src/HOL/Analysis/Nonnegative_Lebesgue_Integration.thy
changeset 76055 8d56461f85ec
parent 74362 0135a0c77b64
child 79583 a521c241e946
equal deleted inserted replaced
76054:a4b47c684445 76055:8d56461f85ec
  1381 qed
  1381 qed
  1382 
  1382 
  1383 lemma nn_integral_monotone_convergence_INF_decseq:
  1383 lemma nn_integral_monotone_convergence_INF_decseq:
  1384   assumes f: "decseq f" and *: "\<And>i. f i \<in> borel_measurable M" "(\<integral>\<^sup>+ x. f i x \<partial>M) < \<infinity>"
  1384   assumes f: "decseq f" and *: "\<And>i. f i \<in> borel_measurable M" "(\<integral>\<^sup>+ x. f i x \<partial>M) < \<infinity>"
  1385   shows "(\<integral>\<^sup>+ x. (INF i. f i x) \<partial>M) = (INF i. integral\<^sup>N M (f i))"
  1385   shows "(\<integral>\<^sup>+ x. (INF i. f i x) \<partial>M) = (INF i. integral\<^sup>N M (f i))"
  1386   using nn_integral_monotone_convergence_INF_AE[of f M i, OF _ *] f by (auto simp: decseq_Suc_iff le_fun_def)
  1386   using nn_integral_monotone_convergence_INF_AE[of f M i, OF _ *] f by (simp add: decseq_SucD le_funD)
  1387 
  1387 
  1388 theorem nn_integral_liminf:
  1388 theorem nn_integral_liminf:
  1389   fixes u :: "nat \<Rightarrow> 'a \<Rightarrow> ennreal"
  1389   fixes u :: "nat \<Rightarrow> 'a \<Rightarrow> ennreal"
  1390   assumes u: "\<And>i. u i \<in> borel_measurable M"
  1390   assumes u: "\<And>i. u i \<in> borel_measurable M"
  1391   shows "(\<integral>\<^sup>+ x. liminf (\<lambda>n. u n x) \<partial>M) \<le> liminf (\<lambda>n. integral\<^sup>N M (u n))"
  1391   shows "(\<integral>\<^sup>+ x. liminf (\<lambda>n. u n x) \<partial>M) \<le> liminf (\<lambda>n. integral\<^sup>N M (u n))"
  1462   unfolding inf_continuous_def
  1462   unfolding inf_continuous_def
  1463 proof safe
  1463 proof safe
  1464   fix C :: "nat \<Rightarrow> 'b" assume C: "decseq C"
  1464   fix C :: "nat \<Rightarrow> 'b" assume C: "decseq C"
  1465   then show "(\<integral>\<^sup>+ y. f y (Inf (C ` UNIV)) \<partial>M) = (INF i. \<integral>\<^sup>+ y. f y (C i) \<partial>M)"
  1465   then show "(\<integral>\<^sup>+ y. f y (Inf (C ` UNIV)) \<partial>M) = (INF i. \<integral>\<^sup>+ y. f y (C i) \<partial>M)"
  1466     using inf_continuous_mono[OF f] bnd
  1466     using inf_continuous_mono[OF f] bnd
  1467     by (auto simp add: inf_continuousD[OF f C] fun_eq_iff antimono_def mono_def le_fun_def less_top
  1467     by (auto simp add: inf_continuousD[OF f C] fun_eq_iff monotone_def le_fun_def less_top
  1468              intro!: nn_integral_monotone_convergence_INF_decseq)
  1468              intro!: nn_integral_monotone_convergence_INF_decseq)
  1469 qed
  1469 qed
  1470 
  1470 
  1471 lemma nn_integral_null_set:
  1471 lemma nn_integral_null_set:
  1472   assumes "N \<in> null_sets M" shows "(\<integral>\<^sup>+ x. u x * indicator N x \<partial>M) = 0"
  1472   assumes "N \<in> null_sets M" shows "(\<integral>\<^sup>+ x. u x * indicator N x \<partial>M) = 0"