diff --git a/CHANGELOG_UNRELEASED.md b/CHANGELOG_UNRELEASED.md index da48081bf..c3300c2f6 100644 --- a/CHANGELOG_UNRELEASED.md +++ b/CHANGELOG_UNRELEASED.md @@ -44,6 +44,10 @@ - in `lebesgue_measure.v`: + lemma `measurable_powRr` +- in `measure.v`: + + definition `discrete_measurable` + + lemmas `discrete_measurable0`, `discrete_measurableC`, `discrete_measurableU` + ### Changed - in `lebesgue_integrale.v` diff --git a/theories/measure.v b/theories/measure.v index 9b4e488c4..b16befccb 100644 --- a/theories/measure.v +++ b/theories/measure.v @@ -45,12 +45,7 @@ From HB Require Import structures. (* *) (* ## Instances of mathematical structures *) (* ``` *) -(* discrete_measurable_unit == the measurableType corresponding to *) -(* [set: set unit] *) -(* discrete_measurable_bool == the measurableType corresponding to *) -(* [set: set bool] *) -(* discrete_measurable_nat == the measurableType corresponding to *) -(* [set: set nat] *) +(* discrete_measurable T == alias for the sigma-algebra [set: set T] *) (* setring G == the set of sets G contains the empty set, is *) (* closed by union, and difference (it is a ring *) (* of sets in the sense of ringOfSetsType) *) @@ -1420,67 +1415,35 @@ Qed. End measurable_lemmas. -Section discrete_measurable_unit. - -Definition discrete_measurable_unit : set (set unit) := [set: set unit]. +Section discrete_measurable. +Context {T : Type}. -Let discrete_measurable0 : discrete_measurable_unit set0. Proof. by []. Qed. +Definition discrete_measurable : set (set T) := [set: set T]. -Let discrete_measurableC X : - discrete_measurable_unit X -> discrete_measurable_unit (~` X). -Proof. by []. Qed. +Lemma discrete_measurable0 : discrete_measurable set0. Proof. by []. Qed. -Let discrete_measurableU (F : (set unit)^nat) : - (forall i, discrete_measurable_unit (F i)) -> - discrete_measurable_unit (\bigcup_i F i). +Lemma discrete_measurableC X : + discrete_measurable X -> discrete_measurable (~` X). Proof. by []. Qed. -HB.instance Definition _ := @isMeasurable.Build default_measure_display unit - discrete_measurable_unit discrete_measurable0 - discrete_measurableC discrete_measurableU. - -End discrete_measurable_unit. - -Section discrete_measurable_bool. - -Definition discrete_measurable_bool : set (set bool) := [set: set bool]. - -Let discrete_measurable0 : discrete_measurable_bool set0. Proof. by []. Qed. - -Let discrete_measurableC X : - discrete_measurable_bool X -> discrete_measurable_bool (~` X). +Lemma discrete_measurableU (F : (set T)^nat) : + (forall i, discrete_measurable (F i)) -> + discrete_measurable (\bigcup_i F i). Proof. by []. Qed. -Let discrete_measurableU (F : (set bool)^nat) : - (forall i, discrete_measurable_bool (F i)) -> - discrete_measurable_bool (\bigcup_i F i). -Proof. by []. Qed. +End discrete_measurable. -HB.instance Definition _ := @isMeasurable.Build default_measure_display bool - discrete_measurable_bool discrete_measurable0 +HB.instance Definition _ := @isMeasurable.Build default_measure_display + unit discrete_measurable discrete_measurable0 discrete_measurableC discrete_measurableU. -End discrete_measurable_bool. - -Section discrete_measurable_nat. - -Definition discrete_measurable_nat : set (set nat) := [set: set nat]. - -Let discrete_measurable_nat0 : discrete_measurable_nat set0. Proof. by []. Qed. - -Let discrete_measurable_natC X : - discrete_measurable_nat X -> discrete_measurable_nat (~` X). -Proof. by []. Qed. - -Let discrete_measurable_natU (F : (set nat)^nat) : - (forall i, discrete_measurable_nat (F i)) -> - discrete_measurable_nat (\bigcup_i F i). -Proof. by []. Qed. - -HB.instance Definition _ := isMeasurable.Build default_measure_display nat - discrete_measurable_nat0 discrete_measurable_natC discrete_measurable_natU. +HB.instance Definition _ := @isMeasurable.Build default_measure_display + bool discrete_measurable discrete_measurable0 + discrete_measurableC discrete_measurableU. -End discrete_measurable_nat. +HB.instance Definition _ := @isMeasurable.Build default_measure_display + nat discrete_measurable discrete_measurable0 + discrete_measurableC discrete_measurableU. Definition sigma_display {T} : set (set T) -> measure_display. Proof. exact. Qed.