nipkow@8924
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(* Title: HOL/SetInterval.thy
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ballarin@13735
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Author: Tobias Nipkow and Clemens Ballarin
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paulson@14485
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Additions by Jeremy Avigad in March 2004
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paulson@8957
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Copyright 2000 TU Muenchen
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ballarin@13735
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lessThan, greaterThan, atLeast, atMost and two-sided intervals
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*)
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nipkow@8924
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wenzelm@14577
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header {* Set intervals *}
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nipkow@15131
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theory SetInterval
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haftmann@25919
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imports Int
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begin
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context ord
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begin
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definition
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haftmann@25062
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lessThan :: "'a => 'a set" ("(1{..<_})") where
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"{..<u} == {x. x < u}"
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definition
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atMost :: "'a => 'a set" ("(1{.._})") where
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"{..u} == {x. x \<le> u}"
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definition
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greaterThan :: "'a => 'a set" ("(1{_<..})") where
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"{l<..} == {x. l<x}"
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definition
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atLeast :: "'a => 'a set" ("(1{_..})") where
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"{l..} == {x. l\<le>x}"
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definition
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haftmann@25062
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greaterThanLessThan :: "'a => 'a => 'a set" ("(1{_<..<_})") where
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haftmann@25062
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"{l<..<u} == {l<..} Int {..<u}"
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nipkow@24691
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definition
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haftmann@25062
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atLeastLessThan :: "'a => 'a => 'a set" ("(1{_..<_})") where
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haftmann@25062
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"{l..<u} == {l..} Int {..<u}"
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definition
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haftmann@25062
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greaterThanAtMost :: "'a => 'a => 'a set" ("(1{_<.._})") where
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haftmann@25062
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"{l<..u} == {l<..} Int {..u}"
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definition
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haftmann@25062
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atLeastAtMost :: "'a => 'a => 'a set" ("(1{_.._})") where
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haftmann@25062
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"{l..u} == {l..} Int {..u}"
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nipkow@24691
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end
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ballarin@13735
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text{* A note of warning when using @{term"{..<n}"} on type @{typ
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nat}: it is equivalent to @{term"{0::nat..<n}"} but some lemmas involving
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@{term"{m..<n}"} may not exist in @{term"{..<n}"}-form as well. *}
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syntax
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"@UNION_le" :: "nat => nat => 'b set => 'b set" ("(3UN _<=_./ _)" 10)
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"@UNION_less" :: "nat => nat => 'b set => 'b set" ("(3UN _<_./ _)" 10)
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"@INTER_le" :: "nat => nat => 'b set => 'b set" ("(3INT _<=_./ _)" 10)
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"@INTER_less" :: "nat => nat => 'b set => 'b set" ("(3INT _<_./ _)" 10)
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syntax (input)
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"@UNION_le" :: "nat => nat => 'b set => 'b set" ("(3\<Union> _\<le>_./ _)" 10)
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"@UNION_less" :: "nat => nat => 'b set => 'b set" ("(3\<Union> _<_./ _)" 10)
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kleing@14418
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"@INTER_le" :: "nat => nat => 'b set => 'b set" ("(3\<Inter> _\<le>_./ _)" 10)
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"@INTER_less" :: "nat => nat => 'b set => 'b set" ("(3\<Inter> _<_./ _)" 10)
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syntax (xsymbols)
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"@UNION_le" :: "nat \<Rightarrow> nat => 'b set => 'b set" ("(3\<Union>(00\<^bsub>_ \<le> _\<^esub>)/ _)" 10)
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"@UNION_less" :: "nat \<Rightarrow> nat => 'b set => 'b set" ("(3\<Union>(00\<^bsub>_ < _\<^esub>)/ _)" 10)
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"@INTER_le" :: "nat \<Rightarrow> nat => 'b set => 'b set" ("(3\<Inter>(00\<^bsub>_ \<le> _\<^esub>)/ _)" 10)
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wenzelm@14846
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"@INTER_less" :: "nat \<Rightarrow> nat => 'b set => 'b set" ("(3\<Inter>(00\<^bsub>_ < _\<^esub>)/ _)" 10)
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kleing@14418
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kleing@14418
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translations
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"UN i<=n. A" == "UN i:{..n}. A"
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"UN i<n. A" == "UN i:{..<n}. A"
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kleing@14418
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"INT i<=n. A" == "INT i:{..n}. A"
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"INT i<n. A" == "INT i:{..<n}. A"
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kleing@14418
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paulson@14485
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subsection {* Various equivalences *}
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lemma (in ord) lessThan_iff [iff]: "(i: lessThan k) = (i<k)"
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by (simp add: lessThan_def)
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lemma Compl_lessThan [simp]:
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"!!k:: 'a::linorder. -lessThan k = atLeast k"
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apply (auto simp add: lessThan_def atLeast_def)
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done
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lemma single_Diff_lessThan [simp]: "!!k:: 'a::order. {k} - lessThan k = {k}"
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by auto
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lemma (in ord) greaterThan_iff [iff]: "(i: greaterThan k) = (k<i)"
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by (simp add: greaterThan_def)
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lemma Compl_greaterThan [simp]:
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"!!k:: 'a::linorder. -greaterThan k = atMost k"
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haftmann@26072
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by (auto simp add: greaterThan_def atMost_def)
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ballarin@13735
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paulson@13850
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lemma Compl_atMost [simp]: "!!k:: 'a::linorder. -atMost k = greaterThan k"
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paulson@13850
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apply (subst Compl_greaterThan [symmetric])
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paulson@15418
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apply (rule double_complement)
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ballarin@13735
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done
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ballarin@13735
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haftmann@25062
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lemma (in ord) atLeast_iff [iff]: "(i: atLeast k) = (k<=i)"
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paulson@13850
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by (simp add: atLeast_def)
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paulson@13850
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paulson@15418
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lemma Compl_atLeast [simp]:
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paulson@13850
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"!!k:: 'a::linorder. -atLeast k = lessThan k"
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haftmann@26072
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by (auto simp add: lessThan_def atLeast_def)
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ballarin@13735
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haftmann@25062
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lemma (in ord) atMost_iff [iff]: "(i: atMost k) = (i<=k)"
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paulson@13850
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by (simp add: atMost_def)
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ballarin@13735
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paulson@14485
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lemma atMost_Int_atLeast: "!!n:: 'a::order. atMost n Int atLeast n = {n}"
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paulson@14485
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by (blast intro: order_antisym)
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ballarin@13735
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ballarin@13735
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paulson@14485
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subsection {* Logical Equivalences for Set Inclusion and Equality *}
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paulson@13850
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paulson@13850
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lemma atLeast_subset_iff [iff]:
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paulson@15418
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"(atLeast x \<subseteq> atLeast y) = (y \<le> (x::'a::order))"
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paulson@15418
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by (blast intro: order_trans)
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paulson@13850
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paulson@13850
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lemma atLeast_eq_iff [iff]:
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paulson@15418
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"(atLeast x = atLeast y) = (x = (y::'a::linorder))"
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paulson@13850
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by (blast intro: order_antisym order_trans)
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paulson@13850
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paulson@13850
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lemma greaterThan_subset_iff [iff]:
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paulson@15418
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"(greaterThan x \<subseteq> greaterThan y) = (y \<le> (x::'a::linorder))"
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paulson@15418
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apply (auto simp add: greaterThan_def)
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paulson@15418
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apply (subst linorder_not_less [symmetric], blast)
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ballarin@13735
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done
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ballarin@13735
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paulson@13850
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lemma greaterThan_eq_iff [iff]:
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paulson@15418
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"(greaterThan x = greaterThan y) = (x = (y::'a::linorder))"
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paulson@15418
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apply (rule iffI)
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apply (erule equalityE)
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haftmann@29709
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apply simp_all
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done
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paulson@15418
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lemma atMost_subset_iff [iff]: "(atMost x \<subseteq> atMost y) = (x \<le> (y::'a::order))"
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paulson@13850
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by (blast intro: order_trans)
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paulson@13850
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paulson@15418
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lemma atMost_eq_iff [iff]: "(atMost x = atMost y) = (x = (y::'a::linorder))"
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paulson@13850
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by (blast intro: order_antisym order_trans)
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paulson@13850
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paulson@13850
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lemma lessThan_subset_iff [iff]:
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paulson@15418
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"(lessThan x \<subseteq> lessThan y) = (x \<le> (y::'a::linorder))"
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paulson@15418
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apply (auto simp add: lessThan_def)
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paulson@15418
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apply (subst linorder_not_less [symmetric], blast)
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paulson@13850
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done
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paulson@13850
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paulson@13850
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lemma lessThan_eq_iff [iff]:
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paulson@15418
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"(lessThan x = lessThan y) = (x = (y::'a::linorder))"
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paulson@15418
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apply (rule iffI)
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paulson@15418
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apply (erule equalityE)
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haftmann@29709
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apply simp_all
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paulson@13850
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done
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paulson@13850
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paulson@13850
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paulson@13850
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subsection {*Two-sided intervals*}
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context ord
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begin
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nipkow@24691
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paulson@24286
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lemma greaterThanLessThan_iff [simp,noatp]:
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haftmann@25062
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"(i : {l<..<u}) = (l < i & i < u)"
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ballarin@13735
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by (simp add: greaterThanLessThan_def)
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ballarin@13735
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paulson@24286
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lemma atLeastLessThan_iff [simp,noatp]:
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haftmann@25062
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"(i : {l..<u}) = (l <= i & i < u)"
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ballarin@13735
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by (simp add: atLeastLessThan_def)
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ballarin@13735
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paulson@24286
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lemma greaterThanAtMost_iff [simp,noatp]:
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haftmann@25062
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"(i : {l<..u}) = (l < i & i <= u)"
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ballarin@13735
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by (simp add: greaterThanAtMost_def)
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ballarin@13735
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paulson@24286
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lemma atLeastAtMost_iff [simp,noatp]:
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haftmann@25062
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"(i : {l..u}) = (l <= i & i <= u)"
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ballarin@13735
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by (simp add: atLeastAtMost_def)
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ballarin@13735
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wenzelm@14577
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text {* The above four lemmas could be declared as iffs.
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wenzelm@14577
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If we do so, a call to blast in Hyperreal/Star.ML, lemma @{text STAR_Int}
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wenzelm@14577
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seems to take forever (more than one hour). *}
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nipkow@24691
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end
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ballarin@13735
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nipkow@15554
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subsubsection{* Emptyness and singletons *}
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nipkow@15554
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nipkow@24691
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context order
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begin
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nipkow@15554
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haftmann@25062
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lemma atLeastAtMost_empty [simp]: "n < m ==> {m..n} = {}";
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nipkow@24691
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by (auto simp add: atLeastAtMost_def atMost_def atLeast_def)
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nipkow@24691
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haftmann@25062
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lemma atLeastLessThan_empty[simp]: "n \<le> m ==> {m..<n} = {}"
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nipkow@15554
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by (auto simp add: atLeastLessThan_def)
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nipkow@15554
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haftmann@25062
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lemma greaterThanAtMost_empty[simp]:"l \<le> k ==> {k<..l} = {}"
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nipkow@17719
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by(auto simp:greaterThanAtMost_def greaterThan_def atMost_def)
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nipkow@17719
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haftmann@29709
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lemma greaterThanLessThan_empty[simp]:"l \<le> k ==> {k<..<l} = {}"
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nipkow@17719
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by(auto simp:greaterThanLessThan_def greaterThan_def lessThan_def)
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nipkow@17719
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haftmann@25062
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lemma atLeastAtMost_singleton [simp]: "{a..a} = {a}"
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nipkow@24691
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by (auto simp add: atLeastAtMost_def atMost_def atLeast_def)
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nipkow@24691
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nipkow@24691
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end
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paulson@14485
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paulson@14485
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subsection {* Intervals of natural numbers *}
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paulson@14485
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paulson@15047
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subsubsection {* The Constant @{term lessThan} *}
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paulson@15047
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paulson@14485
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lemma lessThan_0 [simp]: "lessThan (0::nat) = {}"
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paulson@14485
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by (simp add: lessThan_def)
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paulson@14485
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paulson@14485
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lemma lessThan_Suc: "lessThan (Suc k) = insert k (lessThan k)"
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paulson@14485
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by (simp add: lessThan_def less_Suc_eq, blast)
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paulson@14485
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paulson@14485
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lemma lessThan_Suc_atMost: "lessThan (Suc k) = atMost k"
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paulson@14485
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by (simp add: lessThan_def atMost_def less_Suc_eq_le)
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paulson@14485
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paulson@14485
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lemma UN_lessThan_UNIV: "(UN m::nat. lessThan m) = UNIV"
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paulson@14485
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by blast
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paulson@14485
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paulson@15047
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subsubsection {* The Constant @{term greaterThan} *}
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paulson@15047
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paulson@14485
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lemma greaterThan_0 [simp]: "greaterThan 0 = range Suc"
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paulson@14485
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apply (simp add: greaterThan_def)
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paulson@14485
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apply (blast dest: gr0_conv_Suc [THEN iffD1])
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paulson@14485
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done
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paulson@14485
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paulson@14485
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lemma greaterThan_Suc: "greaterThan (Suc k) = greaterThan k - {Suc k}"
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paulson@14485
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apply (simp add: greaterThan_def)
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paulson@14485
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apply (auto elim: linorder_neqE)
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paulson@14485
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done
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paulson@14485
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paulson@14485
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lemma INT_greaterThan_UNIV: "(INT m::nat. greaterThan m) = {}"
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paulson@14485
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by blast
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paulson@14485
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paulson@15047
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subsubsection {* The Constant @{term atLeast} *}
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paulson@15047
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paulson@14485
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lemma atLeast_0 [simp]: "atLeast (0::nat) = UNIV"
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paulson@14485
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by (unfold atLeast_def UNIV_def, simp)
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paulson@14485
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paulson@14485
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lemma atLeast_Suc: "atLeast (Suc k) = atLeast k - {k}"
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paulson@14485
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apply (simp add: atLeast_def)
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paulson@14485
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apply (simp add: Suc_le_eq)
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paulson@14485
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apply (simp add: order_le_less, blast)
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paulson@14485
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done
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paulson@14485
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paulson@14485
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lemma atLeast_Suc_greaterThan: "atLeast (Suc k) = greaterThan k"
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paulson@14485
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by (auto simp add: greaterThan_def atLeast_def less_Suc_eq_le)
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paulson@14485
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paulson@14485
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lemma UN_atLeast_UNIV: "(UN m::nat. atLeast m) = UNIV"
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paulson@14485
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by blast
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paulson@14485
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paulson@15047
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subsubsection {* The Constant @{term atMost} *}
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paulson@15047
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paulson@14485
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lemma atMost_0 [simp]: "atMost (0::nat) = {0}"
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paulson@14485
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by (simp add: atMost_def)
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paulson@14485
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paulson@14485
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lemma atMost_Suc: "atMost (Suc k) = insert (Suc k) (atMost k)"
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paulson@14485
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apply (simp add: atMost_def)
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paulson@14485
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apply (simp add: less_Suc_eq order_le_less, blast)
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paulson@14485
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done
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paulson@14485
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paulson@14485
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lemma UN_atMost_UNIV: "(UN m::nat. atMost m) = UNIV"
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paulson@14485
|
270 |
by blast
|
paulson@14485
|
271 |
|
paulson@15047
|
272 |
subsubsection {* The Constant @{term atLeastLessThan} *}
|
paulson@15047
|
273 |
|
nipkow@28068
|
274 |
text{*The orientation of the following 2 rules is tricky. The lhs is
|
nipkow@24449
|
275 |
defined in terms of the rhs. Hence the chosen orientation makes sense
|
nipkow@24449
|
276 |
in this theory --- the reverse orientation complicates proofs (eg
|
nipkow@24449
|
277 |
nontermination). But outside, when the definition of the lhs is rarely
|
nipkow@24449
|
278 |
used, the opposite orientation seems preferable because it reduces a
|
nipkow@24449
|
279 |
specific concept to a more general one. *}
|
nipkow@28068
|
280 |
|
paulson@15047
|
281 |
lemma atLeast0LessThan: "{0::nat..<n} = {..<n}"
|
nipkow@15042
|
282 |
by(simp add:lessThan_def atLeastLessThan_def)
|
nipkow@24449
|
283 |
|
nipkow@28068
|
284 |
lemma atLeast0AtMost: "{0..n::nat} = {..n}"
|
nipkow@28068
|
285 |
by(simp add:atMost_def atLeastAtMost_def)
|
nipkow@28068
|
286 |
|
nipkow@24449
|
287 |
declare atLeast0LessThan[symmetric, code unfold]
|
nipkow@28068
|
288 |
atLeast0AtMost[symmetric, code unfold]
|
nipkow@24449
|
289 |
|
nipkow@24449
|
290 |
lemma atLeastLessThan0: "{m..<0::nat} = {}"
|
paulson@15047
|
291 |
by (simp add: atLeastLessThan_def)
|
nipkow@24449
|
292 |
|
paulson@15047
|
293 |
subsubsection {* Intervals of nats with @{term Suc} *}
|
paulson@15047
|
294 |
|
paulson@15047
|
295 |
text{*Not a simprule because the RHS is too messy.*}
|
paulson@15047
|
296 |
lemma atLeastLessThanSuc:
|
paulson@15047
|
297 |
"{m..<Suc n} = (if m \<le> n then insert n {m..<n} else {})"
|
paulson@15418
|
298 |
by (auto simp add: atLeastLessThan_def)
|
paulson@15047
|
299 |
|
paulson@15418
|
300 |
lemma atLeastLessThan_singleton [simp]: "{m..<Suc m} = {m}"
|
paulson@15047
|
301 |
by (auto simp add: atLeastLessThan_def)
|
nipkow@16041
|
302 |
(*
|
paulson@15047
|
303 |
lemma atLeast_sum_LessThan [simp]: "{m + k..<k::nat} = {}"
|
paulson@15047
|
304 |
by (induct k, simp_all add: atLeastLessThanSuc)
|
paulson@15047
|
305 |
|
paulson@15047
|
306 |
lemma atLeastSucLessThan [simp]: "{Suc n..<n} = {}"
|
paulson@15047
|
307 |
by (auto simp add: atLeastLessThan_def)
|
nipkow@16041
|
308 |
*)
|
nipkow@15045
|
309 |
lemma atLeastLessThanSuc_atLeastAtMost: "{l..<Suc u} = {l..u}"
|
paulson@14485
|
310 |
by (simp add: lessThan_Suc_atMost atLeastAtMost_def atLeastLessThan_def)
|
paulson@14485
|
311 |
|
paulson@15418
|
312 |
lemma atLeastSucAtMost_greaterThanAtMost: "{Suc l..u} = {l<..u}"
|
paulson@15418
|
313 |
by (simp add: atLeast_Suc_greaterThan atLeastAtMost_def
|
paulson@14485
|
314 |
greaterThanAtMost_def)
|
paulson@14485
|
315 |
|
paulson@15418
|
316 |
lemma atLeastSucLessThan_greaterThanLessThan: "{Suc l..<u} = {l<..<u}"
|
paulson@15418
|
317 |
by (simp add: atLeast_Suc_greaterThan atLeastLessThan_def
|
paulson@14485
|
318 |
greaterThanLessThan_def)
|
paulson@14485
|
319 |
|
nipkow@15554
|
320 |
lemma atLeastAtMostSuc_conv: "m \<le> Suc n \<Longrightarrow> {m..Suc n} = insert (Suc n) {m..n}"
|
nipkow@15554
|
321 |
by (auto simp add: atLeastAtMost_def)
|
nipkow@15554
|
322 |
|
nipkow@16733
|
323 |
subsubsection {* Image *}
|
nipkow@16733
|
324 |
|
nipkow@16733
|
325 |
lemma image_add_atLeastAtMost:
|
nipkow@16733
|
326 |
"(%n::nat. n+k) ` {i..j} = {i+k..j+k}" (is "?A = ?B")
|
nipkow@16733
|
327 |
proof
|
nipkow@16733
|
328 |
show "?A \<subseteq> ?B" by auto
|
nipkow@16733
|
329 |
next
|
nipkow@16733
|
330 |
show "?B \<subseteq> ?A"
|
nipkow@16733
|
331 |
proof
|
nipkow@16733
|
332 |
fix n assume a: "n : ?B"
|
webertj@20217
|
333 |
hence "n - k : {i..j}" by auto
|
nipkow@16733
|
334 |
moreover have "n = (n - k) + k" using a by auto
|
nipkow@16733
|
335 |
ultimately show "n : ?A" by blast
|
nipkow@16733
|
336 |
qed
|
nipkow@16733
|
337 |
qed
|
nipkow@16733
|
338 |
|
nipkow@16733
|
339 |
lemma image_add_atLeastLessThan:
|
nipkow@16733
|
340 |
"(%n::nat. n+k) ` {i..<j} = {i+k..<j+k}" (is "?A = ?B")
|
nipkow@16733
|
341 |
proof
|
nipkow@16733
|
342 |
show "?A \<subseteq> ?B" by auto
|
nipkow@16733
|
343 |
next
|
nipkow@16733
|
344 |
show "?B \<subseteq> ?A"
|
nipkow@16733
|
345 |
proof
|
nipkow@16733
|
346 |
fix n assume a: "n : ?B"
|
webertj@20217
|
347 |
hence "n - k : {i..<j}" by auto
|
nipkow@16733
|
348 |
moreover have "n = (n - k) + k" using a by auto
|
nipkow@16733
|
349 |
ultimately show "n : ?A" by blast
|
nipkow@16733
|
350 |
qed
|
nipkow@16733
|
351 |
qed
|
nipkow@16733
|
352 |
|
nipkow@16733
|
353 |
corollary image_Suc_atLeastAtMost[simp]:
|
nipkow@16733
|
354 |
"Suc ` {i..j} = {Suc i..Suc j}"
|
nipkow@16733
|
355 |
using image_add_atLeastAtMost[where k=1] by simp
|
nipkow@16733
|
356 |
|
nipkow@16733
|
357 |
corollary image_Suc_atLeastLessThan[simp]:
|
nipkow@16733
|
358 |
"Suc ` {i..<j} = {Suc i..<Suc j}"
|
nipkow@16733
|
359 |
using image_add_atLeastLessThan[where k=1] by simp
|
nipkow@16733
|
360 |
|
nipkow@16733
|
361 |
lemma image_add_int_atLeastLessThan:
|
nipkow@16733
|
362 |
"(%x. x + (l::int)) ` {0..<u-l} = {l..<u}"
|
nipkow@16733
|
363 |
apply (auto simp add: image_def)
|
nipkow@16733
|
364 |
apply (rule_tac x = "x - l" in bexI)
|
nipkow@16733
|
365 |
apply auto
|
nipkow@16733
|
366 |
done
|
nipkow@16733
|
367 |
|
nipkow@16733
|
368 |
|
paulson@14485
|
369 |
subsubsection {* Finiteness *}
|
paulson@14485
|
370 |
|
nipkow@15045
|
371 |
lemma finite_lessThan [iff]: fixes k :: nat shows "finite {..<k}"
|
paulson@14485
|
372 |
by (induct k) (simp_all add: lessThan_Suc)
|
paulson@14485
|
373 |
|
paulson@14485
|
374 |
lemma finite_atMost [iff]: fixes k :: nat shows "finite {..k}"
|
paulson@14485
|
375 |
by (induct k) (simp_all add: atMost_Suc)
|
paulson@14485
|
376 |
|
paulson@14485
|
377 |
lemma finite_greaterThanLessThan [iff]:
|
nipkow@15045
|
378 |
fixes l :: nat shows "finite {l<..<u}"
|
paulson@14485
|
379 |
by (simp add: greaterThanLessThan_def)
|
paulson@14485
|
380 |
|
paulson@14485
|
381 |
lemma finite_atLeastLessThan [iff]:
|
nipkow@15045
|
382 |
fixes l :: nat shows "finite {l..<u}"
|
paulson@14485
|
383 |
by (simp add: atLeastLessThan_def)
|
paulson@14485
|
384 |
|
paulson@14485
|
385 |
lemma finite_greaterThanAtMost [iff]:
|
nipkow@15045
|
386 |
fixes l :: nat shows "finite {l<..u}"
|
paulson@14485
|
387 |
by (simp add: greaterThanAtMost_def)
|
paulson@14485
|
388 |
|
paulson@14485
|
389 |
lemma finite_atLeastAtMost [iff]:
|
paulson@14485
|
390 |
fixes l :: nat shows "finite {l..u}"
|
paulson@14485
|
391 |
by (simp add: atLeastAtMost_def)
|
paulson@14485
|
392 |
|
nipkow@28068
|
393 |
text {* A bounded set of natural numbers is finite. *}
|
paulson@14485
|
394 |
lemma bounded_nat_set_is_finite:
|
nipkow@24853
|
395 |
"(ALL i:N. i < (n::nat)) ==> finite N"
|
nipkow@28068
|
396 |
apply (rule finite_subset)
|
nipkow@28068
|
397 |
apply (rule_tac [2] finite_lessThan, auto)
|
nipkow@28068
|
398 |
done
|
nipkow@28068
|
399 |
|
nipkow@28068
|
400 |
lemma finite_less_ub:
|
nipkow@28068
|
401 |
"!!f::nat=>nat. (!!n. n \<le> f n) ==> finite {n. f n \<le> u}"
|
nipkow@28068
|
402 |
by (rule_tac B="{..u}" in finite_subset, auto intro: order_trans)
|
paulson@14485
|
403 |
|
nipkow@24853
|
404 |
text{* Any subset of an interval of natural numbers the size of the
|
nipkow@24853
|
405 |
subset is exactly that interval. *}
|
nipkow@24853
|
406 |
|
nipkow@24853
|
407 |
lemma subset_card_intvl_is_intvl:
|
nipkow@24853
|
408 |
"A <= {k..<k+card A} \<Longrightarrow> A = {k..<k+card A}" (is "PROP ?P")
|
nipkow@24853
|
409 |
proof cases
|
nipkow@24853
|
410 |
assume "finite A"
|
nipkow@24853
|
411 |
thus "PROP ?P"
|
nipkow@24853
|
412 |
proof(induct A rule:finite_linorder_induct)
|
nipkow@24853
|
413 |
case empty thus ?case by auto
|
nipkow@24853
|
414 |
next
|
nipkow@24853
|
415 |
case (insert A b)
|
nipkow@24853
|
416 |
moreover hence "b ~: A" by auto
|
nipkow@24853
|
417 |
moreover have "A <= {k..<k+card A}" and "b = k+card A"
|
nipkow@24853
|
418 |
using `b ~: A` insert by fastsimp+
|
nipkow@24853
|
419 |
ultimately show ?case by auto
|
nipkow@24853
|
420 |
qed
|
nipkow@24853
|
421 |
next
|
nipkow@24853
|
422 |
assume "~finite A" thus "PROP ?P" by simp
|
nipkow@24853
|
423 |
qed
|
nipkow@24853
|
424 |
|
nipkow@24853
|
425 |
|
paulson@14485
|
426 |
subsubsection {* Cardinality *}
|
paulson@14485
|
427 |
|
nipkow@15045
|
428 |
lemma card_lessThan [simp]: "card {..<u} = u"
|
paulson@15251
|
429 |
by (induct u, simp_all add: lessThan_Suc)
|
paulson@14485
|
430 |
|
paulson@14485
|
431 |
lemma card_atMost [simp]: "card {..u} = Suc u"
|
paulson@14485
|
432 |
by (simp add: lessThan_Suc_atMost [THEN sym])
|
paulson@14485
|
433 |
|
nipkow@15045
|
434 |
lemma card_atLeastLessThan [simp]: "card {l..<u} = u - l"
|
nipkow@15045
|
435 |
apply (subgoal_tac "card {l..<u} = card {..<u-l}")
|
paulson@14485
|
436 |
apply (erule ssubst, rule card_lessThan)
|
nipkow@15045
|
437 |
apply (subgoal_tac "(%x. x + l) ` {..<u-l} = {l..<u}")
|
paulson@14485
|
438 |
apply (erule subst)
|
paulson@14485
|
439 |
apply (rule card_image)
|
paulson@14485
|
440 |
apply (simp add: inj_on_def)
|
paulson@14485
|
441 |
apply (auto simp add: image_def atLeastLessThan_def lessThan_def)
|
paulson@14485
|
442 |
apply (rule_tac x = "x - l" in exI)
|
paulson@14485
|
443 |
apply arith
|
paulson@14485
|
444 |
done
|
paulson@14485
|
445 |
|
paulson@15418
|
446 |
lemma card_atLeastAtMost [simp]: "card {l..u} = Suc u - l"
|
paulson@14485
|
447 |
by (subst atLeastLessThanSuc_atLeastAtMost [THEN sym], simp)
|
paulson@14485
|
448 |
|
paulson@15418
|
449 |
lemma card_greaterThanAtMost [simp]: "card {l<..u} = u - l"
|
paulson@14485
|
450 |
by (subst atLeastSucAtMost_greaterThanAtMost [THEN sym], simp)
|
paulson@14485
|
451 |
|
nipkow@15045
|
452 |
lemma card_greaterThanLessThan [simp]: "card {l<..<u} = u - Suc l"
|
paulson@14485
|
453 |
by (subst atLeastSucLessThan_greaterThanLessThan [THEN sym], simp)
|
paulson@14485
|
454 |
|
nipkow@26105
|
455 |
|
nipkow@26105
|
456 |
lemma ex_bij_betw_nat_finite:
|
nipkow@26105
|
457 |
"finite M \<Longrightarrow> \<exists>h. bij_betw h {0..<card M} M"
|
nipkow@26105
|
458 |
apply(drule finite_imp_nat_seg_image_inj_on)
|
nipkow@26105
|
459 |
apply(auto simp:atLeast0LessThan[symmetric] lessThan_def[symmetric] card_image bij_betw_def)
|
nipkow@26105
|
460 |
done
|
nipkow@26105
|
461 |
|
nipkow@26105
|
462 |
lemma ex_bij_betw_finite_nat:
|
nipkow@26105
|
463 |
"finite M \<Longrightarrow> \<exists>h. bij_betw h M {0..<card M}"
|
nipkow@26105
|
464 |
by (blast dest: ex_bij_betw_nat_finite bij_betw_inv)
|
nipkow@26105
|
465 |
|
nipkow@26105
|
466 |
|
paulson@14485
|
467 |
subsection {* Intervals of integers *}
|
paulson@14485
|
468 |
|
nipkow@15045
|
469 |
lemma atLeastLessThanPlusOne_atLeastAtMost_int: "{l..<u+1} = {l..(u::int)}"
|
paulson@14485
|
470 |
by (auto simp add: atLeastAtMost_def atLeastLessThan_def)
|
paulson@14485
|
471 |
|
paulson@15418
|
472 |
lemma atLeastPlusOneAtMost_greaterThanAtMost_int: "{l+1..u} = {l<..(u::int)}"
|
paulson@14485
|
473 |
by (auto simp add: atLeastAtMost_def greaterThanAtMost_def)
|
paulson@14485
|
474 |
|
paulson@15418
|
475 |
lemma atLeastPlusOneLessThan_greaterThanLessThan_int:
|
paulson@15418
|
476 |
"{l+1..<u} = {l<..<u::int}"
|
paulson@14485
|
477 |
by (auto simp add: atLeastLessThan_def greaterThanLessThan_def)
|
paulson@14485
|
478 |
|
paulson@14485
|
479 |
subsubsection {* Finiteness *}
|
paulson@14485
|
480 |
|
paulson@15418
|
481 |
lemma image_atLeastZeroLessThan_int: "0 \<le> u ==>
|
nipkow@15045
|
482 |
{(0::int)..<u} = int ` {..<nat u}"
|
paulson@14485
|
483 |
apply (unfold image_def lessThan_def)
|
paulson@14485
|
484 |
apply auto
|
paulson@14485
|
485 |
apply (rule_tac x = "nat x" in exI)
|
paulson@14485
|
486 |
apply (auto simp add: zless_nat_conj zless_nat_eq_int_zless [THEN sym])
|
paulson@14485
|
487 |
done
|
paulson@14485
|
488 |
|
nipkow@15045
|
489 |
lemma finite_atLeastZeroLessThan_int: "finite {(0::int)..<u}"
|
paulson@14485
|
490 |
apply (case_tac "0 \<le> u")
|
paulson@14485
|
491 |
apply (subst image_atLeastZeroLessThan_int, assumption)
|
paulson@14485
|
492 |
apply (rule finite_imageI)
|
paulson@14485
|
493 |
apply auto
|
paulson@14485
|
494 |
done
|
paulson@14485
|
495 |
|
nipkow@15045
|
496 |
lemma finite_atLeastLessThan_int [iff]: "finite {l..<u::int}"
|
nipkow@15045
|
497 |
apply (subgoal_tac "(%x. x + l) ` {0..<u-l} = {l..<u}")
|
paulson@14485
|
498 |
apply (erule subst)
|
paulson@14485
|
499 |
apply (rule finite_imageI)
|
paulson@14485
|
500 |
apply (rule finite_atLeastZeroLessThan_int)
|
nipkow@16733
|
501 |
apply (rule image_add_int_atLeastLessThan)
|
paulson@14485
|
502 |
done
|
paulson@14485
|
503 |
|
paulson@15418
|
504 |
lemma finite_atLeastAtMost_int [iff]: "finite {l..(u::int)}"
|
paulson@14485
|
505 |
by (subst atLeastLessThanPlusOne_atLeastAtMost_int [THEN sym], simp)
|
paulson@14485
|
506 |
|
paulson@15418
|
507 |
lemma finite_greaterThanAtMost_int [iff]: "finite {l<..(u::int)}"
|
paulson@14485
|
508 |
by (subst atLeastPlusOneAtMost_greaterThanAtMost_int [THEN sym], simp)
|
paulson@14485
|
509 |
|
paulson@15418
|
510 |
lemma finite_greaterThanLessThan_int [iff]: "finite {l<..<u::int}"
|
paulson@14485
|
511 |
by (subst atLeastPlusOneLessThan_greaterThanLessThan_int [THEN sym], simp)
|
paulson@14485
|
512 |
|
nipkow@24853
|
513 |
|
paulson@14485
|
514 |
subsubsection {* Cardinality *}
|
paulson@14485
|
515 |
|
nipkow@15045
|
516 |
lemma card_atLeastZeroLessThan_int: "card {(0::int)..<u} = nat u"
|
paulson@14485
|
517 |
apply (case_tac "0 \<le> u")
|
paulson@14485
|
518 |
apply (subst image_atLeastZeroLessThan_int, assumption)
|
paulson@14485
|
519 |
apply (subst card_image)
|
paulson@14485
|
520 |
apply (auto simp add: inj_on_def)
|
paulson@14485
|
521 |
done
|
paulson@14485
|
522 |
|
nipkow@15045
|
523 |
lemma card_atLeastLessThan_int [simp]: "card {l..<u} = nat (u - l)"
|
nipkow@15045
|
524 |
apply (subgoal_tac "card {l..<u} = card {0..<u-l}")
|
paulson@14485
|
525 |
apply (erule ssubst, rule card_atLeastZeroLessThan_int)
|
nipkow@15045
|
526 |
apply (subgoal_tac "(%x. x + l) ` {0..<u-l} = {l..<u}")
|
paulson@14485
|
527 |
apply (erule subst)
|
paulson@14485
|
528 |
apply (rule card_image)
|
paulson@14485
|
529 |
apply (simp add: inj_on_def)
|
nipkow@16733
|
530 |
apply (rule image_add_int_atLeastLessThan)
|
paulson@14485
|
531 |
done
|
paulson@14485
|
532 |
|
paulson@14485
|
533 |
lemma card_atLeastAtMost_int [simp]: "card {l..u} = nat (u - l + 1)"
|
nipkow@29667
|
534 |
apply (subst atLeastLessThanPlusOne_atLeastAtMost_int [THEN sym])
|
nipkow@29667
|
535 |
apply (auto simp add: algebra_simps)
|
nipkow@29667
|
536 |
done
|
paulson@14485
|
537 |
|
paulson@15418
|
538 |
lemma card_greaterThanAtMost_int [simp]: "card {l<..u} = nat (u - l)"
|
nipkow@29667
|
539 |
by (subst atLeastPlusOneAtMost_greaterThanAtMost_int [THEN sym], simp)
|
paulson@14485
|
540 |
|
nipkow@15045
|
541 |
lemma card_greaterThanLessThan_int [simp]: "card {l<..<u} = nat (u - (l + 1))"
|
nipkow@29667
|
542 |
by (subst atLeastPlusOneLessThan_greaterThanLessThan_int [THEN sym], simp)
|
paulson@14485
|
543 |
|
bulwahn@27656
|
544 |
lemma finite_M_bounded_by_nat: "finite {k. P k \<and> k < (i::nat)}"
|
bulwahn@27656
|
545 |
proof -
|
bulwahn@27656
|
546 |
have "{k. P k \<and> k < i} \<subseteq> {..<i}" by auto
|
bulwahn@27656
|
547 |
with finite_lessThan[of "i"] show ?thesis by (simp add: finite_subset)
|
bulwahn@27656
|
548 |
qed
|
bulwahn@27656
|
549 |
|
bulwahn@27656
|
550 |
lemma card_less:
|
bulwahn@27656
|
551 |
assumes zero_in_M: "0 \<in> M"
|
bulwahn@27656
|
552 |
shows "card {k \<in> M. k < Suc i} \<noteq> 0"
|
bulwahn@27656
|
553 |
proof -
|
bulwahn@27656
|
554 |
from zero_in_M have "{k \<in> M. k < Suc i} \<noteq> {}" by auto
|
bulwahn@27656
|
555 |
with finite_M_bounded_by_nat show ?thesis by (auto simp add: card_eq_0_iff)
|
bulwahn@27656
|
556 |
qed
|
bulwahn@27656
|
557 |
|
bulwahn@27656
|
558 |
lemma card_less_Suc2: "0 \<notin> M \<Longrightarrow> card {k. Suc k \<in> M \<and> k < i} = card {k \<in> M. k < Suc i}"
|
bulwahn@27656
|
559 |
apply (rule card_bij_eq [of "Suc" _ _ "\<lambda>x. x - 1"])
|
bulwahn@27656
|
560 |
apply simp
|
bulwahn@27656
|
561 |
apply fastsimp
|
bulwahn@27656
|
562 |
apply auto
|
bulwahn@27656
|
563 |
apply (rule inj_on_diff_nat)
|
bulwahn@27656
|
564 |
apply auto
|
bulwahn@27656
|
565 |
apply (case_tac x)
|
bulwahn@27656
|
566 |
apply auto
|
bulwahn@27656
|
567 |
apply (case_tac xa)
|
bulwahn@27656
|
568 |
apply auto
|
bulwahn@27656
|
569 |
apply (case_tac xa)
|
bulwahn@27656
|
570 |
apply auto
|
bulwahn@27656
|
571 |
apply (auto simp add: finite_M_bounded_by_nat)
|
bulwahn@27656
|
572 |
done
|
bulwahn@27656
|
573 |
|
bulwahn@27656
|
574 |
lemma card_less_Suc:
|
bulwahn@27656
|
575 |
assumes zero_in_M: "0 \<in> M"
|
bulwahn@27656
|
576 |
shows "Suc (card {k. Suc k \<in> M \<and> k < i}) = card {k \<in> M. k < Suc i}"
|
bulwahn@27656
|
577 |
proof -
|
bulwahn@27656
|
578 |
from assms have a: "0 \<in> {k \<in> M. k < Suc i}" by simp
|
bulwahn@27656
|
579 |
hence c: "{k \<in> M. k < Suc i} = insert 0 ({k \<in> M. k < Suc i} - {0})"
|
bulwahn@27656
|
580 |
by (auto simp only: insert_Diff)
|
bulwahn@27656
|
581 |
have b: "{k \<in> M. k < Suc i} - {0} = {k \<in> M - {0}. k < Suc i}" by auto
|
bulwahn@27656
|
582 |
from finite_M_bounded_by_nat[of "\<lambda>x. x \<in> M" "Suc i"] have "Suc (card {k. Suc k \<in> M \<and> k < i}) = card (insert 0 ({k \<in> M. k < Suc i} - {0}))"
|
bulwahn@27656
|
583 |
apply (subst card_insert)
|
bulwahn@27656
|
584 |
apply simp_all
|
bulwahn@27656
|
585 |
apply (subst b)
|
bulwahn@27656
|
586 |
apply (subst card_less_Suc2[symmetric])
|
bulwahn@27656
|
587 |
apply simp_all
|
bulwahn@27656
|
588 |
done
|
bulwahn@27656
|
589 |
with c show ?thesis by simp
|
bulwahn@27656
|
590 |
qed
|
bulwahn@27656
|
591 |
|
paulson@14485
|
592 |
|
paulson@13850
|
593 |
subsection {*Lemmas useful with the summation operator setsum*}
|
paulson@13850
|
594 |
|
ballarin@16102
|
595 |
text {* For examples, see Algebra/poly/UnivPoly2.thy *}
|
ballarin@13735
|
596 |
|
wenzelm@14577
|
597 |
subsubsection {* Disjoint Unions *}
|
ballarin@13735
|
598 |
|
wenzelm@14577
|
599 |
text {* Singletons and open intervals *}
|
ballarin@13735
|
600 |
|
ballarin@13735
|
601 |
lemma ivl_disj_un_singleton:
|
nipkow@15045
|
602 |
"{l::'a::linorder} Un {l<..} = {l..}"
|
nipkow@15045
|
603 |
"{..<u} Un {u::'a::linorder} = {..u}"
|
nipkow@15045
|
604 |
"(l::'a::linorder) < u ==> {l} Un {l<..<u} = {l..<u}"
|
nipkow@15045
|
605 |
"(l::'a::linorder) < u ==> {l<..<u} Un {u} = {l<..u}"
|
nipkow@15045
|
606 |
"(l::'a::linorder) <= u ==> {l} Un {l<..u} = {l..u}"
|
nipkow@15045
|
607 |
"(l::'a::linorder) <= u ==> {l..<u} Un {u} = {l..u}"
|
ballarin@14398
|
608 |
by auto
|
ballarin@13735
|
609 |
|
wenzelm@14577
|
610 |
text {* One- and two-sided intervals *}
|
ballarin@13735
|
611 |
|
ballarin@13735
|
612 |
lemma ivl_disj_un_one:
|
nipkow@15045
|
613 |
"(l::'a::linorder) < u ==> {..l} Un {l<..<u} = {..<u}"
|
nipkow@15045
|
614 |
"(l::'a::linorder) <= u ==> {..<l} Un {l..<u} = {..<u}"
|
nipkow@15045
|
615 |
"(l::'a::linorder) <= u ==> {..l} Un {l<..u} = {..u}"
|
nipkow@15045
|
616 |
"(l::'a::linorder) <= u ==> {..<l} Un {l..u} = {..u}"
|
nipkow@15045
|
617 |
"(l::'a::linorder) <= u ==> {l<..u} Un {u<..} = {l<..}"
|
nipkow@15045
|
618 |
"(l::'a::linorder) < u ==> {l<..<u} Un {u..} = {l<..}"
|
nipkow@15045
|
619 |
"(l::'a::linorder) <= u ==> {l..u} Un {u<..} = {l..}"
|
nipkow@15045
|
620 |
"(l::'a::linorder) <= u ==> {l..<u} Un {u..} = {l..}"
|
ballarin@14398
|
621 |
by auto
|
ballarin@13735
|
622 |
|
wenzelm@14577
|
623 |
text {* Two- and two-sided intervals *}
|
ballarin@13735
|
624 |
|
ballarin@13735
|
625 |
lemma ivl_disj_un_two:
|
nipkow@15045
|
626 |
"[| (l::'a::linorder) < m; m <= u |] ==> {l<..<m} Un {m..<u} = {l<..<u}"
|
nipkow@15045
|
627 |
"[| (l::'a::linorder) <= m; m < u |] ==> {l<..m} Un {m<..<u} = {l<..<u}"
|
nipkow@15045
|
628 |
"[| (l::'a::linorder) <= m; m <= u |] ==> {l..<m} Un {m..<u} = {l..<u}"
|
nipkow@15045
|
629 |
"[| (l::'a::linorder) <= m; m < u |] ==> {l..m} Un {m<..<u} = {l..<u}"
|
nipkow@15045
|
630 |
"[| (l::'a::linorder) < m; m <= u |] ==> {l<..<m} Un {m..u} = {l<..u}"
|
nipkow@15045
|
631 |
"[| (l::'a::linorder) <= m; m <= u |] ==> {l<..m} Un {m<..u} = {l<..u}"
|
nipkow@15045
|
632 |
"[| (l::'a::linorder) <= m; m <= u |] ==> {l..<m} Un {m..u} = {l..u}"
|
nipkow@15045
|
633 |
"[| (l::'a::linorder) <= m; m <= u |] ==> {l..m} Un {m<..u} = {l..u}"
|
ballarin@14398
|
634 |
by auto
|
ballarin@13735
|
635 |
|
ballarin@13735
|
636 |
lemmas ivl_disj_un = ivl_disj_un_singleton ivl_disj_un_one ivl_disj_un_two
|
ballarin@13735
|
637 |
|
wenzelm@14577
|
638 |
subsubsection {* Disjoint Intersections *}
|
ballarin@13735
|
639 |
|
wenzelm@14577
|
640 |
text {* Singletons and open intervals *}
|
ballarin@13735
|
641 |
|
ballarin@13735
|
642 |
lemma ivl_disj_int_singleton:
|
nipkow@15045
|
643 |
"{l::'a::order} Int {l<..} = {}"
|
nipkow@15045
|
644 |
"{..<u} Int {u} = {}"
|
nipkow@15045
|
645 |
"{l} Int {l<..<u} = {}"
|
nipkow@15045
|
646 |
"{l<..<u} Int {u} = {}"
|
nipkow@15045
|
647 |
"{l} Int {l<..u} = {}"
|
nipkow@15045
|
648 |
"{l..<u} Int {u} = {}"
|
ballarin@13735
|
649 |
by simp+
|
ballarin@13735
|
650 |
|
wenzelm@14577
|
651 |
text {* One- and two-sided intervals *}
|
ballarin@13735
|
652 |
|
ballarin@13735
|
653 |
lemma ivl_disj_int_one:
|
nipkow@15045
|
654 |
"{..l::'a::order} Int {l<..<u} = {}"
|
nipkow@15045
|
655 |
"{..<l} Int {l..<u} = {}"
|
nipkow@15045
|
656 |
"{..l} Int {l<..u} = {}"
|
nipkow@15045
|
657 |
"{..<l} Int {l..u} = {}"
|
nipkow@15045
|
658 |
"{l<..u} Int {u<..} = {}"
|
nipkow@15045
|
659 |
"{l<..<u} Int {u..} = {}"
|
nipkow@15045
|
660 |
"{l..u} Int {u<..} = {}"
|
nipkow@15045
|
661 |
"{l..<u} Int {u..} = {}"
|
ballarin@14398
|
662 |
by auto
|
ballarin@13735
|
663 |
|
wenzelm@14577
|
664 |
text {* Two- and two-sided intervals *}
|
ballarin@13735
|
665 |
|
ballarin@13735
|
666 |
lemma ivl_disj_int_two:
|
nipkow@15045
|
667 |
"{l::'a::order<..<m} Int {m..<u} = {}"
|
nipkow@15045
|
668 |
"{l<..m} Int {m<..<u} = {}"
|
nipkow@15045
|
669 |
"{l..<m} Int {m..<u} = {}"
|
nipkow@15045
|
670 |
"{l..m} Int {m<..<u} = {}"
|
nipkow@15045
|
671 |
"{l<..<m} Int {m..u} = {}"
|
nipkow@15045
|
672 |
"{l<..m} Int {m<..u} = {}"
|
nipkow@15045
|
673 |
"{l..<m} Int {m..u} = {}"
|
nipkow@15045
|
674 |
"{l..m} Int {m<..u} = {}"
|
ballarin@14398
|
675 |
by auto
|
ballarin@13735
|
676 |
|
ballarin@13735
|
677 |
lemmas ivl_disj_int = ivl_disj_int_singleton ivl_disj_int_one ivl_disj_int_two
|
ballarin@13735
|
678 |
|
nipkow@15542
|
679 |
subsubsection {* Some Differences *}
|
nipkow@15542
|
680 |
|
nipkow@15542
|
681 |
lemma ivl_diff[simp]:
|
nipkow@15542
|
682 |
"i \<le> n \<Longrightarrow> {i..<m} - {i..<n} = {n..<(m::'a::linorder)}"
|
nipkow@15542
|
683 |
by(auto)
|
nipkow@15542
|
684 |
|
nipkow@15542
|
685 |
|
nipkow@15542
|
686 |
subsubsection {* Some Subset Conditions *}
|
nipkow@15542
|
687 |
|
paulson@24286
|
688 |
lemma ivl_subset [simp,noatp]:
|
nipkow@15542
|
689 |
"({i..<j} \<subseteq> {m..<n}) = (j \<le> i | m \<le> i & j \<le> (n::'a::linorder))"
|
nipkow@15542
|
690 |
apply(auto simp:linorder_not_le)
|
nipkow@15542
|
691 |
apply(rule ccontr)
|
nipkow@15542
|
692 |
apply(insert linorder_le_less_linear[of i n])
|
nipkow@15542
|
693 |
apply(clarsimp simp:linorder_not_le)
|
nipkow@15542
|
694 |
apply(fastsimp)
|
nipkow@15542
|
695 |
done
|
nipkow@15542
|
696 |
|
nipkow@15041
|
697 |
|
nipkow@15042
|
698 |
subsection {* Summation indexed over intervals *}
|
nipkow@15042
|
699 |
|
nipkow@15042
|
700 |
syntax
|
nipkow@15042
|
701 |
"_from_to_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(SUM _ = _.._./ _)" [0,0,0,10] 10)
|
nipkow@15048
|
702 |
"_from_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(SUM _ = _..<_./ _)" [0,0,0,10] 10)
|
nipkow@16052
|
703 |
"_upt_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(SUM _<_./ _)" [0,0,10] 10)
|
nipkow@16052
|
704 |
"_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(SUM _<=_./ _)" [0,0,10] 10)
|
nipkow@15042
|
705 |
syntax (xsymbols)
|
nipkow@15042
|
706 |
"_from_to_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_ = _.._./ _)" [0,0,0,10] 10)
|
nipkow@15048
|
707 |
"_from_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_ = _..<_./ _)" [0,0,0,10] 10)
|
nipkow@16052
|
708 |
"_upt_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_<_./ _)" [0,0,10] 10)
|
nipkow@16052
|
709 |
"_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_\<le>_./ _)" [0,0,10] 10)
|
nipkow@15042
|
710 |
syntax (HTML output)
|
nipkow@15042
|
711 |
"_from_to_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_ = _.._./ _)" [0,0,0,10] 10)
|
nipkow@15048
|
712 |
"_from_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_ = _..<_./ _)" [0,0,0,10] 10)
|
nipkow@16052
|
713 |
"_upt_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_<_./ _)" [0,0,10] 10)
|
nipkow@16052
|
714 |
"_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b" ("(3\<Sum>_\<le>_./ _)" [0,0,10] 10)
|
nipkow@15056
|
715 |
syntax (latex_sum output)
|
nipkow@15052
|
716 |
"_from_to_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b"
|
nipkow@15052
|
717 |
("(3\<^raw:$\sum_{>_ = _\<^raw:}^{>_\<^raw:}$> _)" [0,0,0,10] 10)
|
nipkow@15052
|
718 |
"_from_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b"
|
nipkow@15052
|
719 |
("(3\<^raw:$\sum_{>_ = _\<^raw:}^{<>_\<^raw:}$> _)" [0,0,0,10] 10)
|
nipkow@16052
|
720 |
"_upt_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b"
|
nipkow@16052
|
721 |
("(3\<^raw:$\sum_{>_ < _\<^raw:}$> _)" [0,0,10] 10)
|
nipkow@15052
|
722 |
"_upto_setsum" :: "idt \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> 'b"
|
nipkow@16052
|
723 |
("(3\<^raw:$\sum_{>_ \<le> _\<^raw:}$> _)" [0,0,10] 10)
|
nipkow@15042
|
724 |
|
nipkow@15048
|
725 |
translations
|
nipkow@28853
|
726 |
"\<Sum>x=a..b. t" == "CONST setsum (%x. t) {a..b}"
|
nipkow@28853
|
727 |
"\<Sum>x=a..<b. t" == "CONST setsum (%x. t) {a..<b}"
|
nipkow@28853
|
728 |
"\<Sum>i\<le>n. t" == "CONST setsum (\<lambda>i. t) {..n}"
|
nipkow@28853
|
729 |
"\<Sum>i<n. t" == "CONST setsum (\<lambda>i. t) {..<n}"
|
nipkow@15042
|
730 |
|
nipkow@15052
|
731 |
text{* The above introduces some pretty alternative syntaxes for
|
nipkow@15056
|
732 |
summation over intervals:
|
nipkow@15052
|
733 |
\begin{center}
|
nipkow@15052
|
734 |
\begin{tabular}{lll}
|
nipkow@15056
|
735 |
Old & New & \LaTeX\\
|
nipkow@15056
|
736 |
@{term[source]"\<Sum>x\<in>{a..b}. e"} & @{term"\<Sum>x=a..b. e"} & @{term[mode=latex_sum]"\<Sum>x=a..b. e"}\\
|
nipkow@15056
|
737 |
@{term[source]"\<Sum>x\<in>{a..<b}. e"} & @{term"\<Sum>x=a..<b. e"} & @{term[mode=latex_sum]"\<Sum>x=a..<b. e"}\\
|
nipkow@16052
|
738 |
@{term[source]"\<Sum>x\<in>{..b}. e"} & @{term"\<Sum>x\<le>b. e"} & @{term[mode=latex_sum]"\<Sum>x\<le>b. e"}\\
|
nipkow@15056
|
739 |
@{term[source]"\<Sum>x\<in>{..<b}. e"} & @{term"\<Sum>x<b. e"} & @{term[mode=latex_sum]"\<Sum>x<b. e"}
|
nipkow@15052
|
740 |
\end{tabular}
|
nipkow@15052
|
741 |
\end{center}
|
nipkow@15056
|
742 |
The left column shows the term before introduction of the new syntax,
|
nipkow@15056
|
743 |
the middle column shows the new (default) syntax, and the right column
|
nipkow@15056
|
744 |
shows a special syntax. The latter is only meaningful for latex output
|
nipkow@15056
|
745 |
and has to be activated explicitly by setting the print mode to
|
wenzelm@21502
|
746 |
@{text latex_sum} (e.g.\ via @{text "mode = latex_sum"} in
|
nipkow@15056
|
747 |
antiquotations). It is not the default \LaTeX\ output because it only
|
nipkow@15056
|
748 |
works well with italic-style formulae, not tt-style.
|
nipkow@15052
|
749 |
|
nipkow@15052
|
750 |
Note that for uniformity on @{typ nat} it is better to use
|
nipkow@15052
|
751 |
@{term"\<Sum>x::nat=0..<n. e"} rather than @{text"\<Sum>x<n. e"}: @{text setsum} may
|
nipkow@15052
|
752 |
not provide all lemmas available for @{term"{m..<n}"} also in the
|
nipkow@15052
|
753 |
special form for @{term"{..<n}"}. *}
|
nipkow@15052
|
754 |
|
nipkow@15542
|
755 |
text{* This congruence rule should be used for sums over intervals as
|
nipkow@15542
|
756 |
the standard theorem @{text[source]setsum_cong} does not work well
|
nipkow@15542
|
757 |
with the simplifier who adds the unsimplified premise @{term"x:B"} to
|
nipkow@15542
|
758 |
the context. *}
|
nipkow@15542
|
759 |
|
nipkow@15542
|
760 |
lemma setsum_ivl_cong:
|
nipkow@15542
|
761 |
"\<lbrakk>a = c; b = d; !!x. \<lbrakk> c \<le> x; x < d \<rbrakk> \<Longrightarrow> f x = g x \<rbrakk> \<Longrightarrow>
|
nipkow@15542
|
762 |
setsum f {a..<b} = setsum g {c..<d}"
|
nipkow@15542
|
763 |
by(rule setsum_cong, simp_all)
|
nipkow@15042
|
764 |
|
nipkow@16041
|
765 |
(* FIXME why are the following simp rules but the corresponding eqns
|
nipkow@16041
|
766 |
on intervals are not? *)
|
nipkow@16041
|
767 |
|
nipkow@16052
|
768 |
lemma setsum_atMost_Suc[simp]: "(\<Sum>i \<le> Suc n. f i) = (\<Sum>i \<le> n. f i) + f(Suc n)"
|
nipkow@16052
|
769 |
by (simp add:atMost_Suc add_ac)
|
nipkow@16052
|
770 |
|
nipkow@16041
|
771 |
lemma setsum_lessThan_Suc[simp]: "(\<Sum>i < Suc n. f i) = (\<Sum>i < n. f i) + f n"
|
nipkow@16041
|
772 |
by (simp add:lessThan_Suc add_ac)
|
nipkow@15041
|
773 |
|
nipkow@15911
|
774 |
lemma setsum_cl_ivl_Suc[simp]:
|
nipkow@15561
|
775 |
"setsum f {m..Suc n} = (if Suc n < m then 0 else setsum f {m..n} + f(Suc n))"
|
nipkow@15561
|
776 |
by (auto simp:add_ac atLeastAtMostSuc_conv)
|
nipkow@15561
|
777 |
|
nipkow@15911
|
778 |
lemma setsum_op_ivl_Suc[simp]:
|
nipkow@15561
|
779 |
"setsum f {m..<Suc n} = (if n < m then 0 else setsum f {m..<n} + f(n))"
|
nipkow@15561
|
780 |
by (auto simp:add_ac atLeastLessThanSuc)
|
nipkow@16041
|
781 |
(*
|
nipkow@15561
|
782 |
lemma setsum_cl_ivl_add_one_nat: "(n::nat) <= m + 1 ==>
|
nipkow@15561
|
783 |
(\<Sum>i=n..m+1. f i) = (\<Sum>i=n..m. f i) + f(m + 1)"
|
nipkow@15561
|
784 |
by (auto simp:add_ac atLeastAtMostSuc_conv)
|
nipkow@16041
|
785 |
*)
|
nipkow@28068
|
786 |
|
nipkow@28068
|
787 |
lemma setsum_head:
|
nipkow@28068
|
788 |
fixes n :: nat
|
nipkow@28068
|
789 |
assumes mn: "m <= n"
|
nipkow@28068
|
790 |
shows "(\<Sum>x\<in>{m..n}. P x) = P m + (\<Sum>x\<in>{m<..n}. P x)" (is "?lhs = ?rhs")
|
nipkow@28068
|
791 |
proof -
|
nipkow@28068
|
792 |
from mn
|
nipkow@28068
|
793 |
have "{m..n} = {m} \<union> {m<..n}"
|
nipkow@28068
|
794 |
by (auto intro: ivl_disj_un_singleton)
|
nipkow@28068
|
795 |
hence "?lhs = (\<Sum>x\<in>{m} \<union> {m<..n}. P x)"
|
nipkow@28068
|
796 |
by (simp add: atLeast0LessThan)
|
nipkow@28068
|
797 |
also have "\<dots> = ?rhs" by simp
|
nipkow@28068
|
798 |
finally show ?thesis .
|
nipkow@28068
|
799 |
qed
|
nipkow@28068
|
800 |
|
nipkow@28068
|
801 |
lemma setsum_head_Suc:
|
nipkow@28068
|
802 |
"m \<le> n \<Longrightarrow> setsum f {m..n} = f m + setsum f {Suc m..n}"
|
nipkow@28068
|
803 |
by (simp add: setsum_head atLeastSucAtMost_greaterThanAtMost)
|
nipkow@28068
|
804 |
|
nipkow@28068
|
805 |
lemma setsum_head_upt_Suc:
|
nipkow@28068
|
806 |
"m < n \<Longrightarrow> setsum f {m..<n} = f m + setsum f {Suc m..<n}"
|
nipkow@28068
|
807 |
apply(insert setsum_head_Suc[of m "n - 1" f])
|
nipkow@29667
|
808 |
apply (simp add: atLeastLessThanSuc_atLeastAtMost[symmetric] algebra_simps)
|
nipkow@28068
|
809 |
done
|
nipkow@28068
|
810 |
|
nipkow@28068
|
811 |
|
nipkow@15539
|
812 |
lemma setsum_add_nat_ivl: "\<lbrakk> m \<le> n; n \<le> p \<rbrakk> \<Longrightarrow>
|
nipkow@15539
|
813 |
setsum f {m..<n} + setsum f {n..<p} = setsum f {m..<p::nat}"
|
nipkow@15539
|
814 |
by (simp add:setsum_Un_disjoint[symmetric] ivl_disj_int ivl_disj_un)
|
nipkow@15539
|
815 |
|
nipkow@15539
|
816 |
lemma setsum_diff_nat_ivl:
|
nipkow@15539
|
817 |
fixes f :: "nat \<Rightarrow> 'a::ab_group_add"
|
nipkow@15539
|
818 |
shows "\<lbrakk> m \<le> n; n \<le> p \<rbrakk> \<Longrightarrow>
|
nipkow@15539
|
819 |
setsum f {m..<p} - setsum f {m..<n} = setsum f {n..<p}"
|
nipkow@15539
|
820 |
using setsum_add_nat_ivl [of m n p f,symmetric]
|
nipkow@15539
|
821 |
apply (simp add: add_ac)
|
nipkow@15539
|
822 |
done
|
nipkow@15539
|
823 |
|
nipkow@28068
|
824 |
|
nipkow@16733
|
825 |
subsection{* Shifting bounds *}
|
nipkow@16733
|
826 |
|
nipkow@15539
|
827 |
lemma setsum_shift_bounds_nat_ivl:
|
nipkow@15539
|
828 |
"setsum f {m+k..<n+k} = setsum (%i. f(i + k)){m..<n::nat}"
|
nipkow@15539
|
829 |
by (induct "n", auto simp:atLeastLessThanSuc)
|
nipkow@15539
|
830 |
|
nipkow@16733
|
831 |
lemma setsum_shift_bounds_cl_nat_ivl:
|
nipkow@16733
|
832 |
"setsum f {m+k..n+k} = setsum (%i. f(i + k)){m..n::nat}"
|
nipkow@16733
|
833 |
apply (insert setsum_reindex[OF inj_on_add_nat, where h=f and B = "{m..n}"])
|
nipkow@16733
|
834 |
apply (simp add:image_add_atLeastAtMost o_def)
|
nipkow@16733
|
835 |
done
|
nipkow@16733
|
836 |
|
nipkow@16733
|
837 |
corollary setsum_shift_bounds_cl_Suc_ivl:
|
nipkow@16733
|
838 |
"setsum f {Suc m..Suc n} = setsum (%i. f(Suc i)){m..n}"
|
nipkow@16733
|
839 |
by (simp add:setsum_shift_bounds_cl_nat_ivl[where k=1,simplified])
|
nipkow@16733
|
840 |
|
nipkow@16733
|
841 |
corollary setsum_shift_bounds_Suc_ivl:
|
nipkow@16733
|
842 |
"setsum f {Suc m..<Suc n} = setsum (%i. f(Suc i)){m..<n}"
|
nipkow@16733
|
843 |
by (simp add:setsum_shift_bounds_nat_ivl[where k=1,simplified])
|
nipkow@16733
|
844 |
|
nipkow@28068
|
845 |
lemma setsum_shift_lb_Suc0_0:
|
nipkow@28068
|
846 |
"f(0::nat) = (0::nat) \<Longrightarrow> setsum f {Suc 0..k} = setsum f {0..k}"
|
nipkow@28068
|
847 |
by(simp add:setsum_head_Suc)
|
kleing@19106
|
848 |
|
nipkow@28068
|
849 |
lemma setsum_shift_lb_Suc0_0_upt:
|
nipkow@28068
|
850 |
"f(0::nat) = 0 \<Longrightarrow> setsum f {Suc 0..<k} = setsum f {0..<k}"
|
nipkow@28068
|
851 |
apply(cases k)apply simp
|
nipkow@28068
|
852 |
apply(simp add:setsum_head_upt_Suc)
|
nipkow@28068
|
853 |
done
|
kleing@19022
|
854 |
|
ballarin@17149
|
855 |
subsection {* The formula for geometric sums *}
|
ballarin@17149
|
856 |
|
ballarin@17149
|
857 |
lemma geometric_sum:
|
ballarin@17149
|
858 |
"x ~= 1 ==> (\<Sum>i=0..<n. x ^ i) =
|
huffman@22713
|
859 |
(x ^ n - 1) / (x - 1::'a::{field, recpower})"
|
nipkow@23496
|
860 |
by (induct "n") (simp_all add:field_simps power_Suc)
|
ballarin@17149
|
861 |
|
kleing@19469
|
862 |
subsection {* The formula for arithmetic sums *}
|
kleing@19469
|
863 |
|
kleing@19469
|
864 |
lemma gauss_sum:
|
huffman@23277
|
865 |
"((1::'a::comm_semiring_1) + 1)*(\<Sum>i\<in>{1..n}. of_nat i) =
|
kleing@19469
|
866 |
of_nat n*((of_nat n)+1)"
|
kleing@19469
|
867 |
proof (induct n)
|
kleing@19469
|
868 |
case 0
|
kleing@19469
|
869 |
show ?case by simp
|
kleing@19469
|
870 |
next
|
kleing@19469
|
871 |
case (Suc n)
|
nipkow@29667
|
872 |
then show ?case by (simp add: algebra_simps)
|
kleing@19469
|
873 |
qed
|
kleing@19469
|
874 |
|
kleing@19469
|
875 |
theorem arith_series_general:
|
huffman@23277
|
876 |
"((1::'a::comm_semiring_1) + 1) * (\<Sum>i\<in>{..<n}. a + of_nat i * d) =
|
kleing@19469
|
877 |
of_nat n * (a + (a + of_nat(n - 1)*d))"
|
kleing@19469
|
878 |
proof cases
|
kleing@19469
|
879 |
assume ngt1: "n > 1"
|
kleing@19469
|
880 |
let ?I = "\<lambda>i. of_nat i" and ?n = "of_nat n"
|
kleing@19469
|
881 |
have
|
kleing@19469
|
882 |
"(\<Sum>i\<in>{..<n}. a+?I i*d) =
|
kleing@19469
|
883 |
((\<Sum>i\<in>{..<n}. a) + (\<Sum>i\<in>{..<n}. ?I i*d))"
|
kleing@19469
|
884 |
by (rule setsum_addf)
|
kleing@19469
|
885 |
also from ngt1 have "\<dots> = ?n*a + (\<Sum>i\<in>{..<n}. ?I i*d)" by simp
|
kleing@19469
|
886 |
also from ngt1 have "\<dots> = (?n*a + d*(\<Sum>i\<in>{1..<n}. ?I i))"
|
nipkow@28068
|
887 |
by (simp add: setsum_right_distrib atLeast0LessThan[symmetric] setsum_shift_lb_Suc0_0_upt mult_ac)
|
kleing@19469
|
888 |
also have "(1+1)*\<dots> = (1+1)*?n*a + d*(1+1)*(\<Sum>i\<in>{1..<n}. ?I i)"
|
kleing@19469
|
889 |
by (simp add: left_distrib right_distrib)
|
kleing@19469
|
890 |
also from ngt1 have "{1..<n} = {1..n - 1}"
|
nipkow@28068
|
891 |
by (cases n) (auto simp: atLeastLessThanSuc_atLeastAtMost)
|
nipkow@28068
|
892 |
also from ngt1
|
kleing@19469
|
893 |
have "(1+1)*?n*a + d*(1+1)*(\<Sum>i\<in>{1..n - 1}. ?I i) = ((1+1)*?n*a + d*?I (n - 1)*?I n)"
|
kleing@19469
|
894 |
by (simp only: mult_ac gauss_sum [of "n - 1"])
|
huffman@23431
|
895 |
(simp add: mult_ac trans [OF add_commute of_nat_Suc [symmetric]])
|
nipkow@29667
|
896 |
finally show ?thesis by (simp add: algebra_simps)
|
kleing@19469
|
897 |
next
|
kleing@19469
|
898 |
assume "\<not>(n > 1)"
|
kleing@19469
|
899 |
hence "n = 1 \<or> n = 0" by auto
|
nipkow@29667
|
900 |
thus ?thesis by (auto simp: algebra_simps)
|
kleing@19469
|
901 |
qed
|
kleing@19469
|
902 |
|
kleing@19469
|
903 |
lemma arith_series_nat:
|
kleing@19469
|
904 |
"Suc (Suc 0) * (\<Sum>i\<in>{..<n}. a+i*d) = n * (a + (a+(n - 1)*d))"
|
kleing@19469
|
905 |
proof -
|
kleing@19469
|
906 |
have
|
kleing@19469
|
907 |
"((1::nat) + 1) * (\<Sum>i\<in>{..<n::nat}. a + of_nat(i)*d) =
|
kleing@19469
|
908 |
of_nat(n) * (a + (a + of_nat(n - 1)*d))"
|
kleing@19469
|
909 |
by (rule arith_series_general)
|
kleing@19469
|
910 |
thus ?thesis by (auto simp add: of_nat_id)
|
kleing@19469
|
911 |
qed
|
kleing@19469
|
912 |
|
kleing@19469
|
913 |
lemma arith_series_int:
|
kleing@19469
|
914 |
"(2::int) * (\<Sum>i\<in>{..<n}. a + of_nat i * d) =
|
kleing@19469
|
915 |
of_nat n * (a + (a + of_nat(n - 1)*d))"
|
kleing@19469
|
916 |
proof -
|
kleing@19469
|
917 |
have
|
kleing@19469
|
918 |
"((1::int) + 1) * (\<Sum>i\<in>{..<n}. a + of_nat i * d) =
|
kleing@19469
|
919 |
of_nat(n) * (a + (a + of_nat(n - 1)*d))"
|
kleing@19469
|
920 |
by (rule arith_series_general)
|
kleing@19469
|
921 |
thus ?thesis by simp
|
kleing@19469
|
922 |
qed
|
paulson@15418
|
923 |
|
kleing@19022
|
924 |
lemma sum_diff_distrib:
|
kleing@19022
|
925 |
fixes P::"nat\<Rightarrow>nat"
|
kleing@19022
|
926 |
shows
|
kleing@19022
|
927 |
"\<forall>x. Q x \<le> P x \<Longrightarrow>
|
kleing@19022
|
928 |
(\<Sum>x<n. P x) - (\<Sum>x<n. Q x) = (\<Sum>x<n. P x - Q x)"
|
kleing@19022
|
929 |
proof (induct n)
|
kleing@19022
|
930 |
case 0 show ?case by simp
|
kleing@19022
|
931 |
next
|
kleing@19022
|
932 |
case (Suc n)
|
kleing@19022
|
933 |
|
kleing@19022
|
934 |
let ?lhs = "(\<Sum>x<n. P x) - (\<Sum>x<n. Q x)"
|
kleing@19022
|
935 |
let ?rhs = "\<Sum>x<n. P x - Q x"
|
kleing@19022
|
936 |
|
kleing@19022
|
937 |
from Suc have "?lhs = ?rhs" by simp
|
kleing@19022
|
938 |
moreover
|
kleing@19022
|
939 |
from Suc have "?lhs + P n - Q n = ?rhs + (P n - Q n)" by simp
|
kleing@19022
|
940 |
moreover
|
kleing@19022
|
941 |
from Suc have
|
kleing@19022
|
942 |
"(\<Sum>x<n. P x) + P n - ((\<Sum>x<n. Q x) + Q n) = ?rhs + (P n - Q n)"
|
kleing@19022
|
943 |
by (subst diff_diff_left[symmetric],
|
kleing@19022
|
944 |
subst diff_add_assoc2)
|
kleing@19022
|
945 |
(auto simp: diff_add_assoc2 intro: setsum_mono)
|
kleing@19022
|
946 |
ultimately
|
kleing@19022
|
947 |
show ?case by simp
|
kleing@19022
|
948 |
qed
|
kleing@19022
|
949 |
|
nipkow@8924
|
950 |
end
|