src/HOL/Analysis/Equivalence_Lebesgue_Henstock_Integration.thy
changeset 68072 493b818e8e10
parent 67998 73a5a33486ee
child 68073 fad29d2a17a5
equal deleted inserted replaced
68001:0a2a1b6507c1 68072:493b818e8e10
  1224   obtain a where "a \<noteq> 0" and a: "span S \<subseteq> {x. a \<bullet> x = 0}"
  1224   obtain a where "a \<noteq> 0" and a: "span S \<subseteq> {x. a \<bullet> x = 0}"
  1225     using lowdim_subset_hyperplane [OF assms] by blast
  1225     using lowdim_subset_hyperplane [OF assms] by blast
  1226   have "negligible (span S)"
  1226   have "negligible (span S)"
  1227     using \<open>a \<noteq> 0\<close> a negligible_hyperplane by (blast intro: negligible_subset)
  1227     using \<open>a \<noteq> 0\<close> a negligible_hyperplane by (blast intro: negligible_subset)
  1228   then show ?thesis
  1228   then show ?thesis
  1229     using span_inc by (blast intro: negligible_subset)
  1229     using span_base by (blast intro: negligible_subset)
  1230 qed
  1230 qed
  1231 
  1231 
  1232 proposition negligible_convex_frontier:
  1232 proposition negligible_convex_frontier:
  1233   fixes S :: "'N :: euclidean_space set"
  1233   fixes S :: "'N :: euclidean_space set"
  1234   assumes "convex S"
  1234   assumes "convex S"
  1238   proof -
  1238   proof -
  1239     obtain B where "B \<subseteq> S" and indB: "independent B"
  1239     obtain B where "B \<subseteq> S" and indB: "independent B"
  1240                and spanB: "S \<subseteq> span B" and cardB: "card B = dim S"
  1240                and spanB: "S \<subseteq> span B" and cardB: "card B = dim S"
  1241       by (metis basis_exists)
  1241       by (metis basis_exists)
  1242     consider "dim S < DIM('N)" | "dim S = DIM('N)"
  1242     consider "dim S < DIM('N)" | "dim S = DIM('N)"
  1243       using dim_subset_UNIV le_eq_less_or_eq by blast
  1243       using dim_subset_UNIV le_eq_less_or_eq by auto
  1244     then show ?thesis
  1244     then show ?thesis
  1245     proof cases
  1245     proof cases
  1246       case 1
  1246       case 1
  1247       show ?thesis
  1247       show ?thesis
  1248         by (rule negligible_subset [of "closure S"])
  1248         by (rule negligible_subset [of "closure S"])
  2846           have "negligible (frontier(g ` K \<inter> g ` L) \<union> interior(g ` K \<inter> g ` L))"
  2846           have "negligible (frontier(g ` K \<inter> g ` L) \<union> interior(g ` K \<inter> g ` L))"
  2847           proof (rule negligible_Un)
  2847           proof (rule negligible_Un)
  2848             show "negligible (frontier (g ` K \<inter> g ` L))"
  2848             show "negligible (frontier (g ` K \<inter> g ` L))"
  2849               by (simp add: negligible_convex_frontier convex_Int conv convex_linear_image that)
  2849               by (simp add: negligible_convex_frontier convex_Int conv convex_linear_image that)
  2850           next
  2850           next
  2851             show "negligible (interior (g ` K \<inter> g ` L))"
  2851             have "\<forall>p N. pairwise p N = (\<forall>Na. (Na::'n set) \<in> N \<longrightarrow> (\<forall>Nb. Nb \<in> N \<and> Na \<noteq> Nb \<longrightarrow> p Na Nb))"
  2852               by (metis (mono_tags, lifting) True finite.emptyI image_Int image_empty interior_Int interior_injective_linear_image intint negligible_finite pairwiseD that)
  2852               by (metis pairwise_def)
       
  2853             then have "interior K \<inter> interior L = {}"
       
  2854               using intint that(2) that(3) that(4) by presburger
       
  2855             then show "negligible (interior (g ` K \<inter> g ` L))"
       
  2856               by (metis True empty_imp_negligible image_Int image_empty interior_Int interior_injective_linear_image that(1))
  2853           qed
  2857           qed
  2854           moreover have "g ` K \<inter> g ` L \<subseteq> frontier (g ` K \<inter> g ` L) \<union> interior (g ` K \<inter> g ` L)"
  2858           moreover have "g ` K \<inter> g ` L \<subseteq> frontier (g ` K \<inter> g ` L) \<union> interior (g ` K \<inter> g ` L)"
  2855             apply (auto simp: frontier_def)
  2859             apply (auto simp: frontier_def)
  2856             using closure_subset contra_subsetD by fastforce+
  2860             using closure_subset contra_subsetD by fastforce+
  2857           ultimately show ?thesis
  2861           ultimately show ?thesis
  3174 lemma absolutely_integrable_norm:
  3178 lemma absolutely_integrable_norm:
  3175   fixes f :: "'a :: euclidean_space \<Rightarrow> 'b :: euclidean_space"
  3179   fixes f :: "'a :: euclidean_space \<Rightarrow> 'b :: euclidean_space"
  3176   assumes "f absolutely_integrable_on S"
  3180   assumes "f absolutely_integrable_on S"
  3177   shows "(norm o f) absolutely_integrable_on S"
  3181   shows "(norm o f) absolutely_integrable_on S"
  3178   using assms by (simp add: absolutely_integrable_on_def o_def)
  3182   using assms by (simp add: absolutely_integrable_on_def o_def)
  3179     
  3183 
  3180 lemma absolutely_integrable_abs:
  3184 lemma absolutely_integrable_abs:
  3181   fixes f :: "'a :: euclidean_space \<Rightarrow> 'b :: euclidean_space"
  3185   fixes f :: "'a :: euclidean_space \<Rightarrow> 'b :: euclidean_space"
  3182   assumes "f absolutely_integrable_on S"
  3186   assumes "f absolutely_integrable_on S"
  3183   shows "(\<lambda>x. \<Sum>i\<in>Basis. \<bar>f x \<bullet> i\<bar> *\<^sub>R i) absolutely_integrable_on S"
  3187   shows "(\<lambda>x. \<Sum>i\<in>Basis. \<bar>f x \<bullet> i\<bar> *\<^sub>R i) absolutely_integrable_on S"
  3184         (is "?g absolutely_integrable_on S")
  3188         (is "?g absolutely_integrable_on S")