Skip to content

[Merged by Bors] - refactor(MeasureTheory): redefine on measures#10714

Closed
urkud wants to merge 1 commit intomasterfrom
YK-meas-le
Closed

[Merged by Bors] - refactor(MeasureTheory): redefine on measures#10714
urkud wants to merge 1 commit intomasterfrom
YK-meas-le

Conversation

@urkud
Copy link
Copy Markdown
Member

@urkud urkud commented Feb 19, 2024

Redefine on MeasureTheory.Measure
so that μ ≤ ν ↔ ∀ s, μ s ≤ ν s by definition
instead of ∀ s, MeasurableSet s → μ s ≤ ν s.

Reasons

  • this way it is defeq to on outer measures;
  • if we decide to introduce an order on all DFunLike types
    and migrate measures to FunLike, then this is unavoidable;
  • the reasoning for the old definition was
    "it's slightly easier to prove μ ≤ ν this way";
    the counter-argument is
    "it's slightly harder to apply μ ≤ ν this way".

Other changes

  • golf some proofs broken by this change;
  • add @[gcongr] tags to some ENNReal lemmas;
  • fix the name
    ENNReal.coe_lt_coe_of_le -> ENNReal.ENNReal.coe_lt_coe_of_lt;
  • drop an unneeded MeasurableSet assumption
    in set_lintegral_pdf_le_map

Open in Gitpod

Redefine `≤` on `MeasureTheory.Measure`
so that `μ ≤ ν ↔ ∀ s, μ s ≤ ν s` by definition
instead of `∀ s, MeasurableSet s → μ s ≤ ν s`.

The reasons are:

- this way it is defeq to `≤` on outer measures;
- if we decide to introduce an order on all `DFunLike` types
  **and** migrate measures to `FunLike`, then this is unavoidable;
- the reasoning for the old definition was
  "it's slightly easier to prove `μ ≤ ν` this way";
  the counter-argument is
  "it's slightly harder to apply `μ ≤ ν` this way".

Other changes

- golf some proofs broken by this change;
- add `@[gcongr]` tags to some `ENNReal` lemmas;
- fix the name
  `ENNReal.coe_lt_coe_of_le` -> `ENNReal.ENNReal.coe_lt_coe_of_lt`;
- drop an unneeded `MeasurableSet` assumption
  in `set_lintegral_pdf_le_map`
@urkud urkud added awaiting-review t-measure-probability Measure theory / Probability theory labels Feb 19, 2024
Copy link
Copy Markdown
Member

@fpvandoorn fpvandoorn left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

LGTM

Thanks!

bors merge

#align ennreal.to_real_le_to_real ENNReal.toReal_le_toReal

@[gcongr]
theorem toReal_mono (hb : b ≠ ∞) (h : a ≤ b) : a.toReal ≤ b.toReal :=
Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

unrelated to this PR: we should move finiteness to mathlib and add it as a gcongr discharger.

@ghost ghost added ready-to-merge This PR has been sent to bors. and removed awaiting-review labels Feb 21, 2024
mathlib-bors bot pushed a commit that referenced this pull request Feb 21, 2024
Redefine `≤` on `MeasureTheory.Measure`
so that `μ ≤ ν ↔ ∀ s, μ s ≤ ν s` by definition
instead of `∀ s, MeasurableSet s → μ s ≤ ν s`.

### Reasons

- this way it is defeq to `≤` on outer measures;
- if we decide to introduce an order on all `DFunLike` types
  **and** migrate measures to `FunLike`, then this is unavoidable;
- the reasoning for the old definition was
  "it's slightly easier to prove `μ ≤ ν` this way";
  the counter-argument is
  "it's slightly harder to apply `μ ≤ ν` this way".

### Other changes

- golf some proofs broken by this change;
- add `@[gcongr]` tags to some `ENNReal` lemmas;
- fix the name
  `ENNReal.coe_lt_coe_of_le` -> `ENNReal.ENNReal.coe_lt_coe_of_lt`;
- drop an unneeded `MeasurableSet` assumption
  in `set_lintegral_pdf_le_map`
@mathlib-bors
Copy link
Copy Markdown
Contributor

mathlib-bors bot commented Feb 21, 2024

This PR was included in a batch that was canceled, it will be automatically retried

mathlib-bors bot pushed a commit that referenced this pull request Feb 21, 2024
Redefine `≤` on `MeasureTheory.Measure`
so that `μ ≤ ν ↔ ∀ s, μ s ≤ ν s` by definition
instead of `∀ s, MeasurableSet s → μ s ≤ ν s`.

### Reasons

- this way it is defeq to `≤` on outer measures;
- if we decide to introduce an order on all `DFunLike` types
  **and** migrate measures to `FunLike`, then this is unavoidable;
- the reasoning for the old definition was
  "it's slightly easier to prove `μ ≤ ν` this way";
  the counter-argument is
  "it's slightly harder to apply `μ ≤ ν` this way".

### Other changes

- golf some proofs broken by this change;
- add `@[gcongr]` tags to some `ENNReal` lemmas;
- fix the name
  `ENNReal.coe_lt_coe_of_le` -> `ENNReal.ENNReal.coe_lt_coe_of_lt`;
- drop an unneeded `MeasurableSet` assumption
  in `set_lintegral_pdf_le_map`
@mathlib-bors
Copy link
Copy Markdown
Contributor

mathlib-bors bot commented Feb 21, 2024

Pull request successfully merged into master.

Build succeeded:

@mathlib-bors mathlib-bors bot changed the title refactor(MeasureTheory): redefine on measures [Merged by Bors] - refactor(MeasureTheory): redefine on measures Feb 21, 2024
@mathlib-bors mathlib-bors bot closed this Feb 21, 2024
@mathlib-bors mathlib-bors bot deleted the YK-meas-le branch February 21, 2024 17:43
thorimur pushed a commit that referenced this pull request Feb 24, 2024
Redefine `≤` on `MeasureTheory.Measure`
so that `μ ≤ ν ↔ ∀ s, μ s ≤ ν s` by definition
instead of `∀ s, MeasurableSet s → μ s ≤ ν s`.

### Reasons

- this way it is defeq to `≤` on outer measures;
- if we decide to introduce an order on all `DFunLike` types
  **and** migrate measures to `FunLike`, then this is unavoidable;
- the reasoning for the old definition was
  "it's slightly easier to prove `μ ≤ ν` this way";
  the counter-argument is
  "it's slightly harder to apply `μ ≤ ν` this way".

### Other changes

- golf some proofs broken by this change;
- add `@[gcongr]` tags to some `ENNReal` lemmas;
- fix the name
  `ENNReal.coe_lt_coe_of_le` -> `ENNReal.ENNReal.coe_lt_coe_of_lt`;
- drop an unneeded `MeasurableSet` assumption
  in `set_lintegral_pdf_le_map`
thorimur pushed a commit that referenced this pull request Feb 26, 2024
Redefine `≤` on `MeasureTheory.Measure`
so that `μ ≤ ν ↔ ∀ s, μ s ≤ ν s` by definition
instead of `∀ s, MeasurableSet s → μ s ≤ ν s`.

### Reasons

- this way it is defeq to `≤` on outer measures;
- if we decide to introduce an order on all `DFunLike` types
  **and** migrate measures to `FunLike`, then this is unavoidable;
- the reasoning for the old definition was
  "it's slightly easier to prove `μ ≤ ν` this way";
  the counter-argument is
  "it's slightly harder to apply `μ ≤ ν` this way".

### Other changes

- golf some proofs broken by this change;
- add `@[gcongr]` tags to some `ENNReal` lemmas;
- fix the name
  `ENNReal.coe_lt_coe_of_le` -> `ENNReal.ENNReal.coe_lt_coe_of_lt`;
- drop an unneeded `MeasurableSet` assumption
  in `set_lintegral_pdf_le_map`
riccardobrasca pushed a commit that referenced this pull request Mar 1, 2024
Redefine `≤` on `MeasureTheory.Measure`
so that `μ ≤ ν ↔ ∀ s, μ s ≤ ν s` by definition
instead of `∀ s, MeasurableSet s → μ s ≤ ν s`.

### Reasons

- this way it is defeq to `≤` on outer measures;
- if we decide to introduce an order on all `DFunLike` types
  **and** migrate measures to `FunLike`, then this is unavoidable;
- the reasoning for the old definition was
  "it's slightly easier to prove `μ ≤ ν` this way";
  the counter-argument is
  "it's slightly harder to apply `μ ≤ ν` this way".

### Other changes

- golf some proofs broken by this change;
- add `@[gcongr]` tags to some `ENNReal` lemmas;
- fix the name
  `ENNReal.coe_lt_coe_of_le` -> `ENNReal.ENNReal.coe_lt_coe_of_lt`;
- drop an unneeded `MeasurableSet` assumption
  in `set_lintegral_pdf_le_map`
dagurtomas pushed a commit that referenced this pull request Mar 22, 2024
Redefine `≤` on `MeasureTheory.Measure`
so that `μ ≤ ν ↔ ∀ s, μ s ≤ ν s` by definition
instead of `∀ s, MeasurableSet s → μ s ≤ ν s`.

### Reasons

- this way it is defeq to `≤` on outer measures;
- if we decide to introduce an order on all `DFunLike` types
  **and** migrate measures to `FunLike`, then this is unavoidable;
- the reasoning for the old definition was
  "it's slightly easier to prove `μ ≤ ν` this way";
  the counter-argument is
  "it's slightly harder to apply `μ ≤ ν` this way".

### Other changes

- golf some proofs broken by this change;
- add `@[gcongr]` tags to some `ENNReal` lemmas;
- fix the name
  `ENNReal.coe_lt_coe_of_le` -> `ENNReal.ENNReal.coe_lt_coe_of_lt`;
- drop an unneeded `MeasurableSet` assumption
  in `set_lintegral_pdf_le_map`
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

ready-to-merge This PR has been sent to bors. t-measure-probability Measure theory / Probability theory

Projects

None yet

Development

Successfully merging this pull request may close these issues.

2 participants