src/HOL/Metis_Examples/BigO.thy
changeset 35416 d8d7d1b785af
parent 35050 9f841f20dca6
child 36067 3a074096f83a
equal deleted inserted replaced
35342:4dc65845eab3 35416:d8d7d1b785af
  1097   apply (simp add: fun_diff_def)
  1097   apply (simp add: fun_diff_def)
  1098 done
  1098 done
  1099 
  1099 
  1100 subsection {* Less than or equal to *}
  1100 subsection {* Less than or equal to *}
  1101 
  1101 
  1102 constdefs 
  1102 definition lesso :: "('a => 'b::linordered_idom) => ('a => 'b) => ('a => 'b)" (infixl "<o" 70) where
  1103   lesso :: "('a => 'b::linordered_idom) => ('a => 'b) => ('a => 'b)"
       
  1104       (infixl "<o" 70)
       
  1105   "f <o g == (%x. max (f x - g x) 0)"
  1103   "f <o g == (%x. max (f x - g x) 0)"
  1106 
  1104 
  1107 lemma bigo_lesseq1: "f =o O(h) ==> ALL x. abs (g x) <= abs (f x) ==>
  1105 lemma bigo_lesseq1: "f =o O(h) ==> ALL x. abs (g x) <= abs (f x) ==>
  1108     g =o O(h)"
  1106     g =o O(h)"
  1109   apply (unfold bigo_def)
  1107   apply (unfold bigo_def)