refactor(topology,calculus): change subset condition for composition #1549
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robertylewis
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Thanks a lot for your comments @PatrickMassot. I think I have addressed them all. |
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…eanprover-community#1549) * refactor(topology,calculus): change subset condition for composition * improve docstrings * add is_open Ioi * reviewer's comments * typo
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A grab bag of small additions that I need in further developments. I don't really think it makes sense to split it into several smaller PRs, but if you insist I will.
The main change is the reformulation of the subset condition for composition. For instance, for
continuous_on, the condition for continuity of the composition off(continuous ons) andg(continuous ont) wasf '' s ⊆ t. I change it everywhere tos ⊆ f ⁻¹' t, which is equivalent but computes a lot better (belonging to the image is something complicated, with an existential quantifier, while belonging to the preimage is much simpler). This opened the way to much better simp automation for manifolds.