--- a/src/HOL/Relation.thy Sun Feb 26 21:25:54 2012 +0100
+++ b/src/HOL/Relation.thy Sun Feb 26 21:26:28 2012 +0100
@@ -8,7 +8,7 @@
imports Datatype Finite_Set
begin
-subsection {* Classical rules for reasoning on predicates *}
+text {* A preliminary: classical rules for reasoning on predicates *}
(* CANDIDATE declare predicate1I [Pure.intro!, intro!] *)
declare predicate1D [Pure.dest?, dest?]
@@ -42,8 +42,23 @@
declare SUP1_E [elim!]
declare SUP2_E [elim!]
+subsection {* Fundamental *}
-subsection {* Conversions between set and predicate relations *}
+subsubsection {* Relations as sets of pairs *}
+
+type_synonym 'a rel = "('a * 'a) set"
+
+lemma subrelI: -- {* Version of @{thm [source] subsetI} for binary relations *}
+ "(\<And>x y. (x, y) \<in> r \<Longrightarrow> (x, y) \<in> s) \<Longrightarrow> r \<subseteq> s"
+ by auto
+
+lemma lfp_induct2: -- {* Version of @{thm [source] lfp_induct} for binary relations *}
+ "(a, b) \<in> lfp f \<Longrightarrow> mono f \<Longrightarrow>
+ (\<And>a b. (a, b) \<in> f (lfp f \<inter> {(x, y). P x y}) \<Longrightarrow> P a b) \<Longrightarrow> P a b"
+ using lfp_induct_set [of "(a, b)" f "prod_case P"] by auto
+
+
+subsubsection {* Conversions between set and predicate relations *}
lemma pred_equals_eq [pred_set_conv]: "((\<lambda>x. x \<in> R) = (\<lambda>x. x \<in> S)) \<longleftrightarrow> (R = S)"
by (simp add: set_eq_iff fun_eq_iff)
@@ -94,30 +109,21 @@
by (simp add: SUP_apply fun_eq_iff)
-subsection {* Relations as sets of pairs *}
-
-type_synonym 'a rel = "('a * 'a) set"
-
-lemma subrelI: -- {* Version of @{thm [source] subsetI} for binary relations *}
- "(\<And>x y. (x, y) \<in> r \<Longrightarrow> (x, y) \<in> s) \<Longrightarrow> r \<subseteq> s"
- by auto
-
-lemma lfp_induct2: -- {* Version of @{thm [source] lfp_induct} for binary relations *}
- "(a, b) \<in> lfp f \<Longrightarrow> mono f \<Longrightarrow>
- (\<And>a b. (a, b) \<in> f (lfp f \<inter> {(x, y). P x y}) \<Longrightarrow> P a b) \<Longrightarrow> P a b"
- using lfp_induct_set [of "(a, b)" f "prod_case P"] by auto
-
+subsection {* Properties of relations *}
subsubsection {* Reflexivity *}
definition
- refl_on :: "['a set, ('a * 'a) set] => bool" where -- {* reflexivity over a set *}
+ refl_on :: "'a set \<Rightarrow> ('a \<times> 'a) set \<Rightarrow> bool" where
"refl_on A r \<longleftrightarrow> r \<subseteq> A \<times> A & (ALL x: A. (x,x) : r)"
abbreviation
refl :: "('a * 'a) set => bool" where -- {* reflexivity over a type *}
"refl \<equiv> refl_on UNIV"
+definition reflp :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
+ "reflp r \<longleftrightarrow> refl {(x, y). r x y}"
+
lemma refl_onI: "r \<subseteq> A \<times> A ==> (!!x. x : A ==> (x, x) : r) ==> refl_on A r"
by (unfold refl_on_def) (iprover intro!: ballI)
@@ -130,6 +136,15 @@
lemma refl_onD2: "refl_on A r ==> (x, y) : r ==> y : A"
by (unfold refl_on_def) blast
+lemma reflpI:
+ "(\<And>x. r x x) \<Longrightarrow> reflp r"
+ by (auto intro: refl_onI simp add: reflp_def)
+
+lemma reflpE:
+ assumes "reflp r"
+ obtains "r x x"
+ using assms by (auto dest: refl_onD simp add: reflp_def)
+
lemma refl_on_Int: "refl_on A r ==> refl_on B s ==> refl_on (A \<inter> B) (r \<inter> s)"
by (unfold refl_on_def) blast
@@ -152,30 +167,21 @@
by (auto intro: refl_onI dest: refl_onD refl_onD1 refl_onD2)
-subsubsection {* Antisymmetry *}
+subsubsection {* Irreflexivity *}
definition
- antisym :: "('a * 'a) set => bool" where -- {* antisymmetry predicate *}
- "antisym r \<longleftrightarrow> (ALL x y. (x,y):r --> (y,x):r --> x=y)"
-
-lemma antisymI:
- "(!!x y. (x, y) : r ==> (y, x) : r ==> x=y) ==> antisym r"
-by (unfold antisym_def) iprover
+ irrefl :: "('a * 'a) set => bool" where
+ "irrefl r \<longleftrightarrow> (\<forall>x. (x,x) \<notin> r)"
-lemma antisymD: "antisym r ==> (a, b) : r ==> (b, a) : r ==> a = b"
-by (unfold antisym_def) iprover
-
-lemma antisym_subset: "r \<subseteq> s ==> antisym s ==> antisym r"
-by (unfold antisym_def) blast
-
-lemma antisym_empty [simp]: "antisym {}"
-by (unfold antisym_def) blast
+lemma irrefl_distinct [code]:
+ "irrefl r \<longleftrightarrow> (\<forall>(x, y) \<in> r. x \<noteq> y)"
+ by (auto simp add: irrefl_def)
subsubsection {* Symmetry *}
definition
- sym :: "('a * 'a) set => bool" where -- {* symmetry predicate *}
+ sym :: "('a * 'a) set => bool" where
"sym r \<longleftrightarrow> (ALL x y. (x,y): r --> (y,x): r)"
lemma symI: "(!!a b. (a, b) : r ==> (b, a) : r) ==> sym r"
@@ -184,6 +190,18 @@
lemma symD: "sym r ==> (a, b) : r ==> (b, a) : r"
by (unfold sym_def, blast)
+definition symp :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
+ "symp r \<longleftrightarrow> sym {(x, y). r x y}"
+
+lemma sympI:
+ "(\<And>x y. r x y \<Longrightarrow> r y x) \<Longrightarrow> symp r"
+ by (auto intro: symI simp add: symp_def)
+
+lemma sympE:
+ assumes "symp r" and "r x y"
+ obtains "r y x"
+ using assms by (auto dest: symD simp add: symp_def)
+
lemma sym_Int: "sym r ==> sym s ==> sym (r \<inter> s)"
by (fast intro: symI dest: symD)
@@ -197,16 +215,35 @@
by (fast intro: symI dest: symD)
+subsubsection {* Antisymmetry *}
+
+definition
+ antisym :: "('a * 'a) set => bool" where
+ "antisym r \<longleftrightarrow> (ALL x y. (x,y):r --> (y,x):r --> x=y)"
+
+lemma antisymI:
+ "(!!x y. (x, y) : r ==> (y, x) : r ==> x=y) ==> antisym r"
+by (unfold antisym_def) iprover
+
+lemma antisymD: "antisym r ==> (a, b) : r ==> (b, a) : r ==> a = b"
+by (unfold antisym_def) iprover
+
+abbreviation antisymP :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
+ "antisymP r \<equiv> antisym {(x, y). r x y}"
+
+lemma antisym_subset: "r \<subseteq> s ==> antisym s ==> antisym r"
+by (unfold antisym_def) blast
+
+lemma antisym_empty [simp]: "antisym {}"
+by (unfold antisym_def) blast
+
+
subsubsection {* Transitivity *}
definition
- trans :: "('a * 'a) set => bool" where -- {* transitivity predicate *}
+ trans :: "('a * 'a) set => bool" where
"trans r \<longleftrightarrow> (ALL x y z. (x,y):r --> (y,z):r --> (x,z):r)"
-lemma trans_join [code]:
- "trans r \<longleftrightarrow> (\<forall>(x, y1) \<in> r. \<forall>(y2, z) \<in> r. y1 = y2 \<longrightarrow> (x, z) \<in> r)"
- by (auto simp add: trans_def)
-
lemma transI:
"(!!x y z. (x, y) : r ==> (y, z) : r ==> (x, z) : r) ==> trans r"
by (unfold trans_def) iprover
@@ -214,22 +251,30 @@
lemma transD: "trans r ==> (a, b) : r ==> (b, c) : r ==> (a, c) : r"
by (unfold trans_def) iprover
+abbreviation transP :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
+ "transP r \<equiv> trans {(x, y). r x y}"
+
+definition transp :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
+ "transp r \<longleftrightarrow> trans {(x, y). r x y}"
+
+lemma transpI:
+ "(\<And>x y z. r x y \<Longrightarrow> r y z \<Longrightarrow> r x z) \<Longrightarrow> transp r"
+ by (auto intro: transI simp add: transp_def)
+
+lemma transpE:
+ assumes "transp r" and "r x y" and "r y z"
+ obtains "r x z"
+ using assms by (auto dest: transD simp add: transp_def)
+
lemma trans_Int: "trans r ==> trans s ==> trans (r \<inter> s)"
by (fast intro: transI elim: transD)
lemma trans_INTER: "ALL x:S. trans (r x) ==> trans (INTER S r)"
by (fast intro: transI elim: transD)
-
-subsubsection {* Irreflexivity *}
-
-definition
- irrefl :: "('a * 'a) set => bool" where
- "irrefl r \<longleftrightarrow> (\<forall>x. (x,x) \<notin> r)"
-
-lemma irrefl_distinct [code]:
- "irrefl r \<longleftrightarrow> (\<forall>(x, y) \<in> r. x \<noteq> y)"
- by (auto simp add: irrefl_def)
+lemma trans_join [code]:
+ "trans r \<longleftrightarrow> (\<forall>(x, y1) \<in> r. \<forall>(y2, z) \<in> r. y1 = y2 \<longrightarrow> (x, z) \<in> r)"
+ by (auto simp add: trans_def)
subsubsection {* Totality *}
@@ -258,15 +303,20 @@
"single_valued r ==> (x, y) : r ==> (x, z) : r ==> y = z"
by (simp add: single_valued_def)
+abbreviation single_valuedP :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> bool" where
+ "single_valuedP r \<equiv> single_valued {(x, y). r x y}"
+
lemma single_valued_subset:
"r \<subseteq> s ==> single_valued s ==> single_valued r"
by (unfold single_valued_def) blast
+subsection {* Relation operations *}
+
subsubsection {* The identity relation *}
definition
- Id :: "('a * 'a) set" where -- {* the identity relation *}
+ Id :: "('a * 'a) set" where
"Id = {p. EX x. p = (x,x)}"
lemma IdI [intro]: "(a, a) : Id"
@@ -307,7 +357,7 @@
subsubsection {* Diagonal: identity over a set *}
definition
- Id_on :: "'a set => ('a * 'a) set" where -- {* diagonal: identity over a set *}
+ Id_on :: "'a set => ('a * 'a) set" where
"Id_on A = (\<Union>x\<in>A. {(x,x)})"
lemma Id_on_empty [simp]: "Id_on {} = {}"
@@ -350,12 +400,11 @@
by (unfold single_valued_def) blast
-subsubsection {* Composition of two relations *}
+subsubsection {* Composition *}
-definition
- rel_comp :: "[('a * 'b) set, ('b * 'c) set] => ('a * 'c) set"
- (infixr "O" 75) where
- "r O s = {(x,z). EX y. (x, y) : r & (y, z) : s}"
+definition rel_comp :: "('a \<times> 'b) set \<Rightarrow> ('b \<times> 'c) set \<Rightarrow> ('a * 'c) set" (infixr "O" 75)
+where
+ "r O s = {(x, z). \<exists>y. (x, y) \<in> r \<and> (y, z) \<in> s}"
lemma rel_compI [intro]:
"(a, b) : r ==> (b, c) : s ==> (a, c) : r O s"
@@ -365,6 +414,17 @@
(!!x y z. xz = (x, z) ==> (x, y) : r ==> (y, z) : s ==> P) ==> P"
by (unfold rel_comp_def) (iprover elim!: CollectE splitE exE conjE)
+inductive pred_comp :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> ('b \<Rightarrow> 'c \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> 'c \<Rightarrow> bool" (infixr "OO" 75)
+for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" and s :: "'b \<Rightarrow> 'c \<Rightarrow> bool"
+where
+ pred_compI [intro]: "r a b \<Longrightarrow> s b c \<Longrightarrow> (r OO s) a c"
+
+inductive_cases pred_compE [elim!]: "(r OO s) a c"
+
+lemma pred_comp_rel_comp_eq [pred_set_conv]:
+ "((\<lambda>x y. (x, y) \<in> r) OO (\<lambda>x y. (x, y) \<in> s)) = (\<lambda>x y. (x, y) \<in> r O s)"
+ by (auto simp add: fun_eq_iff)
+
lemma rel_compEpair:
"(a, c) : r O s ==> (!!y. (a, y) : r ==> (y, c) : s ==> P) ==> P"
by (iprover elim: rel_compE Pair_inject ssubst)
@@ -421,19 +481,58 @@
notation (xsymbols)
converse ("(_\<inverse>)" [1000] 999)
-lemma converse_iff [iff]: "((a,b): r^-1) = ((b,a) : r)"
-by (simp add: converse_def)
+lemma converseI [sym]: "(a, b) : r ==> (b, a) : r^-1"
+ by (simp add: converse_def)
-lemma converseI[sym]: "(a, b) : r ==> (b, a) : r^-1"
-by (simp add: converse_def)
-
-lemma converseD[sym]: "(a,b) : r^-1 ==> (b, a) : r"
-by (simp add: converse_def)
+lemma converseD [sym]: "(a,b) : r^-1 ==> (b, a) : r"
+ by (simp add: converse_def)
lemma converseE [elim!]:
"yx : r^-1 ==> (!!x y. yx = (y, x) ==> (x, y) : r ==> P) ==> P"
-- {* More general than @{text converseD}, as it ``splits'' the member of the relation. *}
-by (unfold converse_def) (iprover elim!: CollectE splitE bexE)
+ by (unfold converse_def) (iprover elim!: CollectE splitE bexE)
+
+lemma converse_iff [iff]: "((a,b): r^-1) = ((b,a) : r)"
+ by (simp add: converse_def)
+
+inductive conversep :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'b \<Rightarrow> 'a \<Rightarrow> bool" ("(_^--1)" [1000] 1000)
+ for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" where
+ conversepI: "r a b \<Longrightarrow> r^--1 b a"
+
+notation (xsymbols)
+ conversep ("(_\<inverse>\<inverse>)" [1000] 1000)
+
+lemma conversepD:
+ assumes ab: "r^--1 a b"
+ shows "r b a" using ab
+ by cases simp
+
+lemma conversep_iff [iff]: "r^--1 a b = r b a"
+ by (iprover intro: conversepI dest: conversepD)
+
+lemma conversep_converse_eq [pred_set_conv]:
+ "(\<lambda>x y. (x, y) \<in> r)^--1 = (\<lambda>x y. (x, y) \<in> r^-1)"
+ apply (auto simp add: fun_eq_iff)
+ oops
+
+lemma conversep_conversep [simp]: "(r^--1)^--1 = r"
+ by (iprover intro: order_antisym conversepI dest: conversepD)
+
+lemma converse_pred_comp: "(r OO s)^--1 = s^--1 OO r^--1"
+ by (iprover intro: order_antisym conversepI pred_compI
+ elim: pred_compE dest: conversepD)
+
+lemma converse_meet: "(r \<sqinter> s)^--1 = r^--1 \<sqinter> s^--1"
+ by (simp add: inf_fun_def) (iprover intro: conversepI ext dest: conversepD)
+
+lemma converse_join: "(r \<squnion> s)^--1 = r^--1 \<squnion> s^--1"
+ by (simp add: sup_fun_def) (iprover intro: conversepI ext dest: conversepD)
+
+lemma conversep_noteq [simp]: "(op \<noteq>)^--1 = op \<noteq>"
+ by (auto simp add: fun_eq_iff)
+
+lemma conversep_eq [simp]: "(op =)^--1 = op ="
+ by (auto simp add: fun_eq_iff)
lemma converse_converse [simp]: "(r^-1)^-1 = r"
by (unfold converse_def) blast
@@ -523,58 +622,6 @@
"a : Domain r ==> (!!y. (a, y) : r ==> P) ==> P"
by (iprover dest!: iffD1 [OF Domain_iff])
-lemma Domain_fst [code]:
- "Domain r = fst ` r"
- by (auto simp add: image_def Bex_def)
-
-lemma Domain_empty [simp]: "Domain {} = {}"
-by blast
-
-lemma Domain_empty_iff: "Domain r = {} \<longleftrightarrow> r = {}"
- by auto
-
-lemma Domain_insert: "Domain (insert (a, b) r) = insert a (Domain r)"
-by blast
-
-lemma Domain_Id [simp]: "Domain Id = UNIV"
-by blast
-
-lemma Domain_Id_on [simp]: "Domain (Id_on A) = A"
-by blast
-
-lemma Domain_Un_eq: "Domain(A \<union> B) = Domain(A) \<union> Domain(B)"
-by blast
-
-lemma Domain_Int_subset: "Domain(A \<inter> B) \<subseteq> Domain(A) \<inter> Domain(B)"
-by blast
-
-lemma Domain_Diff_subset: "Domain(A) - Domain(B) \<subseteq> Domain(A - B)"
-by blast
-
-lemma Domain_Union: "Domain (Union S) = (\<Union>A\<in>S. Domain A)"
-by blast
-
-lemma Domain_converse[simp]: "Domain(r^-1) = Range r"
-by(auto simp:Range_def)
-
-lemma Domain_mono: "r \<subseteq> s ==> Domain r \<subseteq> Domain s"
-by blast
-
-lemma fst_eq_Domain: "fst ` R = Domain R"
- by force
-
-lemma Domain_dprod [simp]: "Domain (dprod r s) = uprod (Domain r) (Domain s)"
-by auto
-
-lemma Domain_dsum [simp]: "Domain (dsum r s) = usum (Domain r) (Domain s)"
-by auto
-
-lemma Domain_Collect_split [simp]: "Domain {(x, y). P x y} = {x. EX y. P x y}"
-by auto
-
-lemma finite_Domain: "finite r ==> finite (Domain r)"
- by (induct set: finite) (auto simp add: Domain_insert)
-
lemma Range_iff: "(a : Range r) = (EX y. (y, a) : r)"
by (simp add: Domain_def Range_def)
@@ -584,66 +631,136 @@
lemma RangeE [elim!]: "b : Range r ==> (!!x. (x, b) : r ==> P) ==> P"
by (unfold Range_def) (iprover elim!: DomainE dest!: converseD)
+inductive DomainP :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool"
+ for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" where
+ DomainPI [intro]: "r a b \<Longrightarrow> DomainP r a"
+
+inductive_cases DomainPE [elim!]: "DomainP r a"
+
+lemma DomainP_Domain_eq [pred_set_conv]: "DomainP (\<lambda>x y. (x, y) \<in> r) = (\<lambda>x. x \<in> Domain r)"
+ by (blast intro!: Orderings.order_antisym predicate1I)
+
+inductive RangeP :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'b \<Rightarrow> bool"
+ for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" where
+ RangePI [intro]: "r a b \<Longrightarrow> RangeP r b"
+
+inductive_cases RangePE [elim!]: "RangeP r b"
+
+lemma RangeP_Range_eq [pred_set_conv]: "RangeP (\<lambda>x y. (x, y) \<in> r) = (\<lambda>x. x \<in> Range r)"
+ by (auto intro!: Orderings.order_antisym predicate1I)
+
+lemma Domain_fst [code]:
+ "Domain r = fst ` r"
+ by (auto simp add: image_def Bex_def)
+
+lemma Domain_empty [simp]: "Domain {} = {}"
+ by blast
+
+lemma Domain_empty_iff: "Domain r = {} \<longleftrightarrow> r = {}"
+ by auto
+
+lemma Domain_insert: "Domain (insert (a, b) r) = insert a (Domain r)"
+ by blast
+
+lemma Domain_Id [simp]: "Domain Id = UNIV"
+ by blast
+
+lemma Domain_Id_on [simp]: "Domain (Id_on A) = A"
+ by blast
+
+lemma Domain_Un_eq: "Domain(A \<union> B) = Domain(A) \<union> Domain(B)"
+ by blast
+
+lemma Domain_Int_subset: "Domain(A \<inter> B) \<subseteq> Domain(A) \<inter> Domain(B)"
+ by blast
+
+lemma Domain_Diff_subset: "Domain(A) - Domain(B) \<subseteq> Domain(A - B)"
+ by blast
+
+lemma Domain_Union: "Domain (Union S) = (\<Union>A\<in>S. Domain A)"
+ by blast
+
+lemma Domain_converse[simp]: "Domain(r^-1) = Range r"
+ by(auto simp: Range_def)
+
+lemma Domain_mono: "r \<subseteq> s ==> Domain r \<subseteq> Domain s"
+ by blast
+
+lemma fst_eq_Domain: "fst ` R = Domain R"
+ by force
+
+lemma Domain_dprod [simp]: "Domain (dprod r s) = uprod (Domain r) (Domain s)"
+ by auto
+
+lemma Domain_dsum [simp]: "Domain (dsum r s) = usum (Domain r) (Domain s)"
+ by auto
+
+lemma Domain_Collect_split [simp]: "Domain {(x, y). P x y} = {x. EX y. P x y}"
+ by auto
+
+lemma finite_Domain: "finite r ==> finite (Domain r)"
+ by (induct set: finite) (auto simp add: Domain_insert)
+
lemma Range_snd [code]:
"Range r = snd ` r"
by (auto simp add: image_def Bex_def)
lemma Range_empty [simp]: "Range {} = {}"
-by blast
+ by blast
lemma Range_empty_iff: "Range r = {} \<longleftrightarrow> r = {}"
by auto
lemma Range_insert: "Range (insert (a, b) r) = insert b (Range r)"
-by blast
+ by blast
lemma Range_Id [simp]: "Range Id = UNIV"
-by blast
+ by blast
lemma Range_Id_on [simp]: "Range (Id_on A) = A"
-by auto
+ by auto
lemma Range_Un_eq: "Range(A \<union> B) = Range(A) \<union> Range(B)"
-by blast
+ by blast
lemma Range_Int_subset: "Range(A \<inter> B) \<subseteq> Range(A) \<inter> Range(B)"
-by blast
+ by blast
lemma Range_Diff_subset: "Range(A) - Range(B) \<subseteq> Range(A - B)"
-by blast
+ by blast
lemma Range_Union: "Range (Union S) = (\<Union>A\<in>S. Range A)"
-by blast
+ by blast
-lemma Range_converse[simp]: "Range(r^-1) = Domain r"
-by blast
+lemma Range_converse [simp]: "Range(r^-1) = Domain r"
+ by blast
lemma snd_eq_Range: "snd ` R = Range R"
by force
lemma Range_Collect_split [simp]: "Range {(x, y). P x y} = {y. EX x. P x y}"
-by auto
+ by auto
lemma finite_Range: "finite r ==> finite (Range r)"
by (induct set: finite) (auto simp add: Range_insert)
lemma mono_Field: "r \<subseteq> s \<Longrightarrow> Field r \<subseteq> Field s"
-by(auto simp:Field_def Domain_def Range_def)
+ by (auto simp: Field_def Domain_def Range_def)
lemma Field_empty[simp]: "Field {} = {}"
-by(auto simp:Field_def)
+ by (auto simp: Field_def)
-lemma Field_insert[simp]: "Field (insert (a,b) r) = {a,b} \<union> Field r"
-by(auto simp:Field_def)
+lemma Field_insert [simp]: "Field (insert (a, b) r) = {a, b} \<union> Field r"
+ by (auto simp: Field_def)
-lemma Field_Un[simp]: "Field (r \<union> s) = Field r \<union> Field s"
-by(auto simp:Field_def)
+lemma Field_Un [simp]: "Field (r \<union> s) = Field r \<union> Field s"
+ by (auto simp: Field_def)
-lemma Field_Union[simp]: "Field (\<Union>R) = \<Union>(Field ` R)"
-by(auto simp:Field_def)
+lemma Field_Union [simp]: "Field (\<Union>R) = \<Union>(Field ` R)"
+ by (auto simp: Field_def)
-lemma Field_converse[simp]: "Field(r^-1) = Field r"
-by(auto simp:Field_def)
+lemma Field_converse [simp]: "Field(r^-1) = Field r"
+ by (auto simp: Field_def)
lemma finite_Field: "finite r ==> finite (Field r)"
-- {* A finite relation has a finite field (@{text "= domain \<union> range"}. *}
@@ -740,6 +857,12 @@
inv_image :: "('b * 'b) set => ('a => 'b) => ('a * 'a) set" where
"inv_image r f = {(x, y). (f x, f y) : r}"
+definition inv_imagep :: "('b \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> bool" where
+ "inv_imagep r f = (\<lambda>x y. r (f x) (f y))"
+
+lemma [pred_set_conv]: "inv_imagep (\<lambda>x y. (x, y) \<in> r) f = (\<lambda>x y. (x, y) \<in> inv_image r f)"
+ by (simp add: inv_image_def inv_imagep_def)
+
lemma sym_inv_image: "sym r ==> sym (inv_image r f)"
by (unfold sym_def inv_image_def) blast
@@ -755,95 +878,6 @@
lemma converse_inv_image[simp]: "(inv_image R f)^-1 = inv_image (R^-1) f"
unfolding inv_image_def converse_def by auto
-
-subsection {* Relations as binary predicates *}
-
-subsubsection {* Composition *}
-
-inductive pred_comp :: "['a \<Rightarrow> 'b \<Rightarrow> bool, 'b \<Rightarrow> 'c \<Rightarrow> bool] \<Rightarrow> 'a \<Rightarrow> 'c \<Rightarrow> bool" (infixr "OO" 75)
- for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" and s :: "'b \<Rightarrow> 'c \<Rightarrow> bool" where
- pred_compI [intro]: "r a b \<Longrightarrow> s b c \<Longrightarrow> (r OO s) a c"
-
-inductive_cases pred_compE [elim!]: "(r OO s) a c"
-
-lemma pred_comp_rel_comp_eq [pred_set_conv]:
- "((\<lambda>x y. (x, y) \<in> r) OO (\<lambda>x y. (x, y) \<in> s)) = (\<lambda>x y. (x, y) \<in> r O s)"
- by (auto simp add: fun_eq_iff)
-
-
-subsubsection {* Converse *}
-
-inductive conversep :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'b \<Rightarrow> 'a \<Rightarrow> bool" ("(_^--1)" [1000] 1000)
- for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" where
- conversepI: "r a b \<Longrightarrow> r^--1 b a"
-
-notation (xsymbols)
- conversep ("(_\<inverse>\<inverse>)" [1000] 1000)
-
-lemma conversepD:
- assumes ab: "r^--1 a b"
- shows "r b a" using ab
- by cases simp
-
-lemma conversep_iff [iff]: "r^--1 a b = r b a"
- by (iprover intro: conversepI dest: conversepD)
-
-lemma conversep_converse_eq [pred_set_conv]:
- "(\<lambda>x y. (x, y) \<in> r)^--1 = (\<lambda>x y. (x, y) \<in> r^-1)"
- by (auto simp add: fun_eq_iff)
-
-lemma conversep_conversep [simp]: "(r^--1)^--1 = r"
- by (iprover intro: order_antisym conversepI dest: conversepD)
-
-lemma converse_pred_comp: "(r OO s)^--1 = s^--1 OO r^--1"
- by (iprover intro: order_antisym conversepI pred_compI
- elim: pred_compE dest: conversepD)
-
-lemma converse_meet: "(r \<sqinter> s)^--1 = r^--1 \<sqinter> s^--1"
- by (simp add: inf_fun_def) (iprover intro: conversepI ext dest: conversepD)
-
-lemma converse_join: "(r \<squnion> s)^--1 = r^--1 \<squnion> s^--1"
- by (simp add: sup_fun_def) (iprover intro: conversepI ext dest: conversepD)
-
-lemma conversep_noteq [simp]: "(op \<noteq>)^--1 = op \<noteq>"
- by (auto simp add: fun_eq_iff)
-
-lemma conversep_eq [simp]: "(op =)^--1 = op ="
- by (auto simp add: fun_eq_iff)
-
-
-subsubsection {* Domain *}
-
-inductive DomainP :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool"
- for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" where
- DomainPI [intro]: "r a b \<Longrightarrow> DomainP r a"
-
-inductive_cases DomainPE [elim!]: "DomainP r a"
-
-lemma DomainP_Domain_eq [pred_set_conv]: "DomainP (\<lambda>x y. (x, y) \<in> r) = (\<lambda>x. x \<in> Domain r)"
- by (blast intro!: Orderings.order_antisym predicate1I)
-
-
-subsubsection {* Range *}
-
-inductive RangeP :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'b \<Rightarrow> bool"
- for r :: "'a \<Rightarrow> 'b \<Rightarrow> bool" where
- RangePI [intro]: "r a b \<Longrightarrow> RangeP r b"
-
-inductive_cases RangePE [elim!]: "RangeP r b"
-
-lemma RangeP_Range_eq [pred_set_conv]: "RangeP (\<lambda>x y. (x, y) \<in> r) = (\<lambda>x. x \<in> Range r)"
- by (blast intro!: Orderings.order_antisym predicate1I)
-
-
-subsubsection {* Inverse image *}
-
-definition inv_imagep :: "('b \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> bool" where
- "inv_imagep r f = (\<lambda>x y. r (f x) (f y))"
-
-lemma [pred_set_conv]: "inv_imagep (\<lambda>x y. (x, y) \<in> r) f = (\<lambda>x y. (x, y) \<in> inv_image r f)"
- by (simp add: inv_image_def inv_imagep_def)
-
lemma in_inv_imagep [simp]: "inv_imagep r f x y = r (f x) (f y)"
by (simp add: inv_imagep_def)
@@ -858,55 +892,5 @@
lemmas Powp_mono [mono] = Pow_mono [to_pred]
-
-subsubsection {* Properties of predicate relations *}
-
-abbreviation antisymP :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
- "antisymP r \<equiv> antisym {(x, y). r x y}"
-
-abbreviation transP :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
- "transP r \<equiv> trans {(x, y). r x y}"
-
-abbreviation single_valuedP :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> bool" where
- "single_valuedP r \<equiv> single_valued {(x, y). r x y}"
-
-(*FIXME inconsistencies: abbreviations vs. definitions, suffix `P` vs. suffix `p`*)
-
-definition reflp :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
- "reflp r \<longleftrightarrow> refl {(x, y). r x y}"
-
-definition symp :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
- "symp r \<longleftrightarrow> sym {(x, y). r x y}"
-
-definition transp :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> bool" where
- "transp r \<longleftrightarrow> trans {(x, y). r x y}"
-
-lemma reflpI:
- "(\<And>x. r x x) \<Longrightarrow> reflp r"
- by (auto intro: refl_onI simp add: reflp_def)
-
-lemma reflpE:
- assumes "reflp r"
- obtains "r x x"
- using assms by (auto dest: refl_onD simp add: reflp_def)
-
-lemma sympI:
- "(\<And>x y. r x y \<Longrightarrow> r y x) \<Longrightarrow> symp r"
- by (auto intro: symI simp add: symp_def)
-
-lemma sympE:
- assumes "symp r" and "r x y"
- obtains "r y x"
- using assms by (auto dest: symD simp add: symp_def)
-
-lemma transpI:
- "(\<And>x y z. r x y \<Longrightarrow> r y z \<Longrightarrow> r x z) \<Longrightarrow> transp r"
- by (auto intro: transI simp add: transp_def)
-
-lemma transpE:
- assumes "transp r" and "r x y" and "r y z"
- obtains "r x z"
- using assms by (auto dest: transD simp add: transp_def)
-
end