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[Merged by Bors] - feat(topology/algebra/ordered): monotone continuous function is homeomorphism, relative version #4043

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@hrmacbeth hrmacbeth commented Sep 4, 2020

A function f : α → β restricts to a homeomorphism (Ioo a b) → β, if it (1) is order-preserving within the interval; (2) is continuous_on the interval; (3) tends to positive infinity at the right endpoint; and (4) tends to negative infinity at the left endpoint. The orders α, β are required to be conditionally complete, and the order on α must also be dense.


This is a relative version of #3843. As explained in a docstring, it is only one of dozens of possible relative versions -- one can vary the type of interval in both the source and target. I provide this one as a proof of concept (building up the infrastructure for any of the others should be possible with this as a model), and because it is needed for a future PR of @benjamindavidson.

Zulip discussion of one of the lemmas

Blocked by #3991.

@hrmacbeth hrmacbeth added awaiting-review The author would like community review of the PR blocked-by-other-PR This PR depends on another PR which is still in the queue. A bot manages this label via PR comment. and removed awaiting-review The author would like community review of the PR labels Sep 4, 2020
@github-actions github-actions bot added the merge-conflict Please `git merge origin/master` then a bot will remove this label. label Sep 9, 2020
@github-actions github-actions bot removed the merge-conflict Please `git merge origin/master` then a bot will remove this label. label Sep 9, 2020
@robertylewis robertylewis changed the title feat(topology/algebra/ordered): monotone continuous function is homeomorphism, relative version (dep #3991) feat(topology/algebra/ordered): monotone continuous function is homeomorphism, relative version Sep 9, 2020
@robertylewis robertylewis added awaiting-review The author would like community review of the PR and removed blocked-by-other-PR This PR depends on another PR which is still in the queue. A bot manages this label via PR comment. labels Sep 9, 2020
@robertylewis robertylewis added awaiting-author A reviewer has asked the author a question or requested changes and removed awaiting-review The author would like community review of the PR labels Sep 11, 2020
@hrmacbeth hrmacbeth added awaiting-review The author would like community review of the PR and removed awaiting-author A reviewer has asked the author a question or requested changes labels Sep 11, 2020
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bors d+

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bors bot commented Sep 14, 2020

✌️ hrmacbeth can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

@robertylewis robertylewis added delegated The PR author may merge after reviewing final suggestions. and removed awaiting-review The author would like community review of the PR labels Sep 14, 2020
hrmacbeth and others added 2 commits September 14, 2020 16:58
Co-authored-by: sgouezel <sebastien.gouezel@univ-rennes1.fr>
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bors r+

bors bot pushed a commit that referenced this pull request Sep 14, 2020
…morphism, relative version (#4043)

A function `f : α → β` restricts to a homeomorphism `(Ioo a b) → β`, if it (1) is order-preserving within the interval; (2) is `continuous_on` the interval; (3) tends to positive infinity at the right endpoint; and (4) tends to negative infinity at the left endpoint. The orders `α`, `β` are required to be conditionally complete, and the order on `α` must also be dense.
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bors bot commented Sep 15, 2020

Pull request successfully merged into master.

Build succeeded:

@bors bors bot changed the title feat(topology/algebra/ordered): monotone continuous function is homeomorphism, relative version [Merged by Bors] - feat(topology/algebra/ordered): monotone continuous function is homeomorphism, relative version Sep 15, 2020
@bors bors bot closed this Sep 15, 2020
@bors bors bot deleted the strict-mono-on-homeomorph branch September 15, 2020 01:03
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