src/HOL/Library/Indicator_Function.thy
changeset 58729 e8ecc79aee43
parent 57447 87429bdecad5
child 58881 b9556a055632
equal deleted inserted replaced
58728:42398b610f86 58729:e8ecc79aee43
    85   then have 
    85   then have 
    86     "\<And>n. (indicator (A (n + i)) x :: 'a) = 1"
    86     "\<And>n. (indicator (A (n + i)) x :: 'a) = 1"
    87     "(indicator (\<Union> i. A i) x :: 'a) = 1"
    87     "(indicator (\<Union> i. A i) x :: 'a) = 1"
    88     using incseqD[OF `incseq A`, of i "n + i" for n] `x \<in> A i` by (auto simp: indicator_def)
    88     using incseqD[OF `incseq A`, of i "n + i" for n] `x \<in> A i` by (auto simp: indicator_def)
    89   then show ?thesis
    89   then show ?thesis
    90     by (rule_tac LIMSEQ_offset[of _ i]) (simp add: tendsto_const)
    90     by (rule_tac LIMSEQ_offset[of _ i]) simp
    91 qed (auto simp: indicator_def tendsto_const)
    91 qed (auto simp: indicator_def)
    92 
    92 
    93 lemma LIMSEQ_indicator_UN:
    93 lemma LIMSEQ_indicator_UN:
    94   "(\<lambda>k. indicator (\<Union> i<k. A i) x :: 'a :: {topological_space, one, zero}) ----> indicator (\<Union>i. A i) x"
    94   "(\<lambda>k. indicator (\<Union> i<k. A i) x :: 'a :: {topological_space, one, zero}) ----> indicator (\<Union>i. A i) x"
    95 proof -
    95 proof -
    96   have "(\<lambda>k. indicator (\<Union> i<k. A i) x::'a) ----> indicator (\<Union>k. \<Union> i<k. A i) x"
    96   have "(\<lambda>k. indicator (\<Union> i<k. A i) x::'a) ----> indicator (\<Union>k. \<Union> i<k. A i) x"
   110   then have 
   110   then have 
   111     "\<And>n. (indicator (A (n + i)) x :: 'a) = 0"
   111     "\<And>n. (indicator (A (n + i)) x :: 'a) = 0"
   112     "(indicator (\<Inter>i. A i) x :: 'a) = 0"
   112     "(indicator (\<Inter>i. A i) x :: 'a) = 0"
   113     using decseqD[OF `decseq A`, of i "n + i" for n] `x \<notin> A i` by (auto simp: indicator_def)
   113     using decseqD[OF `decseq A`, of i "n + i" for n] `x \<notin> A i` by (auto simp: indicator_def)
   114   then show ?thesis
   114   then show ?thesis
   115     by (rule_tac LIMSEQ_offset[of _ i]) (simp add: tendsto_const)
   115     by (rule_tac LIMSEQ_offset[of _ i]) simp
   116 qed (auto simp: indicator_def tendsto_const)
   116 qed (auto simp: indicator_def)
   117 
   117 
   118 lemma LIMSEQ_indicator_INT:
   118 lemma LIMSEQ_indicator_INT:
   119   "(\<lambda>k. indicator (\<Inter>i<k. A i) x :: 'a :: {topological_space, one, zero}) ----> indicator (\<Inter>i. A i) x"
   119   "(\<lambda>k. indicator (\<Inter>i<k. A i) x :: 'a :: {topological_space, one, zero}) ----> indicator (\<Inter>i. A i) x"
   120 proof -
   120 proof -
   121   have "(\<lambda>k. indicator (\<Inter>i<k. A i) x::'a) ----> indicator (\<Inter>k. \<Inter>i<k. A i) x"
   121   have "(\<lambda>k. indicator (\<Inter>i<k. A i) x::'a) ----> indicator (\<Inter>k. \<Inter>i<k. A i) x"