src/HOL/Library/Liminf_Limsup.thy
changeset 61585 a9599d3d7610
parent 61245 b77bf45efe21
child 61730 2b775b888897
equal deleted inserted replaced
61584:f06e5a5a4b46 61585:a9599d3d7610
    28 lemma INF_pair:
    28 lemma INF_pair:
    29   fixes f :: "_ \<Rightarrow> _ \<Rightarrow> _ :: complete_lattice"
    29   fixes f :: "_ \<Rightarrow> _ \<Rightarrow> _ :: complete_lattice"
    30   shows "(INF i : A. INF j : B. f i j) = (INF p : A \<times> B. f (fst p) (snd p))"
    30   shows "(INF i : A. INF j : B. f i j) = (INF p : A \<times> B. f (fst p) (snd p))"
    31   by (rule antisym) (auto intro!: INF_greatest INF_lower2)
    31   by (rule antisym) (auto intro!: INF_greatest INF_lower2)
    32 
    32 
    33 subsubsection \<open>@{text Liminf} and @{text Limsup}\<close>
    33 subsubsection \<open>\<open>Liminf\<close> and \<open>Limsup\<close>\<close>
    34 
    34 
    35 definition Liminf :: "'a filter \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> 'b :: complete_lattice" where
    35 definition Liminf :: "'a filter \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> 'b :: complete_lattice" where
    36   "Liminf F f = (SUP P:{P. eventually P F}. INF x:{x. P x}. f x)"
    36   "Liminf F f = (SUP P:{P. eventually P F}. INF x:{x. P x}. f x)"
    37 
    37 
    38 definition Limsup :: "'a filter \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> 'b :: complete_lattice" where
    38 definition Limsup :: "'a filter \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> 'b :: complete_lattice" where