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[Merged by Bors] - feat(topology/algebra/order/compact): Sup is continuous #13347
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Other than a few minor comments this looks good to me.
/-- A continuous function is bounded below on a compact set. -/ | ||
lemma is_compact.bdd_below_image {α : Type u} [topological_space α] [linear_order α] |
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I understand why you put these here, but I think they might be better with the other things related to the extreme value theorem in topology.algebra.order.compact
(for example, near is_compact.exists_forall_le
). Although this is not a strong preference.
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I can take a look what will break if is_compact.bdd_[below|above]
are moved to topology.algebra.order.compact
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In retrospect I think it's probably better to leave those lemmas where they are. They are related to the extreme value theorem, but much weaker, so I think it's fine to put them where they are.
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bors d+
✌️ fpvandoorn can now approve this pull request. To approve and merge a pull request, simply reply with |
Co-authored-by: Johan Commelin <johan@commelin.net>
bors merge |
* Prove that the `Sup` of a binary function over a compact set is continuous in the second variable * Some other lemmas about `Sup` * Move and generalize `is_compact.bdd_[above|below]_image` * from the sphere eversion project
Pull request successfully merged into master. Build succeeded: |
Sup
of a binary function over a compact set is continuous in the second variableSup
is_compact.bdd_[above|below]_image