Commit 2024-02-21 16:46 f17e2324

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refactor(MeasureTheory): redefine on measures (#10714) 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

Estimated changes