diff --git a/CHANGELOG_UNRELEASED.md b/CHANGELOG_UNRELEASED.md index ddff91f16c..5cfb7238f9 100644 --- a/CHANGELOG_UNRELEASED.md +++ b/CHANGELOG_UNRELEASED.md @@ -50,10 +50,10 @@ `disjoint_caratheodoryIU`, `caratheodory_additive`, `caratheodory_lim_lee`, `caratheodory_measurable_trivIset_bigcup`, `caratheodory_measurable_bigcup` - + definitions `measurable`, `caratheodory_mixin`, `caratheodory_measurableType` + + definitions `caratheodory_type`, `caratheodory_mixin`, `caratheodory_measurableType` + lemmas `caratheodory_measure0`, `caratheodory_measure_ge0`, `caratheodory_measure_sigma_additive`, - defintions `caratheodory_measure_mixin`, `measure_of_outer_measure`, + defintions `caratheodory_measure_mixin`, `caratheodory_measure`, lemma `caratheodory_measure_complete` ### Changed diff --git a/theories/measure.v b/theories/measure.v index fcc3fde32a..cd1ec7960e 100644 --- a/theories/measure.v +++ b/theories/measure.v @@ -37,14 +37,13 @@ From HB Require Import structures. (* i.e., forall Y, mu X = mu (X `&` Y) + mu (X `&` ~` Y) *) (* *) (* Caratheodory theorem: *) -(* caratheodory_measurableType mu == measurableType built from the outer *) -(* measure mu, formed by mu.-measurable sets *) -(* measure_of_outer_measure mu == the restriction of the outer measure mu to *) -(* the sigma algebra of Caratheodory measurable sets *) -(* is a measure *) -(* caratheodory_measure_complete == sets that are negligible for *) -(* measure_of_outer_measure are Caratheodory *) -(* measurable *) +(* caratheodory_type mu := T, where mu : {outer_measure set T -> {ereal R}} *) +(* it is a canonical mesurableType copy of T. *) +(* caratheodory_measure mu == the restriction of the outer measure mu to the *) +(* sigma algebra of Caratheodory measurable sets is a *) +(* measure *) +(* Remark: sets that are negligible for *) +(* caratheodory_measure are Caratheodory measurable *) (* *) (******************************************************************************) @@ -999,19 +998,20 @@ Qed. End caratheodory_theorem_sigma_algebra. -Definition measurables (R : realType) (T : Type) +Definition caratheodory_type (R : realType) (T : Type) (mu : {outer_measure set T -> {ereal R}}) := T. Section caratheodory_sigma_algebra. Variables (R : realType) (T : Type) (mu : {outer_measure set T -> {ereal R}}). -HB.instance Definition caratheodory_mixin := @isMeasurable.Build (measurables mu) - mu.-measurable - (caratheodory_measurable_set0 mu) - (@caratheodory_measurable_setC _ _ mu) - (@caratheodory_measurable_bigcup _ _ mu). +HB.instance Definition caratheodory_mixin := @isMeasurable.Build + (caratheodory_type mu) mu.-measurable + (caratheodory_measurable_set0 mu) + (@caratheodory_measurable_setC _ _ mu) + (@caratheodory_measurable_bigcup _ _ mu). -Definition caratheodory_measurableType := [the measurableType of measurables mu]. +Definition caratheodory_measurableType := + [the measurableType of caratheodory_type mu]. End caratheodory_sigma_algebra. Section caratheodory_measure. @@ -1047,11 +1047,11 @@ Qed. Definition caratheodory_measure_mixin := Measure.Axioms caratheodory_measure0 caratheodory_measure_ge0 caratheodory_measure_sigma_additive. -Definition measure_of_outer_measure : {measure set (measurables mu) -> _} := +Definition caratheodory_measure : {measure set (caratheodory_type mu) -> _} := Measure.Pack _ caratheodory_measure_mixin. Lemma caratheodory_measure_complete (B : set U) : - measure_of_outer_measure.-negligible B -> mu.-measurable B. + caratheodory_measure.-negligible B -> mu.-measurable B. Proof. move=> [A [mA muA0 BA]]; apply le_caratheodory_measurable => X. suff -> : mu (X `&` B) = 0%:E.