src/HOL/Finite_Set.thy
author wenzelm
Sat, 07 Apr 2012 16:41:59 +0200
changeset 47389 e8552cba702d
parent 47221 7205eb4a0a05
child 48063 f02b4302d5dd
permissions -rw-r--r--
explicit checks stable_finished_theory/stable_command allow parallel asynchronous command transactions; tuned;
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
     1
(*  Title:      HOL/Finite_Set.thy
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
     2
    Author:     Tobias Nipkow, Lawrence C Paulson and Markus Wenzel
16775
c1b87ef4a1c3 added lemmas to OrderedGroup.thy (reasoning about signs, absolute value, triangle inequalities)
avigad
parents: 16760
diff changeset
     3
                with contributions by Jeremy Avigad
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
     4
*)
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
     5
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
     6
header {* Finite sets *}
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
     7
15131
c69542757a4d New theory header syntax.
nipkow
parents: 15124
diff changeset
     8
theory Finite_Set
38400
9bfcb1507c6b import swap prevents strange failure of SML code generator for datatypes
haftmann
parents: 37770
diff changeset
     9
imports Option Power
15131
c69542757a4d New theory header syntax.
nipkow
parents: 15124
diff changeset
    10
begin
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
    11
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
    12
subsection {* Predicate for finite sets *}
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
    13
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    14
inductive finite :: "'a set \<Rightarrow> bool"
22262
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
    15
  where
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
    16
    emptyI [simp, intro!]: "finite {}"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    17
  | insertI [simp, intro!]: "finite A \<Longrightarrow> finite (insert a A)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    18
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    19
lemma finite_induct [case_names empty insert, induct set: finite]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    20
  -- {* Discharging @{text "x \<notin> F"} entails extra work. *}
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    21
  assumes "finite F"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    22
  assumes "P {}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    23
    and insert: "\<And>x F. finite F \<Longrightarrow> x \<notin> F \<Longrightarrow> P F \<Longrightarrow> P (insert x F)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    24
  shows "P F"
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
    25
using `finite F`
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
    26
proof induct
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    27
  show "P {}" by fact
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    28
  fix x F assume F: "finite F" and P: "P F"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    29
  show "P (insert x F)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    30
  proof cases
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    31
    assume "x \<in> F"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    32
    hence "insert x F = F" by (rule insert_absorb)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    33
    with P show ?thesis by (simp only:)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    34
  next
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    35
    assume "x \<notin> F"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    36
    from F this P show ?thesis by (rule insert)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    37
  qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    38
qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    39
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    40
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    41
subsubsection {* Choice principles *}
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
    42
13737
e564c3d2d174 added a few lemmas
nipkow
parents: 13735
diff changeset
    43
lemma ex_new_if_finite: -- "does not depend on def of finite at all"
14661
9ead82084de8 tuned notation;
wenzelm
parents: 14565
diff changeset
    44
  assumes "\<not> finite (UNIV :: 'a set)" and "finite A"
9ead82084de8 tuned notation;
wenzelm
parents: 14565
diff changeset
    45
  shows "\<exists>a::'a. a \<notin> A"
9ead82084de8 tuned notation;
wenzelm
parents: 14565
diff changeset
    46
proof -
28823
dcbef866c9e2 tuned unfold_locales invocation
haftmann
parents: 27981
diff changeset
    47
  from assms have "A \<noteq> UNIV" by blast
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    48
  then show ?thesis by blast
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
    49
qed
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
    50
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    51
text {* A finite choice principle. Does not need the SOME choice operator. *}
15484
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
    52
29923
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    53
lemma finite_set_choice:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    54
  "finite A \<Longrightarrow> \<forall>x\<in>A. \<exists>y. P x y \<Longrightarrow> \<exists>f. \<forall>x\<in>A. P x (f x)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    55
proof (induct rule: finite_induct)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    56
  case empty then show ?case by simp
29923
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    57
next
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    58
  case (insert a A)
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    59
  then obtain f b where f: "ALL x:A. P x (f x)" and ab: "P a b" by auto
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    60
  show ?case (is "EX f. ?P f")
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    61
  proof
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    62
    show "?P(%x. if x = a then b else f x)" using f ab by auto
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    63
  qed
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    64
qed
24f56736c56f added finite_set_choice
nipkow
parents: 29920
diff changeset
    65
23878
bd651ecd4b8a simplified HOL bootstrap
haftmann
parents: 23736
diff changeset
    66
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    67
subsubsection {* Finite sets are the images of initial segments of natural numbers *}
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    68
15510
9de204d7b699 new foldSet proofs
paulson
parents: 15509
diff changeset
    69
lemma finite_imp_nat_seg_image_inj_on:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    70
  assumes "finite A" 
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    71
  shows "\<exists>(n::nat) f. A = f ` {i. i < n} \<and> inj_on f {i. i < n}"
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
    72
using assms
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
    73
proof induct
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    74
  case empty
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    75
  show ?case
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    76
  proof
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    77
    show "\<exists>f. {} = f ` {i::nat. i < 0} \<and> inj_on f {i. i < 0}" by simp 
15510
9de204d7b699 new foldSet proofs
paulson
parents: 15509
diff changeset
    78
  qed
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    79
next
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    80
  case (insert a A)
23389
aaca6a8e5414 tuned proofs: avoid implicit prems;
wenzelm
parents: 23277
diff changeset
    81
  have notinA: "a \<notin> A" by fact
15510
9de204d7b699 new foldSet proofs
paulson
parents: 15509
diff changeset
    82
  from insert.hyps obtain n f
9de204d7b699 new foldSet proofs
paulson
parents: 15509
diff changeset
    83
    where "A = f ` {i::nat. i < n}" "inj_on f {i. i < n}" by blast
9de204d7b699 new foldSet proofs
paulson
parents: 15509
diff changeset
    84
  hence "insert a A = f(n:=a) ` {i. i < Suc n}"
9de204d7b699 new foldSet proofs
paulson
parents: 15509
diff changeset
    85
        "inj_on (f(n:=a)) {i. i < Suc n}" using notinA
9de204d7b699 new foldSet proofs
paulson
parents: 15509
diff changeset
    86
    by (auto simp add: image_def Ball_def inj_on_def less_Suc_eq)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    87
  thus ?case by blast
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    88
qed
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    89
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    90
lemma nat_seg_image_imp_finite:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    91
  "A = f ` {i::nat. i < n} \<Longrightarrow> finite A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
    92
proof (induct n arbitrary: A)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    93
  case 0 thus ?case by simp
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    94
next
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    95
  case (Suc n)
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    96
  let ?B = "f ` {i. i < n}"
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    97
  have finB: "finite ?B" by(rule Suc.hyps[OF refl])
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    98
  show ?case
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
    99
  proof cases
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   100
    assume "\<exists>k<n. f n = f k"
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   101
    hence "A = ?B" using Suc.prems by(auto simp:less_Suc_eq)
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   102
    thus ?thesis using finB by simp
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   103
  next
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   104
    assume "\<not>(\<exists> k<n. f n = f k)"
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   105
    hence "A = insert (f n) ?B" using Suc.prems by(auto simp:less_Suc_eq)
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   106
    thus ?thesis using finB by simp
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   107
  qed
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   108
qed
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   109
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   110
lemma finite_conv_nat_seg_image:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   111
  "finite A \<longleftrightarrow> (\<exists>(n::nat) f. A = f ` {i::nat. i < n})"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   112
  by (blast intro: nat_seg_image_imp_finite dest: finite_imp_nat_seg_image_inj_on)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   113
32988
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   114
lemma finite_imp_inj_to_nat_seg:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   115
  assumes "finite A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   116
  shows "\<exists>f n::nat. f ` A = {i. i < n} \<and> inj_on f A"
32988
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   117
proof -
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   118
  from finite_imp_nat_seg_image_inj_on[OF `finite A`]
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   119
  obtain f and n::nat where bij: "bij_betw f {i. i<n} A"
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   120
    by (auto simp:bij_betw_def)
33057
764547b68538 inv_onto -> inv_into
nipkow
parents: 32989
diff changeset
   121
  let ?f = "the_inv_into {i. i<n} f"
32988
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   122
  have "inj_on ?f A & ?f ` A = {i. i<n}"
33057
764547b68538 inv_onto -> inv_into
nipkow
parents: 32989
diff changeset
   123
    by (fold bij_betw_def) (rule bij_betw_the_inv_into[OF bij])
32988
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   124
  thus ?thesis by blast
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   125
qed
d1d4d7a08a66 Inv -> inv_onto, inv abbr. inv_onto UNIV.
nipkow
parents: 32705
diff changeset
   126
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   127
lemma finite_Collect_less_nat [iff]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   128
  "finite {n::nat. n < k}"
44890
22f665a2e91c new fastforce replacing fastsimp - less confusing name
nipkow
parents: 44835
diff changeset
   129
  by (fastforce simp: finite_conv_nat_seg_image)
29920
b95f5b8b93dd more finiteness
nipkow
parents: 29918
diff changeset
   130
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   131
lemma finite_Collect_le_nat [iff]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   132
  "finite {n::nat. n \<le> k}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   133
  by (simp add: le_eq_less_or_eq Collect_disj_eq)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   134
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   135
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   136
subsubsection {* Finiteness and common set operations *}
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   137
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   138
lemma rev_finite_subset:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   139
  "finite B \<Longrightarrow> A \<subseteq> B \<Longrightarrow> finite A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   140
proof (induct arbitrary: A rule: finite_induct)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   141
  case empty
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   142
  then show ?case by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   143
next
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   144
  case (insert x F A)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   145
  have A: "A \<subseteq> insert x F" and r: "A - {x} \<subseteq> F \<Longrightarrow> finite (A - {x})" by fact+
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   146
  show "finite A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   147
  proof cases
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   148
    assume x: "x \<in> A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   149
    with A have "A - {x} \<subseteq> F" by (simp add: subset_insert_iff)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   150
    with r have "finite (A - {x})" .
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   151
    hence "finite (insert x (A - {x}))" ..
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   152
    also have "insert x (A - {x}) = A" using x by (rule insert_Diff)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   153
    finally show ?thesis .
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   154
  next
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   155
    show "A \<subseteq> F ==> ?thesis" by fact
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   156
    assume "x \<notin> A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   157
    with A show "A \<subseteq> F" by (simp add: subset_insert_iff)
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   158
  qed
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   159
qed
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   160
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   161
lemma finite_subset:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   162
  "A \<subseteq> B \<Longrightarrow> finite B \<Longrightarrow> finite A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   163
  by (rule rev_finite_subset)
29901
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   164
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   165
lemma finite_UnI:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   166
  assumes "finite F" and "finite G"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   167
  shows "finite (F \<union> G)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   168
  using assms by induct simp_all
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   169
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   170
lemma finite_Un [iff]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   171
  "finite (F \<union> G) \<longleftrightarrow> finite F \<and> finite G"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   172
  by (blast intro: finite_UnI finite_subset [of _ "F \<union> G"])
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   173
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   174
lemma finite_insert [simp]: "finite (insert a A) \<longleftrightarrow> finite A"
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   175
proof -
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   176
  have "finite {a} \<and> finite A \<longleftrightarrow> finite A" by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   177
  then have "finite ({a} \<union> A) \<longleftrightarrow> finite A" by (simp only: finite_Un)
23389
aaca6a8e5414 tuned proofs: avoid implicit prems;
wenzelm
parents: 23277
diff changeset
   178
  then show ?thesis by simp
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   179
qed
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   180
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   181
lemma finite_Int [simp, intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   182
  "finite F \<or> finite G \<Longrightarrow> finite (F \<inter> G)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   183
  by (blast intro: finite_subset)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   184
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   185
lemma finite_Collect_conjI [simp, intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   186
  "finite {x. P x} \<or> finite {x. Q x} \<Longrightarrow> finite {x. P x \<and> Q x}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   187
  by (simp add: Collect_conj_eq)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   188
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   189
lemma finite_Collect_disjI [simp]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   190
  "finite {x. P x \<or> Q x} \<longleftrightarrow> finite {x. P x} \<and> finite {x. Q x}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   191
  by (simp add: Collect_disj_eq)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   192
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   193
lemma finite_Diff [simp, intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   194
  "finite A \<Longrightarrow> finite (A - B)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   195
  by (rule finite_subset, rule Diff_subset)
29901
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   196
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   197
lemma finite_Diff2 [simp]:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   198
  assumes "finite B"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   199
  shows "finite (A - B) \<longleftrightarrow> finite A"
29901
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   200
proof -
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   201
  have "finite A \<longleftrightarrow> finite((A - B) \<union> (A \<inter> B))" by (simp add: Un_Diff_Int)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   202
  also have "\<dots> \<longleftrightarrow> finite (A - B)" using `finite B` by simp
29901
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   203
  finally show ?thesis ..
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   204
qed
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   205
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   206
lemma finite_Diff_insert [iff]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   207
  "finite (A - insert a B) \<longleftrightarrow> finite (A - B)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   208
proof -
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   209
  have "finite (A - B) \<longleftrightarrow> finite (A - B - {a})" by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   210
  moreover have "A - insert a B = A - B - {a}" by auto
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   211
  ultimately show ?thesis by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   212
qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   213
29901
f4b3f8fbf599 finiteness lemmas
nipkow
parents: 29879
diff changeset
   214
lemma finite_compl[simp]:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   215
  "finite (A :: 'a set) \<Longrightarrow> finite (- A) \<longleftrightarrow> finite (UNIV :: 'a set)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   216
  by (simp add: Compl_eq_Diff_UNIV)
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   217
29916
f24137b42d9b more finiteness
nipkow
parents: 29903
diff changeset
   218
lemma finite_Collect_not[simp]:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   219
  "finite {x :: 'a. P x} \<Longrightarrow> finite {x. \<not> P x} \<longleftrightarrow> finite (UNIV :: 'a set)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   220
  by (simp add: Collect_neg_eq)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   221
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   222
lemma finite_Union [simp, intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   223
  "finite A \<Longrightarrow> (\<And>M. M \<in> A \<Longrightarrow> finite M) \<Longrightarrow> finite(\<Union>A)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   224
  by (induct rule: finite_induct) simp_all
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   225
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   226
lemma finite_UN_I [intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   227
  "finite A \<Longrightarrow> (\<And>a. a \<in> A \<Longrightarrow> finite (B a)) \<Longrightarrow> finite (\<Union>a\<in>A. B a)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   228
  by (induct rule: finite_induct) simp_all
29903
2c0046b26f80 more finiteness changes
nipkow
parents: 29901
diff changeset
   229
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   230
lemma finite_UN [simp]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   231
  "finite A \<Longrightarrow> finite (UNION A B) \<longleftrightarrow> (\<forall>x\<in>A. finite (B x))"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   232
  by (blast intro: finite_subset)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   233
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   234
lemma finite_Inter [intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   235
  "\<exists>A\<in>M. finite A \<Longrightarrow> finite (\<Inter>M)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   236
  by (blast intro: Inter_lower finite_subset)
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   237
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   238
lemma finite_INT [intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   239
  "\<exists>x\<in>I. finite (A x) \<Longrightarrow> finite (\<Inter>x\<in>I. A x)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   240
  by (blast intro: INT_lower finite_subset)
13825
ef4c41e7956a new inverse image lemmas
paulson
parents: 13737
diff changeset
   241
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   242
lemma finite_imageI [simp, intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   243
  "finite F \<Longrightarrow> finite (h ` F)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   244
  by (induct rule: finite_induct) simp_all
13825
ef4c41e7956a new inverse image lemmas
paulson
parents: 13737
diff changeset
   245
31768
159cd6b5e5d4 lemma finite_image_set by Jeremy Avigad
haftmann
parents: 31465
diff changeset
   246
lemma finite_image_set [simp]:
159cd6b5e5d4 lemma finite_image_set by Jeremy Avigad
haftmann
parents: 31465
diff changeset
   247
  "finite {x. P x} \<Longrightarrow> finite { f x | x. P x }"
159cd6b5e5d4 lemma finite_image_set by Jeremy Avigad
haftmann
parents: 31465
diff changeset
   248
  by (simp add: image_Collect [symmetric])
159cd6b5e5d4 lemma finite_image_set by Jeremy Avigad
haftmann
parents: 31465
diff changeset
   249
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   250
lemma finite_imageD:
42206
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   251
  assumes "finite (f ` A)" and "inj_on f A"
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   252
  shows "finite A"
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   253
using assms
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   254
proof (induct "f ` A" arbitrary: A)
42206
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   255
  case empty then show ?case by simp
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   256
next
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   257
  case (insert x B)
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   258
  then have B_A: "insert x B = f ` A" by simp
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   259
  then obtain y where "x = f y" and "y \<in> A" by blast
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   260
  from B_A `x \<notin> B` have "B = f ` A - {x}" by blast
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   261
  with B_A `x \<notin> B` `x = f y` `inj_on f A` `y \<in> A` have "B = f ` (A - {y})" by (simp add: inj_on_image_set_diff)
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   262
  moreover from `inj_on f A` have "inj_on f (A - {y})" by (rule inj_on_diff)
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   263
  ultimately have "finite (A - {y})" by (rule insert.hyps)
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   264
  then show "finite A" by simp
0920f709610f tuned proof
haftmann
parents: 41988
diff changeset
   265
qed
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   266
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   267
lemma finite_surj:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   268
  "finite A \<Longrightarrow> B \<subseteq> f ` A \<Longrightarrow> finite B"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   269
  by (erule finite_subset) (rule finite_imageI)
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   270
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   271
lemma finite_range_imageI:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   272
  "finite (range g) \<Longrightarrow> finite (range (\<lambda>x. f (g x)))"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   273
  by (drule finite_imageI) (simp add: range_composition)
13825
ef4c41e7956a new inverse image lemmas
paulson
parents: 13737
diff changeset
   274
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   275
lemma finite_subset_image:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   276
  assumes "finite B"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   277
  shows "B \<subseteq> f ` A \<Longrightarrow> \<exists>C\<subseteq>A. finite C \<and> B = f ` C"
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   278
using assms
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   279
proof induct
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   280
  case empty then show ?case by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   281
next
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   282
  case insert then show ?case
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   283
    by (clarsimp simp del: image_insert simp add: image_insert [symmetric])
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   284
       blast
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   285
qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   286
43991
f4a7697011c5 finite vimage on arbitrary domains
hoelzl
parents: 43866
diff changeset
   287
lemma finite_vimage_IntI:
f4a7697011c5 finite vimage on arbitrary domains
hoelzl
parents: 43866
diff changeset
   288
  "finite F \<Longrightarrow> inj_on h A \<Longrightarrow> finite (h -` F \<inter> A)"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   289
  apply (induct rule: finite_induct)
21575
89463ae2612d tuned proofs;
wenzelm
parents: 21409
diff changeset
   290
   apply simp_all
14430
5cb24165a2e1 new material from Avigad, and simplified treatment of division by 0
paulson
parents: 14331
diff changeset
   291
  apply (subst vimage_insert)
43991
f4a7697011c5 finite vimage on arbitrary domains
hoelzl
parents: 43866
diff changeset
   292
  apply (simp add: finite_subset [OF inj_on_vimage_singleton] Int_Un_distrib2)
13825
ef4c41e7956a new inverse image lemmas
paulson
parents: 13737
diff changeset
   293
  done
ef4c41e7956a new inverse image lemmas
paulson
parents: 13737
diff changeset
   294
43991
f4a7697011c5 finite vimage on arbitrary domains
hoelzl
parents: 43866
diff changeset
   295
lemma finite_vimageI:
f4a7697011c5 finite vimage on arbitrary domains
hoelzl
parents: 43866
diff changeset
   296
  "finite F \<Longrightarrow> inj h \<Longrightarrow> finite (h -` F)"
f4a7697011c5 finite vimage on arbitrary domains
hoelzl
parents: 43866
diff changeset
   297
  using finite_vimage_IntI[of F h UNIV] by auto
f4a7697011c5 finite vimage on arbitrary domains
hoelzl
parents: 43866
diff changeset
   298
34111
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   299
lemma finite_vimageD:
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   300
  assumes fin: "finite (h -` F)" and surj: "surj h"
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   301
  shows "finite F"
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   302
proof -
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   303
  have "finite (h ` (h -` F))" using fin by (rule finite_imageI)
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   304
  also have "h ` (h -` F) = F" using surj by (rule surj_image_vimage_eq)
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   305
  finally show "finite F" .
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   306
qed
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   307
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   308
lemma finite_vimage_iff: "bij h \<Longrightarrow> finite (h -` F) \<longleftrightarrow> finite F"
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   309
  unfolding bij_def by (auto elim: finite_vimageD finite_vimageI)
1b015caba46c add lemmas rev_finite_subset, finite_vimageD, finite_vimage_iff
huffman
parents: 34007
diff changeset
   310
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   311
lemma finite_Collect_bex [simp]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   312
  assumes "finite A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   313
  shows "finite {x. \<exists>y\<in>A. Q x y} \<longleftrightarrow> (\<forall>y\<in>A. finite {x. Q x y})"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   314
proof -
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   315
  have "{x. \<exists>y\<in>A. Q x y} = (\<Union>y\<in>A. {x. Q x y})" by auto
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   316
  with assms show ?thesis by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   317
qed
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   318
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   319
lemma finite_Collect_bounded_ex [simp]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   320
  assumes "finite {y. P y}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   321
  shows "finite {x. \<exists>y. P y \<and> Q x y} \<longleftrightarrow> (\<forall>y. P y \<longrightarrow> finite {x. Q x y})"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   322
proof -
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   323
  have "{x. EX y. P y & Q x y} = (\<Union>y\<in>{y. P y}. {x. Q x y})" by auto
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   324
  with assms show ?thesis by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   325
qed
29920
b95f5b8b93dd more finiteness
nipkow
parents: 29918
diff changeset
   326
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   327
lemma finite_Plus:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   328
  "finite A \<Longrightarrow> finite B \<Longrightarrow> finite (A <+> B)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   329
  by (simp add: Plus_def)
17022
b257300c3a9c added Brian Hufmann's finite instances
nipkow
parents: 16775
diff changeset
   330
31080
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   331
lemma finite_PlusD: 
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   332
  fixes A :: "'a set" and B :: "'b set"
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   333
  assumes fin: "finite (A <+> B)"
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   334
  shows "finite A" "finite B"
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   335
proof -
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   336
  have "Inl ` A \<subseteq> A <+> B" by auto
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   337
  then have "finite (Inl ` A :: ('a + 'b) set)" using fin by (rule finite_subset)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   338
  then show "finite A" by (rule finite_imageD) (auto intro: inj_onI)
31080
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   339
next
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   340
  have "Inr ` B \<subseteq> A <+> B" by auto
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   341
  then have "finite (Inr ` B :: ('a + 'b) set)" using fin by (rule finite_subset)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   342
  then show "finite B" by (rule finite_imageD) (auto intro: inj_onI)
31080
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   343
qed
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   344
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   345
lemma finite_Plus_iff [simp]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   346
  "finite (A <+> B) \<longleftrightarrow> finite A \<and> finite B"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   347
  by (auto intro: finite_PlusD finite_Plus)
31080
21ffc770ebc0 lemmas by Andreas Lochbihler
nipkow
parents: 31017
diff changeset
   348
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   349
lemma finite_Plus_UNIV_iff [simp]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   350
  "finite (UNIV :: ('a + 'b) set) \<longleftrightarrow> finite (UNIV :: 'a set) \<and> finite (UNIV :: 'b set)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   351
  by (subst UNIV_Plus_UNIV [symmetric]) (rule finite_Plus_iff)
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   352
40786
0a54cfc9add3 gave more standard finite set rules simp and intro attribute
nipkow
parents: 40716
diff changeset
   353
lemma finite_SigmaI [simp, intro]:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   354
  "finite A \<Longrightarrow> (\<And>a. a\<in>A \<Longrightarrow> finite (B a)) ==> finite (SIGMA a:A. B a)"
40786
0a54cfc9add3 gave more standard finite set rules simp and intro attribute
nipkow
parents: 40716
diff changeset
   355
  by (unfold Sigma_def) blast
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   356
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   357
lemma finite_cartesian_product:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   358
  "finite A \<Longrightarrow> finite B \<Longrightarrow> finite (A \<times> B)"
15402
97204f3b4705 REorganized Finite_Set
nipkow
parents: 15392
diff changeset
   359
  by (rule finite_SigmaI)
97204f3b4705 REorganized Finite_Set
nipkow
parents: 15392
diff changeset
   360
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   361
lemma finite_Prod_UNIV:
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   362
  "finite (UNIV :: 'a set) \<Longrightarrow> finite (UNIV :: 'b set) \<Longrightarrow> finite (UNIV :: ('a \<times> 'b) set)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   363
  by (simp only: UNIV_Times_UNIV [symmetric] finite_cartesian_product)
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   364
15409
a063687d24eb new and stronger lemmas and improved simplification for finite sets
paulson
parents: 15402
diff changeset
   365
lemma finite_cartesian_productD1:
42207
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   366
  assumes "finite (A \<times> B)" and "B \<noteq> {}"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   367
  shows "finite A"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   368
proof -
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   369
  from assms obtain n f where "A \<times> B = f ` {i::nat. i < n}"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   370
    by (auto simp add: finite_conv_nat_seg_image)
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   371
  then have "fst ` (A \<times> B) = fst ` f ` {i::nat. i < n}" by simp
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   372
  with `B \<noteq> {}` have "A = (fst \<circ> f) ` {i::nat. i < n}"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   373
    by (simp add: image_compose)
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   374
  then have "\<exists>n f. A = f ` {i::nat. i < n}" by blast
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   375
  then show ?thesis
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   376
    by (auto simp add: finite_conv_nat_seg_image)
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   377
qed
15409
a063687d24eb new and stronger lemmas and improved simplification for finite sets
paulson
parents: 15402
diff changeset
   378
a063687d24eb new and stronger lemmas and improved simplification for finite sets
paulson
parents: 15402
diff changeset
   379
lemma finite_cartesian_productD2:
42207
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   380
  assumes "finite (A \<times> B)" and "A \<noteq> {}"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   381
  shows "finite B"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   382
proof -
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   383
  from assms obtain n f where "A \<times> B = f ` {i::nat. i < n}"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   384
    by (auto simp add: finite_conv_nat_seg_image)
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   385
  then have "snd ` (A \<times> B) = snd ` f ` {i::nat. i < n}" by simp
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   386
  with `A \<noteq> {}` have "B = (snd \<circ> f) ` {i::nat. i < n}"
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   387
    by (simp add: image_compose)
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   388
  then have "\<exists>n f. B = f ` {i::nat. i < n}" by blast
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   389
  then show ?thesis
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   390
    by (auto simp add: finite_conv_nat_seg_image)
2bda5eddadf3 tuned proofs
haftmann
parents: 42206
diff changeset
   391
qed
15409
a063687d24eb new and stronger lemmas and improved simplification for finite sets
paulson
parents: 15402
diff changeset
   392
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   393
lemma finite_Pow_iff [iff]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   394
  "finite (Pow A) \<longleftrightarrow> finite A"
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   395
proof
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   396
  assume "finite (Pow A)"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   397
  then have "finite ((%x. {x}) ` A)" by (blast intro: finite_subset)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   398
  then show "finite A" by (rule finite_imageD [unfolded inj_on_def]) simp
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   399
next
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   400
  assume "finite A"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   401
  then show "finite (Pow A)"
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
   402
    by induct (simp_all add: Pow_insert)
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   403
qed
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   404
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   405
corollary finite_Collect_subsets [simp, intro]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   406
  "finite A \<Longrightarrow> finite {B. B \<subseteq> A}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   407
  by (simp add: Pow_def [symmetric])
29918
214755b03df3 more finiteness
nipkow
parents: 29916
diff changeset
   408
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   409
lemma finite_UnionD: "finite(\<Union>A) \<Longrightarrow> finite A"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   410
  by (blast intro: finite_subset [OF subset_Pow_Union])
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   411
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   412
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   413
subsubsection {* Further induction rules on finite sets *}
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   414
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   415
lemma finite_ne_induct [case_names singleton insert, consumes 2]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   416
  assumes "finite F" and "F \<noteq> {}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   417
  assumes "\<And>x. P {x}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   418
    and "\<And>x F. finite F \<Longrightarrow> F \<noteq> {} \<Longrightarrow> x \<notin> F \<Longrightarrow> P F  \<Longrightarrow> P (insert x F)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   419
  shows "P F"
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   420
using assms
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   421
proof induct
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   422
  case empty then show ?case by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   423
next
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   424
  case (insert x F) then show ?case by cases auto
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   425
qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   426
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   427
lemma finite_subset_induct [consumes 2, case_names empty insert]:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   428
  assumes "finite F" and "F \<subseteq> A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   429
  assumes empty: "P {}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   430
    and insert: "\<And>a F. finite F \<Longrightarrow> a \<in> A \<Longrightarrow> a \<notin> F \<Longrightarrow> P F \<Longrightarrow> P (insert a F)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   431
  shows "P F"
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   432
using `finite F` `F \<subseteq> A`
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   433
proof induct
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   434
  show "P {}" by fact
31441
428e4caf2299 finite lemmas
nipkow
parents: 31438
diff changeset
   435
next
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   436
  fix x F
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   437
  assume "finite F" and "x \<notin> F" and
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   438
    P: "F \<subseteq> A \<Longrightarrow> P F" and i: "insert x F \<subseteq> A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   439
  show "P (insert x F)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   440
  proof (rule insert)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   441
    from i show "x \<in> A" by blast
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   442
    from i have "F \<subseteq> A" by blast
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   443
    with P show "P F" .
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   444
    show "finite F" by fact
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   445
    show "x \<notin> F" by fact
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   446
  qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   447
qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   448
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   449
lemma finite_empty_induct:
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   450
  assumes "finite A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   451
  assumes "P A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   452
    and remove: "\<And>a A. finite A \<Longrightarrow> a \<in> A \<Longrightarrow> P A \<Longrightarrow> P (A - {a})"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   453
  shows "P {}"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   454
proof -
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   455
  have "\<And>B. B \<subseteq> A \<Longrightarrow> P (A - B)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   456
  proof -
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   457
    fix B :: "'a set"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   458
    assume "B \<subseteq> A"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   459
    with `finite A` have "finite B" by (rule rev_finite_subset)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   460
    from this `B \<subseteq> A` show "P (A - B)"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   461
    proof induct
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   462
      case empty
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   463
      from `P A` show ?case by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   464
    next
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   465
      case (insert b B)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   466
      have "P (A - B - {b})"
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   467
      proof (rule remove)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   468
        from `finite A` show "finite (A - B)" by induct auto
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   469
        from insert show "b \<in> A - B" by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   470
        from insert show "P (A - B)" by simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   471
      qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   472
      also have "A - B - {b} = A - insert b B" by (rule Diff_insert [symmetric])
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   473
      finally show ?case .
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   474
    qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   475
  qed
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   476
  then have "P (A - A)" by blast
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   477
  then show ?thesis by simp
31441
428e4caf2299 finite lemmas
nipkow
parents: 31438
diff changeset
   478
qed
428e4caf2299 finite lemmas
nipkow
parents: 31438
diff changeset
   479
428e4caf2299 finite lemmas
nipkow
parents: 31438
diff changeset
   480
26441
7914697ff104 no "attach UNIV" any more
haftmann
parents: 26146
diff changeset
   481
subsection {* Class @{text finite}  *}
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   482
29797
08ef36ed2f8a handling type classes without parameters
haftmann
parents: 29675
diff changeset
   483
class finite =
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   484
  assumes finite_UNIV: "finite (UNIV \<Colon> 'a set)"
27430
1e25ac05cd87 prove lemma finite in context of finite class
huffman
parents: 27418
diff changeset
   485
begin
1e25ac05cd87 prove lemma finite in context of finite class
huffman
parents: 27418
diff changeset
   486
1e25ac05cd87 prove lemma finite in context of finite class
huffman
parents: 27418
diff changeset
   487
lemma finite [simp]: "finite (A \<Colon> 'a set)"
26441
7914697ff104 no "attach UNIV" any more
haftmann
parents: 26146
diff changeset
   488
  by (rule subset_UNIV finite_UNIV finite_subset)+
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   489
43866
8a50dc70cbff moving UNIV = ... equations to their proper theories
haftmann
parents: 42875
diff changeset
   490
lemma finite_code [code]: "finite (A \<Colon> 'a set) \<longleftrightarrow> True"
40922
4d0f96a54e76 adding code equation for finiteness of finite types
bulwahn
parents: 40786
diff changeset
   491
  by simp
4d0f96a54e76 adding code equation for finiteness of finite types
bulwahn
parents: 40786
diff changeset
   492
27430
1e25ac05cd87 prove lemma finite in context of finite class
huffman
parents: 27418
diff changeset
   493
end
1e25ac05cd87 prove lemma finite in context of finite class
huffman
parents: 27418
diff changeset
   494
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   495
instance prod :: (finite, finite) finite
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   496
  by default (simp only: UNIV_Times_UNIV [symmetric] finite_cartesian_product finite)
26146
61cb176d0385 tuned proofs
haftmann
parents: 26041
diff changeset
   497
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   498
lemma inj_graph: "inj (%f. {(x, y). y = f x})"
39302
d7728f65b353 renamed lemmas: ext_iff -> fun_eq_iff, set_ext_iff -> set_eq_iff, set_ext -> set_eqI
nipkow
parents: 39198
diff changeset
   499
  by (rule inj_onI, auto simp add: set_eq_iff fun_eq_iff)
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   500
26146
61cb176d0385 tuned proofs
haftmann
parents: 26041
diff changeset
   501
instance "fun" :: (finite, finite) finite
61cb176d0385 tuned proofs
haftmann
parents: 26041
diff changeset
   502
proof
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   503
  show "finite (UNIV :: ('a => 'b) set)"
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   504
  proof (rule finite_imageD)
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   505
    let ?graph = "%f::'a => 'b. {(x, y). y = f x}"
26792
f2d75fd23124 - Deleted code setup for finite and card
berghofe
parents: 26757
diff changeset
   506
    have "range ?graph \<subseteq> Pow UNIV" by simp
f2d75fd23124 - Deleted code setup for finite and card
berghofe
parents: 26757
diff changeset
   507
    moreover have "finite (Pow (UNIV :: ('a * 'b) set))"
f2d75fd23124 - Deleted code setup for finite and card
berghofe
parents: 26757
diff changeset
   508
      by (simp only: finite_Pow_iff finite)
f2d75fd23124 - Deleted code setup for finite and card
berghofe
parents: 26757
diff changeset
   509
    ultimately show "finite (range ?graph)"
f2d75fd23124 - Deleted code setup for finite and card
berghofe
parents: 26757
diff changeset
   510
      by (rule finite_subset)
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   511
    show "inj ?graph" by (rule inj_graph)
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   512
  qed
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   513
qed
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   514
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   515
instance bool :: finite
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   516
  by default (simp add: UNIV_bool)
44831
haftmann
parents: 43991
diff changeset
   517
45962
fc77947a7db4 finite type class instance for `set`
haftmann
parents: 45166
diff changeset
   518
instance set :: (finite) finite
fc77947a7db4 finite type class instance for `set`
haftmann
parents: 45166
diff changeset
   519
  by default (simp only: Pow_UNIV [symmetric] finite_Pow_iff finite)
fc77947a7db4 finite type class instance for `set`
haftmann
parents: 45166
diff changeset
   520
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   521
instance unit :: finite
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   522
  by default (simp add: UNIV_unit)
44831
haftmann
parents: 43991
diff changeset
   523
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   524
instance sum :: (finite, finite) finite
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   525
  by default (simp only: UNIV_Plus_UNIV [symmetric] finite_Plus finite)
27981
feb0c01cf0fb tuned import order
haftmann
parents: 27611
diff changeset
   526
44831
haftmann
parents: 43991
diff changeset
   527
lemma finite_option_UNIV [simp]:
haftmann
parents: 43991
diff changeset
   528
  "finite (UNIV :: 'a option set) = finite (UNIV :: 'a set)"
haftmann
parents: 43991
diff changeset
   529
  by (auto simp add: UNIV_option_conv elim: finite_imageD intro: inj_Some)
haftmann
parents: 43991
diff changeset
   530
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   531
instance option :: (finite) finite
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   532
  by default (simp add: UNIV_option_conv)
44831
haftmann
parents: 43991
diff changeset
   533
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   534
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   535
subsection {* A basic fold functional for finite sets *}
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   536
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   537
text {* The intended behaviour is
31916
f3227bb306a4 recovered subscripts, which were lost in b41d61c768e2 (due to Emacs accident?);
wenzelm
parents: 31907
diff changeset
   538
@{text "fold f z {x\<^isub>1, ..., x\<^isub>n} = f x\<^isub>1 (\<dots> (f x\<^isub>n z)\<dots>)"}
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   539
if @{text f} is ``left-commutative'':
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   540
*}
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   541
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   542
locale comp_fun_commute =
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   543
  fixes f :: "'a \<Rightarrow> 'b \<Rightarrow> 'b"
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   544
  assumes comp_fun_commute: "f y \<circ> f x = f x \<circ> f y"
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   545
begin
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   546
42809
5b45125b15ba use pointfree characterisation for fold_set locale
haftmann
parents: 42715
diff changeset
   547
lemma fun_left_comm: "f x (f y z) = f y (f x z)"
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   548
  using comp_fun_commute by (simp add: fun_eq_iff)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   549
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   550
end
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   551
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   552
inductive fold_graph :: "('a \<Rightarrow> 'b \<Rightarrow> 'b) \<Rightarrow> 'b \<Rightarrow> 'a set \<Rightarrow> 'b \<Rightarrow> bool"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   553
for f :: "'a \<Rightarrow> 'b \<Rightarrow> 'b" and z :: 'b where
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   554
  emptyI [intro]: "fold_graph f z {} z" |
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   555
  insertI [intro]: "x \<notin> A \<Longrightarrow> fold_graph f z A y
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   556
      \<Longrightarrow> fold_graph f z (insert x A) (f x y)"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   557
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   558
inductive_cases empty_fold_graphE [elim!]: "fold_graph f z {} x"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   559
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   560
definition fold :: "('a \<Rightarrow> 'b \<Rightarrow> 'b) \<Rightarrow> 'b \<Rightarrow> 'a set \<Rightarrow> 'b" where
37767
a2b7a20d6ea3 dropped superfluous [code del]s
haftmann
parents: 37678
diff changeset
   561
  "fold f z A = (THE y. fold_graph f z A y)"
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   562
15498
3988e90613d4 comment
paulson
parents: 15497
diff changeset
   563
text{*A tempting alternative for the definiens is
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   564
@{term "if finite A then THE y. fold_graph f z A y else e"}.
15498
3988e90613d4 comment
paulson
parents: 15497
diff changeset
   565
It allows the removal of finiteness assumptions from the theorems
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   566
@{text fold_comm}, @{text fold_reindex} and @{text fold_distrib}.
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   567
The proofs become ugly. It is not worth the effort. (???) *}
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   568
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   569
lemma finite_imp_fold_graph: "finite A \<Longrightarrow> \<exists>x. fold_graph f z A x"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   570
by (induct rule: finite_induct) auto
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   571
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   572
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   573
subsubsection{*From @{const fold_graph} to @{term fold}*}
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   574
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   575
context comp_fun_commute
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   576
begin
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   577
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   578
lemma fold_graph_insertE_aux:
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   579
  "fold_graph f z A y \<Longrightarrow> a \<in> A \<Longrightarrow> \<exists>y'. y = f a y' \<and> fold_graph f z (A - {a}) y'"
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   580
proof (induct set: fold_graph)
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   581
  case (insertI x A y) show ?case
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   582
  proof (cases "x = a")
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   583
    assume "x = a" with insertI show ?case by auto
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   584
  next
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   585
    assume "x \<noteq> a"
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   586
    then obtain y' where y: "y = f a y'" and y': "fold_graph f z (A - {a}) y'"
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   587
      using insertI by auto
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   588
    have "f x y = f a (f x y')"
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   589
      unfolding y by (rule fun_left_comm)
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   590
    moreover have "fold_graph f z (insert x A - {a}) (f x y')"
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   591
      using y' and `x \<noteq> a` and `x \<notin> A`
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   592
      by (simp add: insert_Diff_if fold_graph.insertI)
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   593
    ultimately show ?case by fast
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   594
  qed
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   595
qed simp
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   596
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   597
lemma fold_graph_insertE:
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   598
  assumes "fold_graph f z (insert x A) v" and "x \<notin> A"
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   599
  obtains y where "v = f x y" and "fold_graph f z A y"
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   600
using assms by (auto dest: fold_graph_insertE_aux [OF _ insertI1])
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   601
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   602
lemma fold_graph_determ:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   603
  "fold_graph f z A x \<Longrightarrow> fold_graph f z A y \<Longrightarrow> y = x"
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   604
proof (induct arbitrary: y set: fold_graph)
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   605
  case (insertI x A y v)
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   606
  from `fold_graph f z (insert x A) v` and `x \<notin> A`
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   607
  obtain y' where "v = f x y'" and "fold_graph f z A y'"
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   608
    by (rule fold_graph_insertE)
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   609
  from `fold_graph f z A y'` have "y' = y" by (rule insertI)
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   610
  with `v = f x y'` show "v = f x y" by simp
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   611
qed fast
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   612
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   613
lemma fold_equality:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   614
  "fold_graph f z A y \<Longrightarrow> fold f z A = y"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   615
by (unfold fold_def) (blast intro: fold_graph_determ)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   616
42272
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   617
lemma fold_graph_fold:
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   618
  assumes "finite A"
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   619
  shows "fold_graph f z A (fold f z A)"
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   620
proof -
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   621
  from assms have "\<exists>x. fold_graph f z A x" by (rule finite_imp_fold_graph)
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   622
  moreover note fold_graph_determ
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   623
  ultimately have "\<exists>!x. fold_graph f z A x" by (rule ex_ex1I)
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   624
  then have "fold_graph f z A (The (fold_graph f z A))" by (rule theI')
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   625
  then show ?thesis by (unfold fold_def)
a46a13b4be5f dropped unused lemmas; proper Isar proof
haftmann
parents: 42207
diff changeset
   626
qed
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
   627
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   628
text{* The base case for @{text fold}: *}
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   629
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   630
lemma (in -) fold_empty [simp]: "fold f z {} = z"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   631
by (unfold fold_def) blast
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   632
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   633
text{* The various recursion equations for @{const fold}: *}
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   634
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   635
lemma fold_insert [simp]:
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   636
  assumes "finite A" and "x \<notin> A"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   637
  shows "fold f z (insert x A) = f x (fold f z A)"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   638
proof (rule fold_equality)
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   639
  from `finite A` have "fold_graph f z A (fold f z A)" by (rule fold_graph_fold)
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   640
  with `x \<notin> A`show "fold_graph f z (insert x A) (f x (fold f z A))" by (rule fold_graph.insertI)
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   641
qed
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   642
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   643
lemma fold_fun_comm:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   644
  "finite A \<Longrightarrow> f x (fold f z A) = fold f (f x z) A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   645
proof (induct rule: finite_induct)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   646
  case empty then show ?case by simp
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   647
next
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   648
  case (insert y A) then show ?case
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   649
    by (simp add: fun_left_comm[of x])
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   650
qed
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   651
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   652
lemma fold_insert2:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   653
  "finite A \<Longrightarrow> x \<notin> A \<Longrightarrow> fold f z (insert x A) = fold f (f x z) A"
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
   654
by (simp add: fold_fun_comm)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   655
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   656
lemma fold_rec:
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   657
  assumes "finite A" and "x \<in> A"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   658
  shows "fold f z A = f x (fold f z (A - {x}))"
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   659
proof -
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   660
  have A: "A = insert x (A - {x})" using `x \<in> A` by blast
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   661
  then have "fold f z A = fold f z (insert x (A - {x}))" by simp
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   662
  also have "\<dots> = f x (fold f z (A - {x}))"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   663
    by (rule fold_insert) (simp add: `finite A`)+
15535
nipkow
parents: 15532
diff changeset
   664
  finally show ?thesis .
nipkow
parents: 15532
diff changeset
   665
qed
nipkow
parents: 15532
diff changeset
   666
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   667
lemma fold_insert_remove:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   668
  assumes "finite A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   669
  shows "fold f z (insert x A) = f x (fold f z (A - {x}))"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   670
proof -
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   671
  from `finite A` have "finite (insert x A)" by auto
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   672
  moreover have "x \<in> insert x A" by auto
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   673
  ultimately have "fold f z (insert x A) = f x (fold f z (insert x A - {x}))"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   674
    by (rule fold_rec)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   675
  then show ?thesis by simp
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   676
qed
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   677
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   678
end
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   679
15480
cb3612cc41a3 renamed a few vars, added a lemma
nipkow
parents: 15479
diff changeset
   680
text{* A simplified version for idempotent functions: *}
cb3612cc41a3 renamed a few vars, added a lemma
nipkow
parents: 15479
diff changeset
   681
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   682
locale comp_fun_idem = comp_fun_commute +
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   683
  assumes comp_fun_idem: "f x o f x = f x"
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   684
begin
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   685
42869
43b0f61f56d0 use point-free characterization for locale fun_left_comm_idem
haftmann
parents: 42809
diff changeset
   686
lemma fun_left_idem: "f x (f x z) = f x z"
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   687
  using comp_fun_idem by (simp add: fun_eq_iff)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   688
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   689
lemma fold_insert_idem:
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   690
  assumes fin: "finite A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   691
  shows "fold f z (insert x A) = f x (fold f z A)"
15480
cb3612cc41a3 renamed a few vars, added a lemma
nipkow
parents: 15479
diff changeset
   692
proof cases
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   693
  assume "x \<in> A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   694
  then obtain B where "A = insert x B" and "x \<notin> B" by (rule set_insert)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   695
  then show ?thesis using assms by (simp add:fun_left_idem)
15480
cb3612cc41a3 renamed a few vars, added a lemma
nipkow
parents: 15479
diff changeset
   696
next
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   697
  assume "x \<notin> A" then show ?thesis using assms by simp
15480
cb3612cc41a3 renamed a few vars, added a lemma
nipkow
parents: 15479
diff changeset
   698
qed
cb3612cc41a3 renamed a few vars, added a lemma
nipkow
parents: 15479
diff changeset
   699
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   700
declare fold_insert[simp del] fold_insert_idem[simp]
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   701
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   702
lemma fold_insert_idem2:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   703
  "finite A \<Longrightarrow> fold f z (insert x A) = fold f (f x z) A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   704
by(simp add:fold_fun_comm)
15484
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
   705
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   706
end
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   707
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   708
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   709
subsubsection {* Expressing set operations via @{const fold} *}
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   710
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   711
lemma (in comp_fun_commute) comp_comp_fun_commute:
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   712
  "comp_fun_commute (f \<circ> g)"
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   713
proof
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   714
qed (simp_all add: comp_fun_commute)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   715
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   716
lemma (in comp_fun_idem) comp_comp_fun_idem:
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   717
  "comp_fun_idem (f \<circ> g)"
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   718
  by (rule comp_fun_idem.intro, rule comp_comp_fun_commute, unfold_locales)
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   719
    (simp_all add: comp_fun_idem)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   720
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   721
lemma comp_fun_idem_insert:
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   722
  "comp_fun_idem insert"
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   723
proof
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   724
qed auto
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   725
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   726
lemma comp_fun_idem_remove:
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   727
  "comp_fun_idem Set.remove"
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   728
proof
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   729
qed auto
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   730
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   731
lemma (in semilattice_inf) comp_fun_idem_inf:
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   732
  "comp_fun_idem inf"
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   733
proof
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   734
qed (auto simp add: inf_left_commute)
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   735
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   736
lemma (in semilattice_sup) comp_fun_idem_sup:
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   737
  "comp_fun_idem sup"
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   738
proof
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   739
qed (auto simp add: sup_left_commute)
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   740
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   741
lemma union_fold_insert:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   742
  assumes "finite A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   743
  shows "A \<union> B = fold insert B A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   744
proof -
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   745
  interpret comp_fun_idem insert by (fact comp_fun_idem_insert)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   746
  from `finite A` show ?thesis by (induct A arbitrary: B) simp_all
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   747
qed
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   748
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   749
lemma minus_fold_remove:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   750
  assumes "finite A"
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   751
  shows "B - A = fold Set.remove B A"
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   752
proof -
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   753
  interpret comp_fun_idem Set.remove by (fact comp_fun_idem_remove)
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   754
  from `finite A` have "fold Set.remove B A = B - A" by (induct A arbitrary: B) auto
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   755
  then show ?thesis ..
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   756
qed
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   757
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   758
context complete_lattice
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   759
begin
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   760
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   761
lemma inf_Inf_fold_inf:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   762
  assumes "finite A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   763
  shows "inf B (Inf A) = fold inf B A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   764
proof -
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   765
  interpret comp_fun_idem inf by (fact comp_fun_idem_inf)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   766
  from `finite A` show ?thesis by (induct A arbitrary: B)
44919
482f1807976e tune proofs
noschinl
parents: 44890
diff changeset
   767
    (simp_all add: inf_commute fold_fun_comm)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   768
qed
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   769
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   770
lemma sup_Sup_fold_sup:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   771
  assumes "finite A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   772
  shows "sup B (Sup A) = fold sup B A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   773
proof -
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   774
  interpret comp_fun_idem sup by (fact comp_fun_idem_sup)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   775
  from `finite A` show ?thesis by (induct A arbitrary: B)
44919
482f1807976e tune proofs
noschinl
parents: 44890
diff changeset
   776
    (simp_all add: sup_commute fold_fun_comm)
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   777
qed
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   778
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   779
lemma Inf_fold_inf:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   780
  assumes "finite A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   781
  shows "Inf A = fold inf top A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   782
  using assms inf_Inf_fold_inf [of A top] by (simp add: inf_absorb2)
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   783
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   784
lemma Sup_fold_sup:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   785
  assumes "finite A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   786
  shows "Sup A = fold sup bot A"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   787
  using assms sup_Sup_fold_sup [of A bot] by (simp add: sup_absorb2)
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   788
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   789
lemma inf_INF_fold_inf:
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   790
  assumes "finite A"
42873
da1253ff1764 point-free characterization of operations on finite sets
haftmann
parents: 42871
diff changeset
   791
  shows "inf B (INFI A f) = fold (inf \<circ> f) B A" (is "?inf = ?fold") 
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   792
proof (rule sym)
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   793
  interpret comp_fun_idem inf by (fact comp_fun_idem_inf)
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   794
  interpret comp_fun_idem "inf \<circ> f" by (fact comp_comp_fun_idem)
42873
da1253ff1764 point-free characterization of operations on finite sets
haftmann
parents: 42871
diff changeset
   795
  from `finite A` show "?fold = ?inf"
42869
43b0f61f56d0 use point-free characterization for locale fun_left_comm_idem
haftmann
parents: 42809
diff changeset
   796
    by (induct A arbitrary: B)
44928
7ef6505bde7f renamed Complete_Lattices lemmas, removed legacy names
hoelzl
parents: 44919
diff changeset
   797
      (simp_all add: INF_def inf_left_commute)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   798
qed
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   799
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   800
lemma sup_SUP_fold_sup:
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   801
  assumes "finite A"
42873
da1253ff1764 point-free characterization of operations on finite sets
haftmann
parents: 42871
diff changeset
   802
  shows "sup B (SUPR A f) = fold (sup \<circ> f) B A" (is "?sup = ?fold") 
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   803
proof (rule sym)
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   804
  interpret comp_fun_idem sup by (fact comp_fun_idem_sup)
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
   805
  interpret comp_fun_idem "sup \<circ> f" by (fact comp_comp_fun_idem)
42873
da1253ff1764 point-free characterization of operations on finite sets
haftmann
parents: 42871
diff changeset
   806
  from `finite A` show "?fold = ?sup"
42869
43b0f61f56d0 use point-free characterization for locale fun_left_comm_idem
haftmann
parents: 42809
diff changeset
   807
    by (induct A arbitrary: B)
44928
7ef6505bde7f renamed Complete_Lattices lemmas, removed legacy names
hoelzl
parents: 44919
diff changeset
   808
      (simp_all add: SUP_def sup_left_commute)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   809
qed
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   810
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   811
lemma INF_fold_inf:
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   812
  assumes "finite A"
42873
da1253ff1764 point-free characterization of operations on finite sets
haftmann
parents: 42871
diff changeset
   813
  shows "INFI A f = fold (inf \<circ> f) top A"
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   814
  using assms inf_INF_fold_inf [of A top] by simp
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   815
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   816
lemma SUP_fold_sup:
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   817
  assumes "finite A"
42873
da1253ff1764 point-free characterization of operations on finite sets
haftmann
parents: 42871
diff changeset
   818
  shows "SUPR A f = fold (sup \<circ> f) bot A"
46146
6baea4fca6bd incorporated various theorems from theory More_Set into corpus
haftmann
parents: 46033
diff changeset
   819
  using assms sup_SUP_fold_sup [of A bot] by simp
31992
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   820
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   821
end
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   822
f8aed98faae7 More about gcd/lcm, and some cleaning up
nipkow
parents: 31916
diff changeset
   823
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   824
subsection {* The derived combinator @{text fold_image} *}
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   825
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   826
definition fold_image :: "('b \<Rightarrow> 'b \<Rightarrow> 'b) \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> 'b \<Rightarrow> 'a set \<Rightarrow> 'b"
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   827
  where "fold_image f g = fold (\<lambda>x y. f (g x) y)"
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   828
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   829
lemma fold_image_empty[simp]: "fold_image f g z {} = z"
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   830
  by (simp add:fold_image_def)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   831
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   832
context ab_semigroup_mult
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   833
begin
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   834
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   835
lemma fold_image_insert[simp]:
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   836
  assumes "finite A" and "a \<notin> A"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   837
  shows "fold_image times g z (insert a A) = g a * (fold_image times g z A)"
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   838
proof -
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   839
  interpret comp_fun_commute "%x y. (g x) * y"
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   840
    by default (simp add: fun_eq_iff mult_ac)
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
   841
  from assms show ?thesis by (simp add: fold_image_def)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   842
qed
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   843
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   844
lemma fold_image_reindex:
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   845
  assumes "finite A"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   846
  shows "inj_on h A \<Longrightarrow> fold_image times g z (h ` A) = fold_image times (g \<circ> h) z A"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   847
  using assms by induct auto
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   848
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   849
lemma fold_image_cong:
42875
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   850
  assumes "finite A" and g_h: "\<And>x. x\<in>A \<Longrightarrow> g x = h x"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   851
  shows "fold_image times g z A = fold_image times h z A"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   852
proof -
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   853
  from `finite A`
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   854
  have "\<And>C. C <= A --> (ALL x:C. g x = h x) --> fold_image times g z C = fold_image times h z C"
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   855
  proof (induct arbitrary: C)
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   856
    case empty then show ?case by simp
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   857
  next
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   858
    case (insert x F) then show ?case apply -
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   859
    apply (simp add: subset_insert_iff, clarify)
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   860
    apply (subgoal_tac "finite C")
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   861
      prefer 2 apply (blast dest: finite_subset [COMP swap_prems_rl])
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   862
    apply (subgoal_tac "C = insert x (C - {x})")
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   863
      prefer 2 apply blast
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   864
    apply (erule ssubst)
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   865
    apply (simp add: Ball_def del: insert_Diff_single)
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   866
    done
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   867
  qed
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   868
  with g_h show ?thesis by simp
d1aad0957eb2 tuned proofs
haftmann
parents: 42873
diff changeset
   869
qed
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   870
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   871
end
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   872
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   873
context comm_monoid_mult
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   874
begin
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   875
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   876
lemma fold_image_1:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   877
  "finite S \<Longrightarrow> (\<forall>x\<in>S. f x = 1) \<Longrightarrow> fold_image op * f 1 S = 1"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   878
  apply (induct rule: finite_induct)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   879
  apply simp by auto
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   880
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   881
lemma fold_image_Un_Int:
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   882
  "finite A ==> finite B ==>
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   883
    fold_image times g 1 A * fold_image times g 1 B =
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   884
    fold_image times g 1 (A Un B) * fold_image times g 1 (A Int B)"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   885
  apply (induct rule: finite_induct)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   886
by (induct set: finite) 
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   887
   (auto simp add: mult_ac insert_absorb Int_insert_left)
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   888
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   889
lemma fold_image_Un_one:
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   890
  assumes fS: "finite S" and fT: "finite T"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   891
  and I0: "\<forall>x \<in> S\<inter>T. f x = 1"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   892
  shows "fold_image (op *) f 1 (S \<union> T) = fold_image (op *) f 1 S * fold_image (op *) f 1 T"
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   893
proof-
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   894
  have "fold_image op * f 1 (S \<inter> T) = 1" 
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   895
    apply (rule fold_image_1)
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   896
    using fS fT I0 by auto 
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   897
  with fold_image_Un_Int[OF fS fT] show ?thesis by simp
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   898
qed
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   899
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   900
corollary fold_Un_disjoint:
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   901
  "finite A ==> finite B ==> A Int B = {} ==>
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   902
   fold_image times g 1 (A Un B) =
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   903
   fold_image times g 1 A * fold_image times g 1 B"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   904
by (simp add: fold_image_Un_Int)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   905
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   906
lemma fold_image_UN_disjoint:
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   907
  "\<lbrakk> finite I; ALL i:I. finite (A i);
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   908
     ALL i:I. ALL j:I. i \<noteq> j --> A i Int A j = {} \<rbrakk>
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   909
   \<Longrightarrow> fold_image times g 1 (UNION I A) =
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   910
       fold_image times (%i. fold_image times g 1 (A i)) 1 I"
41656
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   911
apply (induct rule: finite_induct)
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   912
apply simp
011fcb70e32f restructured theory;
haftmann
parents: 41550
diff changeset
   913
apply atomize
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   914
apply (subgoal_tac "ALL i:F. x \<noteq> i")
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   915
 prefer 2 apply blast
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   916
apply (subgoal_tac "A x Int UNION F A = {}")
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   917
 prefer 2 apply blast
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   918
apply (simp add: fold_Un_disjoint)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   919
done
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   920
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   921
lemma fold_image_Sigma: "finite A ==> ALL x:A. finite (B x) ==>
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   922
  fold_image times (%x. fold_image times (g x) 1 (B x)) 1 A =
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   923
  fold_image times (split g) 1 (SIGMA x:A. B x)"
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   924
apply (subst Sigma_def)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   925
apply (subst fold_image_UN_disjoint, assumption, simp)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   926
 apply blast
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   927
apply (erule fold_image_cong)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   928
apply (subst fold_image_UN_disjoint, simp, simp)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   929
 apply blast
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
   930
apply simp
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   931
done
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   932
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   933
lemma fold_image_distrib: "finite A \<Longrightarrow>
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   934
   fold_image times (%x. g x * h x) 1 A =
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   935
   fold_image times g 1 A *  fold_image times h 1 A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   936
by (erule finite_induct) (simp_all add: mult_ac)
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   937
30260
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   938
lemma fold_image_related: 
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   939
  assumes Re: "R e e" 
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   940
  and Rop: "\<forall>x1 y1 x2 y2. R x1 x2 \<and> R y1 y2 \<longrightarrow> R (x1 * y1) (x2 * y2)" 
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   941
  and fS: "finite S" and Rfg: "\<forall>x\<in>S. R (h x) (g x)"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   942
  shows "R (fold_image (op *) h e S) (fold_image (op *) g e S)"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   943
  using fS by (rule finite_subset_induct) (insert assms, auto)
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   944
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   945
lemma  fold_image_eq_general:
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   946
  assumes fS: "finite S"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   947
  and h: "\<forall>y\<in>S'. \<exists>!x. x\<in> S \<and> h(x) = y" 
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   948
  and f12:  "\<forall>x\<in>S. h x \<in> S' \<and> f2(h x) = f1 x"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   949
  shows "fold_image (op *) f1 e S = fold_image (op *) f2 e S'"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   950
proof-
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   951
  from h f12 have hS: "h ` S = S'" by auto
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   952
  {fix x y assume H: "x \<in> S" "y \<in> S" "h x = h y"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   953
    from f12 h H  have "x = y" by auto }
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   954
  hence hinj: "inj_on h S" unfolding inj_on_def Ex1_def by blast
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   955
  from f12 have th: "\<And>x. x \<in> S \<Longrightarrow> (f2 \<circ> h) x = f1 x" by auto 
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   956
  from hS have "fold_image (op *) f2 e S' = fold_image (op *) f2 e (h ` S)" by simp
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   957
  also have "\<dots> = fold_image (op *) (f2 o h) e S" 
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   958
    using fold_image_reindex[OF fS hinj, of f2 e] .
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   959
  also have "\<dots> = fold_image (op *) f1 e S " using th fold_image_cong[OF fS, of "f2 o h" f1 e]
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   960
    by blast
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   961
  finally show ?thesis ..
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   962
qed
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   963
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   964
lemma fold_image_eq_general_inverses:
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   965
  assumes fS: "finite S" 
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   966
  and kh: "\<And>y. y \<in> T \<Longrightarrow> k y \<in> S \<and> h (k y) = y"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   967
  and hk: "\<And>x. x \<in> S \<Longrightarrow> h x \<in> T \<and> k (h x) = x  \<and> g (h x) = f x"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   968
  shows "fold_image (op *) f e S = fold_image (op *) g e T"
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   969
  (* metis solves it, but not yet available here *)
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   970
  apply (rule fold_image_eq_general[OF fS, of T h g f e])
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   971
  apply (rule ballI)
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   972
  apply (frule kh)
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   973
  apply (rule ex1I[])
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   974
  apply blast
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   975
  apply clarsimp
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   976
  apply (drule hk) apply simp
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   977
  apply (rule sym)
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   978
  apply (erule conjunct1[OF conjunct2[OF hk]])
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   979
  apply (rule ballI)
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   980
  apply (drule  hk)
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   981
  apply blast
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   982
  done
be39acd3ac85 Added general theorems for fold_image, setsum and set_prod
chaieb
parents: 29966
diff changeset
   983
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
   984
end
22917
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
   985
25162
ad4d5365d9d8 went back to >0
nipkow
parents: 25062
diff changeset
   986
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
   987
subsection {* A fold functional for non-empty sets *}
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   988
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
   989
text{* Does not require start value. *}
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   990
23736
bf8d4a46452d Renamed inductive2 to inductive.
berghofe
parents: 23706
diff changeset
   991
inductive
22262
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
   992
  fold1Set :: "('a => 'a => 'a) => 'a set => 'a => bool"
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
   993
  for f :: "'a => 'a => 'a"
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
   994
where
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
   995
  fold1Set_insertI [intro]:
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
   996
   "\<lbrakk> fold_graph f a A x; a \<notin> A \<rbrakk> \<Longrightarrow> fold1Set f (insert a A) x"
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
   997
35416
d8d7d1b785af replaced a couple of constsdefs by definitions (also some old primrecs by modern ones)
haftmann
parents: 35267
diff changeset
   998
definition fold1 :: "('a => 'a => 'a) => 'a set => 'a" where
22262
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
   999
  "fold1 f A == THE x. fold1Set f A x"
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1000
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1001
lemma fold1Set_nonempty:
22917
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1002
  "fold1Set f A x \<Longrightarrow> A \<noteq> {}"
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1003
by(erule fold1Set.cases, simp_all)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
  1004
23736
bf8d4a46452d Renamed inductive2 to inductive.
berghofe
parents: 23706
diff changeset
  1005
inductive_cases empty_fold1SetE [elim!]: "fold1Set f {} x"
bf8d4a46452d Renamed inductive2 to inductive.
berghofe
parents: 23706
diff changeset
  1006
bf8d4a46452d Renamed inductive2 to inductive.
berghofe
parents: 23706
diff changeset
  1007
inductive_cases insert_fold1SetE [elim!]: "fold1Set f (insert a X) x"
22262
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
  1008
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
  1009
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
  1010
lemma fold1Set_sing [iff]: "(fold1Set f {a} b) = (a = b)"
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
  1011
by (blast elim: fold_graph.cases)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
  1012
22917
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1013
lemma fold1_singleton [simp]: "fold1 f {a} = a"
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1014
by (unfold fold1_def) blast
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
  1015
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1016
lemma finite_nonempty_imp_fold1Set:
22262
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
  1017
  "\<lbrakk> finite A; A \<noteq> {} \<rbrakk> \<Longrightarrow> EX x. fold1Set f A x"
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1018
apply (induct A rule: finite_induct)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1019
apply (auto dest: finite_imp_fold_graph [of _ f])
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1020
done
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1021
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1022
text{*First, some lemmas about @{const fold_graph}.*}
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
  1023
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1024
context ab_semigroup_mult
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1025
begin
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1026
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
  1027
lemma comp_fun_commute: "comp_fun_commute (op *)"
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
  1028
  by default (simp add: fun_eq_iff mult_ac)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1029
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1030
lemma fold_graph_insert_swap:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1031
assumes fold: "fold_graph times (b::'a) A y" and "b \<notin> A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1032
shows "fold_graph times z (insert b A) (z * y)"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1033
proof -
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
  1034
  interpret comp_fun_commute "op *::'a \<Rightarrow> 'a \<Rightarrow> 'a" by (rule comp_fun_commute)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1035
from assms show ?thesis
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1036
proof (induct rule: fold_graph.induct)
36045
b846881928ea simplify fold_graph proofs
huffman
parents: 35831
diff changeset
  1037
  case emptyI show ?case by (subst mult_commute [of z b], fast)
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1038
next
22262
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
  1039
  case (insertI x A y)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1040
    have "fold_graph times z (insert x (insert b A)) (x * (z * y))"
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1041
      using insertI by force  --{*how does @{term id} get unfolded?*}
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1042
    thus ?case by (simp add: insert_commute mult_ac)
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1043
qed
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1044
qed
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1045
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1046
lemma fold_graph_permute_diff:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1047
assumes fold: "fold_graph times b A x"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1048
shows "!!a. \<lbrakk>a \<in> A; b \<notin> A\<rbrakk> \<Longrightarrow> fold_graph times a (insert b (A-{a})) x"
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1049
using fold
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1050
proof (induct rule: fold_graph.induct)
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1051
  case emptyI thus ?case by simp
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1052
next
22262
96ba62dff413 Adapted to new inductive definition package.
berghofe
parents: 21733
diff changeset
  1053
  case (insertI x A y)
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1054
  have "a = x \<or> a \<in> A" using insertI by simp
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1055
  thus ?case
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1056
  proof
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1057
    assume "a = x"
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1058
    with insertI show ?thesis
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1059
      by (simp add: id_def [symmetric], blast intro: fold_graph_insert_swap)
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1060
  next
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1061
    assume ainA: "a \<in> A"
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1062
    hence "fold_graph times a (insert x (insert b (A - {a}))) (x * y)"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1063
      using insertI by force
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1064
    moreover
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1065
    have "insert x (insert b (A - {a})) = insert b (insert x A - {a})"
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1066
      using ainA insertI by blast
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1067
    ultimately show ?thesis by simp
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1068
  qed
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1069
qed
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1070
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1071
lemma fold1_eq_fold:
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1072
assumes "finite A" "a \<notin> A" shows "fold1 times (insert a A) = fold times a A"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1073
proof -
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
  1074
  interpret comp_fun_commute "op *::'a \<Rightarrow> 'a \<Rightarrow> 'a" by (rule comp_fun_commute)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1075
  from assms show ?thesis
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1076
apply (simp add: fold1_def fold_def)
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1077
apply (rule the_equality)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1078
apply (best intro: fold_graph_determ theI dest: finite_imp_fold_graph [of _ times])
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1079
apply (rule sym, clarify)
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1080
apply (case_tac "Aa=A")
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
  1081
 apply (best intro: fold_graph_determ)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1082
apply (subgoal_tac "fold_graph times a A x")
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
  1083
 apply (best intro: fold_graph_determ)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1084
apply (subgoal_tac "insert aa (Aa - {a}) = A")
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1085
 prefer 2 apply (blast elim: equalityE)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1086
apply (auto dest: fold_graph_permute_diff [where a=a])
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1087
done
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1088
qed
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1089
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1090
lemma nonempty_iff: "(A \<noteq> {}) = (\<exists>x B. A = insert x B & x \<notin> B)"
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1091
apply safe
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1092
 apply simp
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1093
 apply (drule_tac x=x in spec)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1094
 apply (drule_tac x="A-{x}" in spec, auto)
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1095
done
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1096
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1097
lemma fold1_insert:
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1098
  assumes nonempty: "A \<noteq> {}" and A: "finite A" "x \<notin> A"
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1099
  shows "fold1 times (insert x A) = x * fold1 times A"
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1100
proof -
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
  1101
  interpret comp_fun_commute "op *::'a \<Rightarrow> 'a \<Rightarrow> 'a" by (rule comp_fun_commute)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1102
  from nonempty obtain a A' where "A = insert a A' & a ~: A'"
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1103
    by (auto simp add: nonempty_iff)
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1104
  with A show ?thesis
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1105
    by (simp add: insert_commute [of x] fold1_eq_fold eq_commute)
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1106
qed
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1107
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1108
end
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1109
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1110
context ab_semigroup_idem_mult
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1111
begin
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1112
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
  1113
lemma comp_fun_idem: "comp_fun_idem (op *)"
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
  1114
  by default (simp_all add: fun_eq_iff mult_left_commute)
35817
d8b8527102f5 added locales folding_one_(idem); various streamlining and tuning
haftmann
parents: 35796
diff changeset
  1115
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1116
lemma fold1_insert_idem [simp]:
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1117
  assumes nonempty: "A \<noteq> {}" and A: "finite A" 
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1118
  shows "fold1 times (insert x A) = x * fold1 times A"
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1119
proof -
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
  1120
  interpret comp_fun_idem "op *::'a \<Rightarrow> 'a \<Rightarrow> 'a"
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
  1121
    by (rule comp_fun_idem)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1122
  from nonempty obtain a A' where A': "A = insert a A' & a ~: A'"
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1123
    by (auto simp add: nonempty_iff)
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1124
  show ?thesis
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1125
  proof cases
41550
efa734d9b221 eliminated global prems;
wenzelm
parents: 40945
diff changeset
  1126
    assume a: "a = x"
efa734d9b221 eliminated global prems;
wenzelm
parents: 40945
diff changeset
  1127
    show ?thesis
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1128
    proof cases
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1129
      assume "A' = {}"
41550
efa734d9b221 eliminated global prems;
wenzelm
parents: 40945
diff changeset
  1130
      with A' a show ?thesis by simp
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1131
    next
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1132
      assume "A' \<noteq> {}"
41550
efa734d9b221 eliminated global prems;
wenzelm
parents: 40945
diff changeset
  1133
      with A A' a show ?thesis
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
  1134
        by (simp add: fold1_insert mult_assoc [symmetric])
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1135
    qed
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1136
  next
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1137
    assume "a \<noteq> x"
41550
efa734d9b221 eliminated global prems;
wenzelm
parents: 40945
diff changeset
  1138
    with A A' show ?thesis
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
  1139
      by (simp add: insert_commute fold1_eq_fold)
15521
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1140
  qed
1ffd04343ac9 non-inductive fold1Set proofs
paulson
parents: 15520
diff changeset
  1141
qed
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1142
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1143
lemma hom_fold1_commute:
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1144
assumes hom: "!!x y. h (x * y) = h x * h y"
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1145
and N: "finite N" "N \<noteq> {}" shows "h (fold1 times N) = fold1 times (h ` N)"
46898
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
  1146
using N
1570b30ee040 tuned proofs -- eliminated pointless chaining of facts after 'interpret';
wenzelm
parents: 46146
diff changeset
  1147
proof (induct rule: finite_ne_induct)
22917
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1148
  case singleton thus ?case by simp
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1149
next
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1150
  case (insert n N)
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1151
  then have "h (fold1 times (insert n N)) = h (n * fold1 times N)" by simp
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1152
  also have "\<dots> = h n * h (fold1 times N)" by(rule hom)
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1153
  also have "h (fold1 times N) = fold1 times (h ` N)" by(rule insert)
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1154
  also have "times (h n) \<dots> = fold1 times (insert (h n) (h ` N))"
22917
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1155
    using insert by(simp)
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1156
  also have "insert (h n) (h ` N) = h ` insert n N" by simp
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1157
  finally show ?case .
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1158
qed
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1159
32679
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1160
lemma fold1_eq_fold_idem:
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1161
  assumes "finite A"
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1162
  shows "fold1 times (insert a A) = fold times a A"
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1163
proof (cases "a \<in> A")
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1164
  case False
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1165
  with assms show ?thesis by (simp add: fold1_eq_fold)
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1166
next
42871
1c0b99f950d9 names of fold_set locales resemble name of characteristic property more closely
haftmann
parents: 42869
diff changeset
  1167
  interpret comp_fun_idem times by (fact comp_fun_idem)
32679
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1168
  case True then obtain b B
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1169
    where A: "A = insert a B" and "a \<notin> B" by (rule set_insert)
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1170
  with assms have "finite B" by auto
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1171
  then have "fold times a (insert a B) = fold times (a * a) B"
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1172
    using `a \<notin> B` by (rule fold_insert2)
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1173
  then show ?thesis
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1174
    using `a \<notin> B` `finite B` by (simp add: fold1_eq_fold A)
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1175
qed
096306d7391d idempotency case for fold1
haftmann
parents: 32642
diff changeset
  1176
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1177
end
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1178
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1179
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1180
text{* Now the recursion rules for definitions: *}
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1181
22917
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1182
lemma fold1_singleton_def: "g = fold1 f \<Longrightarrow> g {a} = a"
35216
7641e8d831d2 get rid of many duplicate simp rule warnings
huffman
parents: 35171
diff changeset
  1183
by simp
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1184
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1185
lemma (in ab_semigroup_mult) fold1_insert_def:
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1186
  "\<lbrakk> g = fold1 times; finite A; x \<notin> A; A \<noteq> {} \<rbrakk> \<Longrightarrow> g (insert x A) = x * g A"
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1187
by (simp add:fold1_insert)
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1188
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1189
lemma (in ab_semigroup_idem_mult) fold1_insert_idem_def:
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1190
  "\<lbrakk> g = fold1 times; finite A; A \<noteq> {} \<rbrakk> \<Longrightarrow> g (insert x A) = x * g A"
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1191
by simp
15508
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1192
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1193
subsubsection{* Determinacy for @{term fold1Set} *}
c09defa4c956 revised fold1 proofs
paulson
parents: 15507
diff changeset
  1194
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1195
(*Not actually used!!*)
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1196
(*
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1197
context ab_semigroup_mult
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1198
begin
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1199
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1200
lemma fold_graph_permute:
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1201
  "[|fold_graph times id b (insert a A) x; a \<notin> A; b \<notin> A|]
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1202
   ==> fold_graph times id a (insert b A) x"
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1203
apply (cases "a=b") 
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1204
apply (auto dest: fold_graph_permute_diff) 
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1205
done
15376
302ef111b621 Started to clean up and generalize FiniteSet
nipkow
parents: 15327
diff changeset
  1206
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1207
lemma fold1Set_determ:
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1208
  "fold1Set times A x ==> fold1Set times A y ==> y = x"
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1209
proof (clarify elim!: fold1Set.cases)
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1210
  fix A x B y a b
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1211
  assume Ax: "fold_graph times id a A x"
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1212
  assume By: "fold_graph times id b B y"
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1213
  assume anotA:  "a \<notin> A"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1214
  assume bnotB:  "b \<notin> B"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1215
  assume eq: "insert a A = insert b B"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1216
  show "y=x"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1217
  proof cases
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1218
    assume same: "a=b"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1219
    hence "A=B" using anotA bnotB eq by (blast elim!: equalityE)
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1220
    thus ?thesis using Ax By same by (blast intro: fold_graph_determ)
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
  1221
  next
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1222
    assume diff: "a\<noteq>b"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1223
    let ?D = "B - {a}"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1224
    have B: "B = insert a ?D" and A: "A = insert b ?D"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1225
     and aB: "a \<in> B" and bA: "b \<in> A"
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1226
      using eq anotA bnotB diff by (blast elim!:equalityE)+
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1227
    with aB bnotB By
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1228
    have "fold_graph times id a (insert b ?D) y" 
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1229
      by (auto intro: fold_graph_permute simp add: insert_absorb)
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1230
    moreover
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1231
    have "fold_graph times id a (insert b ?D) x"
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1232
      by (simp add: A [symmetric] Ax) 
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1233
    ultimately show ?thesis by (blast intro: fold_graph_determ) 
15392
290bc97038c7 First step in reorganizing Finite_Set
nipkow
parents: 15376
diff changeset
  1234
  qed
12396
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
  1235
qed
2298d5b8e530 renamed theory Finite to Finite_Set and converted;
wenzelm
parents:
diff changeset
  1236
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1237
lemma fold1Set_equality: "fold1Set times A y ==> fold1 times A = y"
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1238
  by (unfold fold1_def) (blast intro: fold1Set_determ)
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1239
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1240
end
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1241
*)
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1242
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1243
declare
28853
69eb69659bf3 Added new fold operator and renamed the old oe to fold_image.
nipkow
parents: 28823
diff changeset
  1244
  empty_fold_graphE [rule del]  fold_graph.intros [rule del]
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1245
  empty_fold1SetE [rule del]  insert_fold1SetE [rule del]
19931
fb32b43e7f80 Restructured locales with predicates: import is now an interpretation.
ballarin
parents: 19870
diff changeset
  1246
  -- {* No more proofs involve these relations. *}
15376
302ef111b621 Started to clean up and generalize FiniteSet
nipkow
parents: 15327
diff changeset
  1247
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1248
subsubsection {* Lemmas about @{text fold1} *}
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1249
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1250
context ab_semigroup_mult
22917
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1251
begin
3c56b12fd946 localized Min/Max
haftmann
parents: 22616
diff changeset
  1252
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1253
lemma fold1_Un:
15484
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1254
assumes A: "finite A" "A \<noteq> {}"
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1255
shows "finite B \<Longrightarrow> B \<noteq> {} \<Longrightarrow> A Int B = {} \<Longrightarrow>
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1256
       fold1 times (A Un B) = fold1 times A * fold1 times B"
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1257
using A by (induct rule: finite_ne_induct)
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1258
  (simp_all add: fold1_insert mult_assoc)
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1259
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1260
lemma fold1_in:
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1261
  assumes A: "finite (A)" "A \<noteq> {}" and elem: "\<And>x y. x * y \<in> {x,y}"
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1262
  shows "fold1 times A \<in> A"
15484
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1263
using A
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1264
proof (induct rule:finite_ne_induct)
15506
864238c95b56 new treatment of fold1
paulson
parents: 15505
diff changeset
  1265
  case singleton thus ?case by simp
15484
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1266
next
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1267
  case insert thus ?case using elem by (force simp add:fold1_insert)
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1268
qed
2636ec211ec8 fold and fol1 changes
nipkow
parents: 15483
diff changeset
  1269
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1270
end
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1271
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1272
lemma (in ab_semigroup_idem_mult) fold1_Un2:
15497
53bca254719a Added semi-lattice locales and reorganized fold1 lemmas
nipkow
parents: 15487
diff changeset
  1273
assumes A: "finite A" "A \<noteq> {}"
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1274
shows "finite B \<Longrightarrow> B \<noteq> {} \<Longrightarrow>
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1275
       fold1 times (A Un B) = fold1 times A * fold1 times B"
15497
53bca254719a Added semi-lattice locales and reorganized fold1 lemmas
nipkow
parents: 15487
diff changeset
  1276
using A
26041
c2e15e65165f locales ACf, ACIf, ACIfSL and ACIfSLlin have been abandoned in favour of the existing algebraic classes ab_semigroup_mult, ab_semigroup_idem_mult, lower_semilattice (resp. uper_semilattice) and linorder
haftmann
parents: 25571
diff changeset
  1277
proof(induct rule:finite_ne_induct)
15497
53bca254719a Added semi-lattice locales and reorganized fold1 lemmas
nipkow
parents: 15487
diff changeset
  1278
  case singleton thus ?case by simp