Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

[Merged by Bors] - feat(topology/algebra/ordered/basic): sequences tending to Inf/Sup #8524

Closed
wants to merge 2 commits into from

Conversation

sgouezel
Copy link
Collaborator

@sgouezel sgouezel commented Aug 3, 2021

We show that there exist monotone sequences tending to the Inf/Sup of a set in a conditionally complete linear order, as well as several related lemmas expressed in terms of is_lub and is_glb.


This is a common generalization of lemmas that showed up both in #8388 and #8266

@sgouezel sgouezel added the awaiting-review The author would like community review of the PR label Aug 3, 2021
@gebner gebner changed the title feat (topology/algebra/ordered/basic): sequences tending to Inf/Sup feat(topology/algebra/ordered/basic): sequences tending to Inf/Sup Aug 3, 2021
Copy link
Member

@PatrickMassot PatrickMassot left a comment

Choose a reason for hiding this comment

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

Thanks! It's a bit embarrassing that we had a version of this in the tutorials but not in mathlib. I wasn't even able to find the easy directions (if x is an upper bound of s and there is a sequence in s convering to x then is_lub s x). Do you mind adding this while you have the relevant minimal assumptions in mind?

src/order/basic.lean Outdated Show resolved Hide resolved
src/topology/algebra/ordered/basic.lean Outdated Show resolved Hide resolved
src/topology/algebra/ordered/basic.lean Outdated Show resolved Hide resolved
@PatrickMassot PatrickMassot 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 Aug 3, 2021
@sgouezel
Copy link
Collaborator Author

sgouezel commented Aug 3, 2021

I have added the fact that, if an upper bound belongs to the closure, then it is a lub, and taken all your comments into account (and moved everything to a better place in the file).

@sgouezel sgouezel 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 Aug 3, 2021
@PatrickMassot
Copy link
Member

bors merge

@github-actions github-actions bot added ready-to-merge All that is left is for bors to build and merge this PR. (Remember you need to say `bors r+`.) and removed awaiting-review The author would like community review of the PR labels Aug 3, 2021
bors bot pushed a commit that referenced this pull request Aug 3, 2021
…8524)

We show that there exist monotone sequences tending to the Inf/Sup of a set in a conditionally complete linear order, as well as several related lemmas expressed in terms of `is_lub` and `is_glb`.
@bors
Copy link

bors bot commented Aug 3, 2021

Pull request successfully merged into master.

Build succeeded:

@bors bors bot changed the title feat(topology/algebra/ordered/basic): sequences tending to Inf/Sup [Merged by Bors] - feat(topology/algebra/ordered/basic): sequences tending to Inf/Sup Aug 3, 2021
@bors bors bot closed this Aug 3, 2021
@bors bors bot deleted the exists_seq_mono branch August 3, 2021 17:55
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
ready-to-merge All that is left is for bors to build and merge this PR. (Remember you need to say `bors r+`.)
Projects
None yet
Development

Successfully merging this pull request may close these issues.

None yet

2 participants