(sqrt (real p))\ = real p" by simp + also have "\ * real (n\) = real (p * n\)" by simp + finally show ?thesis .. + qed + have "p dvd m \ p dvd n" + proof + from eq have "p dvd m\" .. + with `prime p` pos2 show "p dvd m" by (rule prime_dvd_power_nat) + then obtain k where "m = p * k" .. + with eq have "p * n\ = p\ * k\" by (auto simp add: power2_eq_square mult_ac) + with p have "n\ = p * k\" by (simp add: power2_eq_square) + then have "p dvd n\" .. + with `prime p` pos2 show "p dvd n" by (rule prime_dvd_power_nat) + qed + then have "p dvd gcd m n" .. + with gcd have "p dvd 1" by simp + then have "p \ 1" by (simp add: dvd_imp_le) + with p show False by simp +qed + +corollary "sqrt (real (2::nat)) \ \" + by (rule sqrt_prime_irrational) (rule two_is_prime_nat) + + +subsection {* Variations *} + +text {* + Here is an alternative version of the main proof, using mostly + linear forward-reasoning. While this results in less top-down + structure, it is probably closer to proofs seen in mathematics. +*} + +theorem + assumes "prime (p::nat)" + shows "sqrt (real p) \ \" +proof + from `prime p` have p: "1 < p" by (simp add: prime_nat_def) + assume "sqrt (real p) \ \" + then obtain m n :: nat where + n: "n \ 0" and sqrt_rat: "\sqrt (real p)\ = real m / real n" + and gcd: "gcd m n = 1" by (rule Rats_abs_nat_div_natE) + from n and sqrt_rat have "real m = \sqrt (real p)\ * real n" by simp + then have "real (m\) = (sqrt (real p))\ * real (n\)" + by (auto simp add: power2_eq_square) + also have "(sqrt (real p))\ = real p" by simp + also have "\ * real (n\) = real (p * n\)" by simp + finally have eq: "m\ = p * n\" .. + then have "p dvd m\" .. + with `prime p` pos2 have dvd_m: "p dvd m" by (rule prime_dvd_power_nat) + then obtain k where "m = p * k" .. + with eq have "p * n\ = p\ * k\" by (auto simp add: power2_eq_square mult_ac) + with p have "n\ = p * k\" by (simp add: power2_eq_square) + then have "p dvd n\" .. + with `prime p` pos2 have "p dvd n" by (rule prime_dvd_power_nat) + with dvd_m have "p dvd gcd m n" by (rule gcd_greatest_nat) + with gcd have "p dvd 1" by simp + then have "p \ 1" by (simp add: dvd_imp_le) + with p show False by simp +qed + +end diff --git a/isar/ex/Sqrt_Script.thy b/isar/ex/Sqrt_Script.thy new file mode 100644 index 00000000..08634ea7 --- /dev/null +++ b/isar/ex/Sqrt_Script.thy @@ -0,0 +1,70 @@ +(* Title: HOL/ex/Sqrt_Script.thy + Author: Lawrence C Paulson, Cambridge University Computer Laboratory + Copyright 2001 University of Cambridge +*) + +header {* Square roots of primes are irrational (script version) *} + +theory Sqrt_Script +imports Complex_Main "~~/src/HOL/Number_Theory/Primes" +begin + +text {* + \medskip Contrast this linear Isabelle/Isar script with Markus + Wenzel's more mathematical version. +*} + +subsection {* Preliminaries *} + +lemma prime_nonzero: "prime (p::nat) \ p \ 0" + by (force simp add: prime_nat_def) + +lemma prime_dvd_other_side: + "(n::nat) * n = p * (k * k) \ prime p \ p dvd n" + apply (subgoal_tac "p dvd n * n", blast dest: prime_dvd_mult_nat) + apply auto + done + +lemma reduction: "prime (p::nat) \ + 0 < k \ k * k = p * (j * j) \ k < p * j \ 0 < j" + apply (rule ccontr) + apply (simp add: linorder_not_less) + apply (erule disjE) + apply (frule mult_le_mono, assumption) + apply auto + apply (force simp add: prime_nat_def) + done + +lemma rearrange: "(j::nat) * (p * j) = k * k \ k * k = p * (j * j)" + by (simp add: mult_ac) + +lemma prime_not_square: + "prime (p::nat) \ (\k. 0 < k \ m * m \ p * (k * k))" + apply (induct m rule: nat_less_induct) + apply clarify + apply (frule prime_dvd_other_side, assumption) + apply (erule dvdE) + apply (simp add: nat_mult_eq_cancel_disj prime_nonzero) + apply (blast dest: rearrange reduction) + done + + +subsection {* Main theorem *} + +text {* + The square root of any prime number (including @{text 2}) is + irrational. +*} + +theorem prime_sqrt_irrational: + "prime (p::nat) \ x * x = real p \ 0 \ x \ x \ \" + apply (rule notI) + apply (erule Rats_abs_nat_div_natE) + apply (simp del: real_of_nat_mult + add: abs_if divide_eq_eq prime_not_square real_of_nat_mult [symmetric]) + done + +lemmas two_sqrt_irrational = + prime_sqrt_irrational [OF two_is_prime_nat] + +end diff --git a/isar/ex/Tarski.thy b/isar/ex/Tarski.thy new file mode 100644 index 00000000..9d4e8c0b --- /dev/null +++ b/isar/ex/Tarski.thy @@ -0,0 +1,928 @@ +(********** + This file is copied from Isabelle2009-2. + It has been beautified with Tokens \ Replace Shortcuts + **********) + +(* Title: HOL/ex/Tarski.thy + ID: $Id$ + Author: Florian Kammüller, Cambridge University Computer Laboratory +*) + +header {* The Full Theorem of Tarski *} + +theory Tarski +imports Main FuncSet +begin + +text {* + Minimal version of lattice theory plus the full theorem of Tarski: + The fixedpoints of a complete lattice themselves form a complete + lattice. + + Illustrates first-class theories, using the Sigma representation of + structures. Tidied and converted to Isar by lcp. +*} + +record 'a potype = + pset :: "'a set" + order :: "('a * 'a) set" + +definition + monotone :: "['a \ 'a, 'a set, ('a *'a)set] \ bool" where + "monotone f A r = (\x\A. \y\A. (x, y): r \ ((f x), (f y)) : r)" + +definition + least :: "['a \ bool, 'a potype] \ 'a" where + "least P po = (SOME x. x: pset po & P x & + (\y \ pset po. P y \ (x,y): order po))" + +definition + greatest :: "['a \ bool, 'a potype] \ 'a" where + "greatest P po = (SOME x. x: pset po & P x & + (\y \ pset po. P y \ (y,x): order po))" + +definition + lub :: "['a set, 'a potype] \ 'a" where + "lub S po = least (%x. \y\S. (y,x): order po) po" + +definition + glb :: "['a set, 'a potype] \ 'a" where + "glb S po = greatest (%x. \y\S. (x,y): order po) po" + +definition + isLub :: "['a set, 'a potype, 'a] \ bool" where + "isLub S po = (%L. (L: pset po & (\y\S. (y,L): order po) & + (\z\pset po. (\y\S. (y,z): order po) \ (L,z): order po)))" + +definition + isGlb :: "['a set, 'a potype, 'a] \ bool" where + "isGlb S po = (%G. (G: pset po & (\y\S. (G,y): order po) & + (\z \ pset po. (\y\S. (z,y): order po) \ (z,G): order po)))" + +definition + "fix" :: "[('a \ 'a), 'a set] \ 'a set" where + "fix f A = {x. x: A & f x = x}" + +definition + interval :: "[('a*'a) set,'a, 'a ] \ 'a set" where + "interval r a b = {x. (a,x): r & (x,b): r}" + + +definition + Bot :: "'a potype \ 'a" where + "Bot po = least (%x. True) po" + +definition + Top :: "'a potype \ 'a" where + "Top po = greatest (%x. True) po" + +definition + PartialOrder :: "('a potype) set" where + "PartialOrder = {P. refl_on (pset P) (order P) & antisym (order P) & + trans (order P)}" + +definition + CompleteLattice :: "('a potype) set" where + "CompleteLattice = {cl. cl: PartialOrder & + (\S. S \ pset cl \ (\L. isLub S cl L)) & + (\S. S \ pset cl \ (\G. isGlb S cl G))}" + +definition + CLF_set :: "('a potype * ('a \ 'a)) set" where + "CLF_set = (SIGMA cl: CompleteLattice. + {f. f: pset cl \ pset cl & monotone f (pset cl) (order cl)})" + +definition + induced :: "['a set, ('a * 'a) set] \ ('a *'a)set" where + "induced A r = {(a,b). a : A & b: A & (a,b): r}" + + +definition + sublattice :: "('a potype * 'a set)set" where + "sublattice = + (SIGMA cl: CompleteLattice. + {S. S \ pset cl & + \ pset = S, order = induced S (order cl) \: CompleteLattice})" + +abbreviation + sublat :: "['a set, 'a potype] \ bool" ("_ \= _" [51,50]50) where + "S \= cl \ S : sublattice `` {cl}" + +definition + dual :: "'a potype \ 'a potype" where + "dual po = \ pset = pset po, order = converse (order po) \" + +locale S = + fixes cl :: "'a potype" + and A :: "'a set" + and r :: "('a * 'a) set" + defines A_def: "A \ pset cl" + and r_def: "r \ order cl" + +locale PO = S + + assumes cl_po: "cl : PartialOrder" + +locale CL = S + + assumes cl_co: "cl : CompleteLattice" + +sublocale CL < PO +apply (simp_all add: A_def r_def) +apply unfold_locales +using cl_co unfolding CompleteLattice_def by auto + +locale CLF = S + + fixes f :: "'a \ 'a" + and P :: "'a set" + assumes f_cl: "(cl,f) : CLF_set" (*was the equivalent "f : CLF_set``{cl}"*) + defines P_def: "P \ fix f A" + +sublocale CLF < CL +apply (simp_all add: A_def r_def) +apply unfold_locales +using f_cl unfolding CLF_set_def by auto + +locale Tarski = CLF + + fixes Y :: "'a set" + and intY1 :: "'a set" + and v :: "'a" + assumes + Y_ss: "Y \ P" + defines + intY1_def: "intY1 \ interval r (lub Y cl) (Top cl)" + and v_def: "v \ glb {x. ((%x: intY1. f x) x, x): induced intY1 r & + x: intY1} + \ pset=intY1, order=induced intY1 r\" + + +subsection {* Partial Order *} + +lemma (in PO) dual: + "PO (dual cl)" +apply unfold_locales +using cl_po +unfolding PartialOrder_def dual_def +by auto + +lemma (in PO) PO_imp_refl_on [simp]: "refl_on A r" +apply (insert cl_po) +apply (simp add: PartialOrder_def A_def r_def) +done + +lemma (in PO) PO_imp_sym [simp]: "antisym r" +apply (insert cl_po) +apply (simp add: PartialOrder_def r_def) +done + +lemma (in PO) PO_imp_trans [simp]: "trans r" +apply (insert cl_po) +apply (simp add: PartialOrder_def r_def) +done + +lemma (in PO) reflE: "x \ A \ (x, x) \ r" +apply (insert cl_po) +apply (simp add: PartialOrder_def refl_on_def A_def r_def) +done + +lemma (in PO) antisymE: "\ (a, b) \ r; (b, a) \ r \ \ a = b" +apply (insert cl_po) +apply (simp add: PartialOrder_def antisym_def r_def) +done + +lemma (in PO) transE: "\ (a, b) \ r; (b, c) \ r\ \ (a,c) \ r" +apply (insert cl_po) +apply (simp add: PartialOrder_def r_def) +apply (unfold trans_def, fast) +done + +lemma (in PO) monotoneE: + "\ monotone f A r; x \ A; y \ A; (x, y) \ r \ \ (f x, f y) \ r" +by (simp add: monotone_def) + +lemma (in PO) po_subset_po: + "S \ A \ \ pset = S, order = induced S r \ \ PartialOrder" +apply (simp (no_asm) add: PartialOrder_def) +apply auto +-- {* refl *} +apply (simp add: refl_on_def induced_def) +apply (blast intro: reflE) +-- {* antisym *} +apply (simp add: antisym_def induced_def) +apply (blast intro: antisymE) +-- {* trans *} +apply (simp add: trans_def induced_def) +apply (blast intro: transE) +done + +lemma (in PO) indE: "\ (x, y) \ induced S r; S \ A \ \ (x, y) \ r" +by (simp add: add: induced_def) + +lemma (in PO) indI: "\ (x, y) \ r; x \ S; y \ S \ \ (x, y) \ induced S r" +by (simp add: add: induced_def) + +lemma (in CL) CL_imp_ex_isLub: "S \ A \ \L. isLub S cl L" +apply (insert cl_co) +apply (simp add: CompleteLattice_def A_def) +done + +declare (in CL) cl_co [simp] + +lemma isLub_lub: "(\L. isLub S cl L) = isLub S cl (lub S cl)" +by (simp add: lub_def least_def isLub_def some_eq_ex [symmetric]) + +lemma isGlb_glb: "(\G. isGlb S cl G) = isGlb S cl (glb S cl)" +by (simp add: glb_def greatest_def isGlb_def some_eq_ex [symmetric]) + +lemma isGlb_dual_isLub: "isGlb S cl = isLub S (dual cl)" +by (simp add: isLub_def isGlb_def dual_def converse_def) + +lemma isLub_dual_isGlb: "isLub S cl = isGlb S (dual cl)" +by (simp add: isLub_def isGlb_def dual_def converse_def) + +lemma (in PO) dualPO: "dual cl \ PartialOrder" +apply (insert cl_po) +apply (simp add: PartialOrder_def dual_def refl_on_converse + trans_converse antisym_converse) +done + +lemma Rdual: + "\S. (S \ A \( \L. isLub S \ pset = A, order = r\ L)) + \ \S. (S \ A \ (\G. isGlb S \ pset = A, order = r\ G))" +apply safe +apply (rule_tac x = "lub {y. y \ A & (\k \ S. (y, k) \ r)} + \pset = A, order = r\ " in exI) +apply (drule_tac x = "{y. y \ A & (\k \ S. (y,k) \ r) }" in spec) +apply (drule mp, fast) +apply (simp add: isLub_lub isGlb_def) +apply (simp add: isLub_def, blast) +done + +lemma lub_dual_glb: "lub S cl = glb S (dual cl)" +by (simp add: lub_def glb_def least_def greatest_def dual_def converse_def) + +lemma glb_dual_lub: "glb S cl = lub S (dual cl)" +by (simp add: lub_def glb_def least_def greatest_def dual_def converse_def) + +lemma CL_subset_PO: "CompleteLattice \ PartialOrder" +by (simp add: PartialOrder_def CompleteLattice_def, fast) + +lemmas CL_imp_PO = CL_subset_PO [THEN subsetD] + +(*declare CL_imp_PO [THEN PO.PO_imp_refl, simp] +declare CL_imp_PO [THEN PO.PO_imp_sym, simp] +declare CL_imp_PO [THEN PO.PO_imp_trans, simp]*) + +lemma (in CL) CO_refl_on: "refl_on A r" +by (rule PO_imp_refl_on) + +lemma (in CL) CO_antisym: "antisym r" +by (rule PO_imp_sym) + +lemma (in CL) CO_trans: "trans r" +by (rule PO_imp_trans) + +lemma CompleteLatticeI: + "\ po \ PartialOrder; (\S. S \ pset po \ (\L. isLub S po L)); + (\S. S \ pset po \ (\G. isGlb S po G))\ + \ po \ CompleteLattice" +apply (unfold CompleteLattice_def, blast) +done + +lemma (in CL) CL_dualCL: "dual cl \ CompleteLattice" +apply (insert cl_co) +apply (simp add: CompleteLattice_def dual_def) +apply (fold dual_def) +apply (simp add: isLub_dual_isGlb [symmetric] isGlb_dual_isLub [symmetric] + dualPO) +done + +lemma (in PO) dualA_iff: "pset (dual cl) = pset cl" +by (simp add: dual_def) + +lemma (in PO) dualr_iff: "((x, y) \ (order(dual cl))) = ((y, x) \ order cl)" +by (simp add: dual_def) + +lemma (in PO) monotone_dual: + "monotone f (pset cl) (order cl) + \ monotone f (pset (dual cl)) (order(dual cl))" +by (simp add: monotone_def dualA_iff dualr_iff) + +lemma (in PO) interval_dual: + "\ x \ A; y \ A\ \ interval r x y = interval (order(dual cl)) y x" +apply (simp add: interval_def dualr_iff) +apply (fold r_def, fast) +done + +lemma (in PO) trans: + "(x, y) \ r \ (y, z) \ r \ (x, z) \ r" +using cl_po apply (auto simp add: PartialOrder_def r_def) +unfolding trans_def by blast + +lemma (in PO) interval_not_empty: + "interval r a b \ {} \ (a, b) \ r" +apply (simp add: interval_def) +using trans by blast + +lemma (in PO) interval_imp_mem: "x \ interval r a b \ (a, x) \ r" +by (simp add: interval_def) + +lemma (in PO) left_in_interval: + "\ a \ A; b \ A; interval r a b \ {} \ \ a \ interval r a b" +apply (simp (no_asm_simp) add: interval_def) +apply (simp add: PO_imp_trans interval_not_empty) +apply (simp add: reflE) +done + +lemma (in PO) right_in_interval: + "\ a \ A; b \ A; interval r a b \ {} \ \ b \ interval r a b" +apply (simp (no_asm_simp) add: interval_def) +apply (simp add: PO_imp_trans interval_not_empty) +apply (simp add: reflE) +done + + +subsection {* sublattice *} + +lemma (in PO) sublattice_imp_CL: + "S \= cl \ \ pset = S, order = induced S r \ \ CompleteLattice" +by (simp add: sublattice_def CompleteLattice_def r_def) + +lemma (in CL) sublatticeI: + "\ S \ A; \ pset = S, order = induced S r \ \ CompleteLattice \ + \ S \= cl" +by (simp add: sublattice_def A_def r_def) + +lemma (in CL) dual: + "CL (dual cl)" +apply unfold_locales +using cl_co unfolding CompleteLattice_def +apply (simp add: dualPO isGlb_dual_isLub [symmetric] isLub_dual_isGlb [symmetric] dualA_iff) +done + + +subsection {* lub *} + +lemma (in CL) lub_unique: "\ S \ A; isLub S cl x; isLub S cl L\ \ x = L" +apply (rule antisymE) +apply (auto simp add: isLub_def r_def) +done + +lemma (in CL) lub_upper: "\S \ A; x \ S\ \ (x, lub S cl) \ r" +apply (rule CL_imp_ex_isLub [THEN exE], assumption) +apply (unfold lub_def least_def) +apply (rule some_equality [THEN ssubst]) + apply (simp add: isLub_def) + apply (simp add: lub_unique A_def isLub_def) +apply (simp add: isLub_def r_def) +done + +lemma (in CL) lub_least: + "\ S \ A; L \ A; \x \ S. (x,L) \ r \ \ (lub S cl, L) \ r" +apply (rule CL_imp_ex_isLub [THEN exE], assumption) +apply (unfold lub_def least_def) +apply (rule_tac s=x in some_equality [THEN ssubst]) + apply (simp add: isLub_def) + apply (simp add: lub_unique A_def isLub_def) +apply (simp add: isLub_def r_def A_def) +done + +lemma (in CL) lub_in_lattice: "S \ A \ lub S cl \ A" +apply (rule CL_imp_ex_isLub [THEN exE], assumption) +apply (unfold lub_def least_def) +apply (subst some_equality) +apply (simp add: isLub_def) +prefer 2 apply (simp add: isLub_def A_def) +apply (simp add: lub_unique A_def isLub_def) +done + +lemma (in CL) lubI: + "\ S \ A; L \ A; \x \ S. (x,L) \ r; + \z \ A. (\y \ S. (y,z) \ r) \ (L,z) \ r \ \ L = lub S cl" +apply (rule lub_unique, assumption) +apply (simp add: isLub_def A_def r_def) +apply (unfold isLub_def) +apply (rule conjI) +apply (fold A_def r_def) +apply (rule lub_in_lattice, assumption) +apply (simp add: lub_upper lub_least) +done + +lemma (in CL) lubIa: "\ S \ A; isLub S cl L \ \ L = lub S cl" +by (simp add: lubI isLub_def A_def r_def) + +lemma (in CL) isLub_in_lattice: "isLub S cl L \ L \ A" +by (simp add: isLub_def A_def) + +lemma (in CL) isLub_upper: "\isLub S cl L; y \ S\ \ (y, L) \ r" +by (simp add: isLub_def r_def) + +lemma (in CL) isLub_least: + "\ isLub S cl L; z \ A; \y \ S. (y, z) \ r\ \ (L, z) \ r" +by (simp add: isLub_def A_def r_def) + +lemma (in CL) isLubI: + "\ L \ A; \y \ S. (y, L) \ r; + (\z \ A. (\y \ S. (y, z):r) \ (L, z) \ r)\ \ isLub S cl L" +by (simp add: isLub_def A_def r_def) + + +subsection {* glb *} + +lemma (in CL) glb_in_lattice: "S \ A \ glb S cl \ A" +apply (subst glb_dual_lub) +apply (simp add: A_def) +apply (rule dualA_iff [THEN subst]) +apply (rule CL.lub_in_lattice) +apply (rule dual) +apply (simp add: dualA_iff) +done + +lemma (in CL) glb_lower: "\S \ A; x \ S\ \ (glb S cl, x) \ r" +apply (subst glb_dual_lub) +apply (simp add: r_def) +apply (rule dualr_iff [THEN subst]) +apply (rule CL.lub_upper) +apply (rule dual) +apply (simp add: dualA_iff A_def, assumption) +done + +text {* + Reduce the sublattice property by using substructural properties; + abandoned see @{text "Tarski_4.ML"}. +*} + +lemma (in CLF) [simp]: + "f: pset cl \ pset cl & monotone f (pset cl) (order cl)" +apply (insert f_cl) +apply (simp add: CLF_set_def) +done + +declare (in CLF) f_cl [simp] + + +lemma (in CLF) f_in_funcset: "f \ A \ A" +by (simp add: A_def) + +lemma (in CLF) monotone_f: "monotone f A r" +by (simp add: A_def r_def) + +lemma (in CLF) CLF_dual: "(dual cl, f) \ CLF_set" +apply (simp add: CLF_set_def CL_dualCL monotone_dual) +apply (simp add: dualA_iff) +done + +lemma (in CLF) dual: + "CLF (dual cl) f" +apply (rule CLF.intro) +apply (rule CLF_dual) +done + + +subsection {* fixed points *} + +lemma fix_subset: "fix f A \ A" +by (simp add: fix_def, fast) + +lemma fix_imp_eq: "x \ fix f A \ f x = x" +by (simp add: fix_def) + +lemma fixf_subset: + "\ A \ B; x \ fix (%y: A. f y) A \ \ x \ fix f B" +by (simp add: fix_def, auto) + + +subsection {* lemmas for Tarski, lub *} +lemma (in CLF) lubH_le_flubH: + "H = {x. (x, f x) \ r & x \ A} \ (lub H cl, f (lub H cl)) \ r" +apply (rule lub_least, fast) +apply (rule f_in_funcset [THEN funcset_mem]) +apply (rule lub_in_lattice, fast) +-- {* @{text "\x:H. (x, f (lub H r)) \ r"} *} +apply (rule ballI) +apply (rule transE) +-- {* instantiates @{text "(x, ???z) \ order cl to (x, f x)"}, *} +-- {* because of the def of @{text H} *} +apply fast +-- {* so it remains to show @{text "(f x, f (lub H cl)) \ r"} *} +apply (rule_tac f = "f" in monotoneE) +apply (rule monotone_f, fast) +apply (rule lub_in_lattice, fast) +apply (rule lub_upper, fast) +apply assumption +done + +lemma (in CLF) flubH_le_lubH: + "\ H = {x. (x, f x) \ r & x \ A} \ \ (f (lub H cl), lub H cl) \ r" +apply (rule lub_upper, fast) +apply (rule_tac t = "H" in ssubst, assumption) +apply (rule CollectI) +apply (rule conjI) +apply (rule_tac [2] f_in_funcset [THEN funcset_mem]) +apply (rule_tac [2] lub_in_lattice) +prefer 2 apply fast +apply (rule_tac f = "f" in monotoneE) +apply (rule monotone_f) + apply (blast intro: lub_in_lattice) + apply (blast intro: lub_in_lattice f_in_funcset [THEN funcset_mem]) +apply (simp add: lubH_le_flubH) +done + +lemma (in CLF) lubH_is_fixp: + "H = {x. (x, f x) \ r & x \ A} \ lub H cl \ fix f A" +apply (simp add: fix_def) +apply (rule conjI) +apply (rule lub_in_lattice, fast) +apply (rule antisymE) +apply (simp add: flubH_le_lubH) +apply (simp add: lubH_le_flubH) +done + +lemma (in CLF) fix_in_H: + "\ H = {x. (x, f x) \ r & x \ A}; x \ P \ \ x \ H" +by (simp add: P_def fix_imp_eq [of _ f A] reflE CO_refl_on + fix_subset [of f A, THEN subsetD]) + +lemma (in CLF) fixf_le_lubH: + "H = {x. (x, f x) \ r & x \ A} \ \x \ fix f A. (x, lub H cl) \ r" +apply (rule ballI) +apply (rule lub_upper, fast) +apply (rule fix_in_H) +apply (simp_all add: P_def) +done + +lemma (in CLF) lubH_least_fixf: + "H = {x. (x, f x) \ r & x \ A} + \ \L. (\y \ fix f A. (y,L) \ r) \ (lub H cl, L) \ r" +apply (rule allI) +apply (rule impI) +apply (erule bspec) +apply (rule lubH_is_fixp, assumption) +done + +subsection {* Tarski fixpoint theorem 1, first part *} +lemma (in CLF) T_thm_1_lub: "lub P cl = lub {x. (x, f x) \ r & x \ A} cl" +apply (rule sym) +apply (simp add: P_def) +apply (rule lubI) +apply (rule fix_subset) +apply (rule lub_in_lattice, fast) +apply (simp add: fixf_le_lubH) +apply (simp add: lubH_least_fixf) +done + +lemma (in CLF) glbH_is_fixp: "H = {x. (f x, x) \ r & x \ A} \ glb H cl \ P" + -- {* Tarski for glb *} +apply (simp add: glb_dual_lub P_def A_def r_def) +apply (rule dualA_iff [THEN subst]) +apply (rule CLF.lubH_is_fixp) +apply (rule dual) +apply (simp add: dualr_iff dualA_iff) +done + +lemma (in CLF) T_thm_1_glb: "glb P cl = glb {x. (f x, x) \ r & x \ A} cl" +apply (simp add: glb_dual_lub P_def A_def r_def) +apply (rule dualA_iff [THEN subst]) +apply (simp add: CLF.T_thm_1_lub [of _ f, OF dual] + dualPO CL_dualCL CLF_dual dualr_iff) +done + +subsection {* interval *} + +lemma (in CLF) rel_imp_elem: "(x, y) \ r \ x \ A" +apply (insert CO_refl_on) +apply (simp add: refl_on_def, blast) +done + +lemma (in CLF) interval_subset: "\ a \ A; b \ A \ \ interval r a b \ A" +apply (simp add: interval_def) +apply (blast intro: rel_imp_elem) +done + +lemma (in CLF) intervalI: + "\ (a, x) \ r; (x, b) \ r \ \ x \ interval r a b" +by (simp add: interval_def) + +lemma (in CLF) interval_lemma1: + "\ S \ interval r a b; x \ S \ \ (a, x) \ r" +by (unfold interval_def, fast) + +lemma (in CLF) interval_lemma2: + "\ S \ interval r a b; x \ S \ \ (x, b) \ r" +by (unfold interval_def, fast) + +lemma (in CLF) a_less_lub: + "\ S \ A; S \ {}; + \x \ S. (a,x) \ r; \y \ S. (y, L) \ r \ \ (a,L) \ r" +by (blast intro: transE) + +lemma (in CLF) glb_less_b: + "\ S \ A; S \ {}; + \x \ S. (x,b) \ r; \y \ S. (G, y) \ r \ \ (G,b) \ r" +by (blast intro: transE) + +lemma (in CLF) S_intv_cl: + "\ a \ A; b \ A; S \ interval r a b \\ S \ A" +by (simp add: subset_trans [OF _ interval_subset]) + +lemma (in CLF) L_in_interval: + "\ a \ A; b \ A; S \ interval r a b; + S \ {}; isLub S cl L; interval r a b \ {} \ \ L \ interval r a b" +apply (rule intervalI) +apply (rule a_less_lub) +prefer 2 apply assumption +apply (simp add: S_intv_cl) +apply (rule ballI) +apply (simp add: interval_lemma1) +apply (simp add: isLub_upper) +-- {* @{text "(L, b) \ r"} *} +apply (simp add: isLub_least interval_lemma2) +done + +lemma (in CLF) G_in_interval: + "\ a \ A; b \ A; interval r a b \ {}; S \ interval r a b; isGlb S cl G; + S \ {} \ \ G \ interval r a b" +apply (simp add: interval_dual) +apply (simp add: CLF.L_in_interval [of _ f, OF dual] + dualA_iff A_def isGlb_dual_isLub) +done + +lemma (in CLF) intervalPO: + "\ a \ A; b \ A; interval r a b \ {} \ + \ \ pset = interval r a b, order = induced (interval r a b) r \ + \ PartialOrder" +apply (rule po_subset_po) +apply (simp add: interval_subset) +done + +lemma (in CLF) intv_CL_lub: + "\ a \ A; b \ A; interval r a b \ {} \ + \ \S. S \ interval r a b \ + (\L. isLub S \ pset = interval r a b, + order = induced (interval r a b) r \ L)" +apply (intro strip) +apply (frule S_intv_cl [THEN CL_imp_ex_isLub]) +prefer 2 apply assumption +apply assumption +apply (erule exE) +-- {* define the lub for the interval as *} +apply (rule_tac x = "if S = {} then a else L" in exI) +apply (simp (no_asm_simp) add: isLub_def split del: split_if) +apply (intro impI conjI) +-- {* @{text "(if S = {} then a else L) \ interval r a b"} *} +apply (simp add: CL_imp_PO L_in_interval) +apply (simp add: left_in_interval) +-- {* lub prop 1 *} +apply (case_tac "S = {}") +-- {* @{text "S = {}, y \ S = False \ everything"} *} +apply fast +-- {* @{text "S \ {}"} *} +apply simp +-- {* @{text "\y:S. (y, L) \ induced (interval r a b) r"} *} +apply (rule ballI) +apply (simp add: induced_def L_in_interval) +apply (rule conjI) +apply (rule subsetD) +apply (simp add: S_intv_cl, assumption) +apply (simp add: isLub_upper) +-- {* @{text "\z:interval r a b. (\y:S. (y, z) \ induced (interval r a b) r \ (if S = {} then a else L, z) \ induced (interval r a b) r"} *} +apply (rule ballI) +apply (rule impI) +apply (case_tac "S = {}") +-- {* @{text "S = {}"} *} +apply simp +apply (simp add: induced_def interval_def) +apply (rule conjI) +apply (rule reflE, assumption) +apply (rule interval_not_empty) +apply (simp add: interval_def) +-- {* @{text "S \ {}"} *} +apply simp +apply (simp add: induced_def L_in_interval) +apply (rule isLub_least, assumption) +apply (rule subsetD) +prefer 2 apply assumption +apply (simp add: S_intv_cl, fast) +done + +lemmas (in CLF) intv_CL_glb = intv_CL_lub [THEN Rdual] + +lemma (in CLF) interval_is_sublattice: + "\ a \ A; b \ A; interval r a b \ {} \ + \ interval r a b \= cl" +apply (rule sublatticeI) +apply (simp add: interval_subset) +apply (rule CompleteLatticeI) +apply (simp add: intervalPO) + apply (simp add: intv_CL_lub) +apply (simp add: intv_CL_glb) +done + +lemmas (in CLF) interv_is_compl_latt = + interval_is_sublattice [THEN sublattice_imp_CL] + + +subsection {* Top and Bottom *} +lemma (in CLF) Top_dual_Bot: "Top cl = Bot (dual cl)" +by (simp add: Top_def Bot_def least_def greatest_def dualA_iff dualr_iff) + +lemma (in CLF) Bot_dual_Top: "Bot cl = Top (dual cl)" +by (simp add: Top_def Bot_def least_def greatest_def dualA_iff dualr_iff) + +lemma (in CLF) Bot_in_lattice: "Bot cl \ A" +apply (simp add: Bot_def least_def) +apply (rule_tac a="glb A cl" in someI2) +apply (simp_all add: glb_in_lattice glb_lower + r_def [symmetric] A_def [symmetric]) +done + +lemma (in CLF) Top_in_lattice: "Top cl \ A" +apply (simp add: Top_dual_Bot A_def) +apply (rule dualA_iff [THEN subst]) +apply (rule CLF.Bot_in_lattice [OF dual]) +done + +lemma (in CLF) Top_prop: "x \ A \ (x, Top cl) \ r" +apply (simp add: Top_def greatest_def) +apply (rule_tac a="lub A cl" in someI2) +apply (rule someI2) +apply (simp_all add: lub_in_lattice lub_upper + r_def [symmetric] A_def [symmetric]) +done + +lemma (in CLF) Bot_prop: "x \ A \ (Bot cl, x) \ r" +apply (simp add: Bot_dual_Top r_def) +apply (rule dualr_iff [THEN subst]) +apply (rule CLF.Top_prop [OF dual]) +apply (simp add: dualA_iff A_def) +done + +lemma (in CLF) Top_intv_not_empty: "x \ A \ interval r x (Top cl) \ {}" +apply (rule notI) +apply (drule_tac a = "Top cl" in equals0D) +apply (simp add: interval_def) +apply (simp add: refl_on_def Top_in_lattice Top_prop) +done + +lemma (in CLF) Bot_intv_not_empty: "x \ A \ interval r (Bot cl) x \ {}" +apply (simp add: Bot_dual_Top) +apply (subst interval_dual) +prefer 2 apply assumption +apply (simp add: A_def) +apply (rule dualA_iff [THEN subst]) +apply (rule CLF.Top_in_lattice [OF dual]) +apply (rule CLF.Top_intv_not_empty [OF dual]) +apply (simp add: dualA_iff A_def) +done + +subsection {* fixed points form a partial order *} + +lemma (in CLF) fixf_po: "\ pset = P, order = induced P r\ \ PartialOrder" +by (simp add: P_def fix_subset po_subset_po) + +lemma (in Tarski) Y_subset_A: "Y \ A" +apply (rule subset_trans [OF _ fix_subset]) +apply (rule Y_ss [simplified P_def]) +done + +lemma (in Tarski) lubY_in_A: "lub Y cl \ A" + by (rule Y_subset_A [THEN lub_in_lattice]) + +lemma (in Tarski) lubY_le_flubY: "(lub Y cl, f (lub Y cl)) \ r" +apply (rule lub_least) +apply (rule Y_subset_A) +apply (rule f_in_funcset [THEN funcset_mem]) +apply (rule lubY_in_A) +-- {* @{text "Y \ P \ f x = x"} *} +apply (rule ballI) +apply (rule_tac t = "x" in fix_imp_eq [THEN subst]) +apply (erule Y_ss [simplified P_def, THEN subsetD]) +-- {* @{text "reduce (f x, f (lub Y cl)) \ r to (x, lub Y cl) \ r"} by monotonicity *} +apply (rule_tac f = "f" in monotoneE) +apply (rule monotone_f) +apply (simp add: Y_subset_A [THEN subsetD]) +apply (rule lubY_in_A) +apply (simp add: lub_upper Y_subset_A) +done + +lemma (in Tarski) intY1_subset: "intY1 \ A" +apply (unfold intY1_def) +apply (rule interval_subset) +apply (rule lubY_in_A) +apply (rule Top_in_lattice) +done + +lemmas (in Tarski) intY1_elem = intY1_subset [THEN subsetD] + +lemma (in Tarski) intY1_f_closed: "x \ intY1 \ f x \ intY1" +apply (simp add: intY1_def interval_def) +apply (rule conjI) +apply (rule transE) +apply (rule lubY_le_flubY) +-- {* @{text "(f (lub Y cl), f x) \ r"} *} +apply (rule_tac f=f in monotoneE) +apply (rule monotone_f) +apply (rule lubY_in_A) +apply (simp add: intY1_def interval_def intY1_elem) +apply (simp add: intY1_def interval_def) +-- {* @{text "(f x, Top cl) \ r"} *} +apply (rule Top_prop) +apply (rule f_in_funcset [THEN funcset_mem]) +apply (simp add: intY1_def interval_def intY1_elem) +done + +lemma (in Tarski) intY1_mono: + "monotone (%x: intY1. f x) intY1 (induced intY1 r)" +apply (auto simp add: monotone_def induced_def intY1_f_closed) +apply (blast intro: intY1_elem monotone_f [THEN monotoneE]) +done + +lemma (in Tarski) intY1_is_cl: + "\ pset = intY1, order = induced intY1 r \ \ CompleteLattice" +apply (unfold intY1_def) +apply (rule interv_is_compl_latt) +apply (rule lubY_in_A) +apply (rule Top_in_lattice) +apply (rule Top_intv_not_empty) +apply (rule lubY_in_A) +done + +lemma (in Tarski) v_in_P: "v \ P" +apply (unfold P_def) +apply (rule_tac A = "intY1" in fixf_subset) +apply (rule intY1_subset) +unfolding v_def +apply (rule CLF.glbH_is_fixp [OF CLF.intro, unfolded CLF_set_def, of "\pset = intY1, order = induced intY1 r\", simplified]) +apply auto +apply (rule intY1_is_cl) +apply (erule intY1_f_closed) +apply (rule intY1_mono) +done + +lemma (in Tarski) z_in_interval: + "\ z \ P; \y\Y. (y, z) \ induced P r \ \ z \ intY1" +apply (unfold intY1_def P_def) +apply (rule intervalI) +prefer 2 + apply (erule fix_subset [THEN subsetD, THEN Top_prop]) +apply (rule lub_least) +apply (rule Y_subset_A) +apply (fast elim!: fix_subset [THEN subsetD]) +apply (simp add: induced_def) +done + +lemma (in Tarski) f'z_in_int_rel: "\ z \ P; \y\Y. (y, z) \ induced P r \ + \ ((%x: intY1. f x) z, z) \ induced intY1 r" +apply (simp add: induced_def intY1_f_closed z_in_interval P_def) +apply (simp add: fix_imp_eq [of _ f A] fix_subset [of f A, THEN subsetD] + reflE) +done + +lemma (in Tarski) tarski_full_lemma: + "\L. isLub Y \ pset = P, order = induced P r \ L" +apply (rule_tac x = "v" in exI) +apply (simp add: isLub_def) +-- {* @{text "v \ P"} *} +apply (simp add: v_in_P) +apply (rule conjI) +-- {* @{text v} is lub *} +-- {* @{text "1. \y:Y. (y, v) \ induced P r"} *} +apply (rule ballI) +apply (simp add: induced_def subsetD v_in_P) +apply (rule conjI) +apply (erule Y_ss [THEN subsetD]) +apply (rule_tac b = "lub Y cl" in transE) +apply (rule lub_upper) +apply (rule Y_subset_A, assumption) +apply (rule_tac b = "Top cl" in interval_imp_mem) +apply (simp add: v_def) +apply (fold intY1_def) +apply (rule CL.glb_in_lattice [OF CL.intro [OF intY1_is_cl], simplified]) +apply auto +apply (rule indI) + prefer 3 apply assumption + prefer 2 apply (simp add: v_in_P) +apply (unfold v_def) +apply (rule indE) +apply (rule_tac [2] intY1_subset) +apply (rule CL.glb_lower [OF CL.intro [OF intY1_is_cl], simplified]) + apply (simp add: CL_imp_PO intY1_is_cl) + apply force +apply (simp add: induced_def intY1_f_closed z_in_interval) +apply (simp add: P_def fix_imp_eq [of _ f A] reflE + fix_subset [of f A, THEN subsetD]) +done + +lemma CompleteLatticeI_simp: + "\ \ pset = A, order = r \ \ PartialOrder; + \S. S \ A \ (\L. isLub S \ pset = A, order = r \ L) \ + \ \ pset = A, order = r \ \ CompleteLattice" +by (simp add: CompleteLatticeI Rdual) + +theorem (in CLF) Tarski_full: + "\ pset = P, order = induced P r\ \ CompleteLattice" +apply (rule CompleteLatticeI_simp) +apply (rule fixf_po, clarify) +apply (simp add: P_def A_def r_def) +apply (rule Tarski.tarski_full_lemma [OF Tarski.intro [OF _ Tarski_axioms.intro]]) +proof - show "CLF cl f" .. qed + +end -- cgit v1.2.3