graphs: make init_short_digraph always sort neighbors but without the extra log complexity (2nd try) #38664
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
dcoudert
approved these changes
Sep 17, 2024
vbraun
pushed a commit
to vbraun/sage
that referenced
this pull request
Sep 19, 2024
…rs but without the extra log complexity (2nd try)
<!-- ^ Please provide a concise and informative title. -->
<!-- ^ Don't put issue numbers in the title, do this in the PR
description below. -->
<!-- ^ For example, instead of "Fixes sagemath#12345" use "Introduce new method
to calculate 1 + 2". -->
<!-- v Describe your changes below in detail. -->
<!-- v Why is this change required? What problem does it solve? -->
<!-- v If this PR resolves an open issue, please link to it here. For
example, "Fixes sagemath#12345". -->
This PR is based on the closed PR sagemath#38427 (by myself) that was breaking
too much doctests.
This PR improve the `init_short_digraph` function that is used to
initialize `StaticSparseCGraph` (used for immutable `Graph` and
`DiGraph`).
Before, a boolean parameter `sort_neighbors` was used to specify if we
wanted to sort the neighbors or not. It implied an extra `log` in the
complexity (as `qsort` was called).
With this PR, the neighbors are always sorted at no extra cost. It is
done by appending to the neighbors list the vertices in the correct
order so the call to `qsort` is not needed anymore.
This PR partly reverts sagemath#38198 and mostly reverts sagemath#37662
Contrary to PR sagemath#38427, I did not include the patch that remove the
sorting of vertices when StaticSparseGraph are initialized because it
was breaking too many doctests. Instead I added a option to disabled
said sorting and use it in my doctests to check that the new code works.
### 📝 Checklist
<!-- Put an `x` in all the boxes that apply. -->
- [x] The title is concise and informative.
- [x] The description explains in detail what this PR is about.
- [ ] I have linked a relevant issue or discussion.
- [x] I have created tests covering the changes.
- [ ] I have updated the documentation and checked the documentation
preview.
### ⌛ Dependencies
<!-- List all open PRs that this PR logically depends on. For example,
-->
<!-- - sagemath#12345: short description why this is a dependency -->
<!-- - sagemath#34567: ... -->
URL: sagemath#38664
Reported by: cyrilbouvier
Reviewer(s): David Coudert
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This PR is based on the closed PR #38427 (by myself) that was breaking too much doctests.
This PR improve the
init_short_digraphfunction that is used to initializeStaticSparseCGraph(used for immutableGraphandDiGraph).Before, a boolean parameter
sort_neighborswas used to specify if we wanted to sort the neighbors or not. It implied an extralogin the complexity (asqsortwas called).With this PR, the neighbors are always sorted at no extra cost. It is done by appending to the neighbors list the vertices in the correct order so the call to
qsortis not needed anymore.This PR partly reverts #38198 and mostly reverts #37662
Contrary to PR #38427, I did not include the patch that remove the sorting of vertices when StaticSparseGraph are initialized because it was breaking too many doctests. Instead I added a option to disabled said sorting and use it in my doctests to check that the new code works.
📝 Checklist
⌛ Dependencies