diff --git a/CHANGELOG_UNRELEASED.md b/CHANGELOG_UNRELEASED.md index 9fee1fd696..1809a6f273 100644 --- a/CHANGELOG_UNRELEASED.md +++ b/CHANGELOG_UNRELEASED.md @@ -97,6 +97,9 @@ + module `gauss_integral_proof` + lemma `integral0y_gauss` +- in `normedtype.v`: + + lemmas `ninfty`, `cvgy_compNP` + ### Changed - in `lebesgue_integral.v` @@ -120,6 +123,9 @@ - in file `separation_axioms.v`, updated `discrete_hausdorff`, and `discrete_zero_dimension` to take a `discreteTopologicalType`. +- in `normedtype.v`: + + lemma `cvgyNP` renamed to `cvgNy_compN` and generalized + ### Renamed - in `measure.v` diff --git a/theories/normedtype.v b/theories/normedtype.v index 686872e076..2968505c38 100644 --- a/theories/normedtype.v +++ b/theories/normedtype.v @@ -387,6 +387,14 @@ apply/seteqP; split => [A [M [Mreal MA]]|A [M [Mreal MA]]]. by exists (- M); rewrite ?realN; split=> // x; rewrite ltrNr => /MA. Qed. +Lemma ninfty {R : numFieldType} : (- x : R)%R @[x --> +oo] = -oo. +Proof. +apply/seteqP; split => [A [M [Mreal MA]]|A [M [Mreal MA]]]. + exists (- M); rewrite realN; split => // x. + by rewrite -ltrNr => /MA/=; rewrite opprK. +by exists (- M); rewrite ?realN; split=> // x; rewrite ltrNl => /MA. +Qed. + Section infty_nbhs_instances. Context {R : numFieldType}. Implicit Types r : R. @@ -1476,13 +1484,23 @@ Proof. by rewrite at_leftN -?fmap_comp; under [_ \o _]eq_fun => ? do rewrite /= opprK. Qed. -Lemma cvgyNP {T : topologicalType} {R : numFieldType} - (f : R -> T) (l : T) : +Lemma cvgNy_compNP {T : topologicalType} {R : numFieldType} (f : R -> T) + (l : set_system T) : f x @[x --> -oo] --> l <-> (f \o -%R) x @[x --> +oo] --> l. Proof. have f_opp : f =1 (fun x => (f \o -%R) (- x)) by move=> x; rewrite /comp opprK. by rewrite (eq_cvg -oo _ f_opp) fmap_comp ninftyN. Qed. +#[deprecated(since="mathcomp-analysis 1.9.0", note="renamed to `cvgNy_compNP`")] +Notation cvgyNP := cvgNy_compNP (only parsing). + +Lemma cvgy_compNP {T : topologicalType} {R : numFieldType} (f : R -> T) + (l : set_system T) : + f x @[x --> +oo] --> l <-> (f \o -%R) x @[x --> -oo] --> l. +Proof. +have f_opp : f =1 (fun x => (f \o -%R) (- x)) by move=> x; rewrite /comp opprK. +by rewrite (eq_cvg +oo _ f_opp) fmap_comp ninfty. +Qed. Section open_itv_subset. Context {R : realType}. diff --git a/theories/realfun.v b/theories/realfun.v index 865431d671..173402202e 100644 --- a/theories/realfun.v +++ b/theories/realfun.v @@ -333,7 +333,7 @@ Lemma cvg_ninftyP (f : R -> R) (l : R) : f x @[x --> -oo] --> l <-> forall u : R^nat, (u n @[n --> \oo] --> -oo) -> f (u n) @[n --> \oo] --> l. Proof. -rewrite cvgyNP cvg_pinftyP/= (@bij_forall R^nat _ -%R)//. +rewrite cvgNy_compNP cvg_pinftyP/= (@bij_forall R^nat _ -%R)//. have u_opp (u : R^nat) : ((- u) n @[n --> \oo] --> +oo) = (u n @[n --> \oo] --> -oo). by rewrite propeqE cvgNry.