Opened 2 years ago
Closed 2 years ago
#29894 closed enhancement (fixed)
add minimal interface for using ZZ[x]-matrices from flint
Reported by: | chapoton | Owned by: | |
---|---|---|---|
Priority: | major | Milestone: | sage-9.2 |
Component: | interfaces | Keywords: | |
Cc: | vdelecroix | Merged in: | |
Authors: | Frédéric Chapoton | Reviewers: | Travis Scrimshaw |
Report Upstream: | N/A | Work issues: | |
Branch: | 1f52255 (Commits, GitHub, GitLab) | Commit: | 1f52255c43134cf47840466f3ca27fc79bd4e346 |
Dependencies: | Stopgaps: |
Description
So that one may use this later to compute determinants in this case, for example.
Change History (8)
comment:1 Changed 2 years ago by
- Branch set to u/chapoton/29894
- Commit set to 1f52255c43134cf47840466f3ca27fc79bd4e346
- Status changed from new to needs_review
comment:2 Changed 2 years ago by
Could we add at least one little direct use for this interface, say in computing the determinants as mentioned in the ticket description?
comment:3 Changed 2 years ago by
ok, I will try to think about it. I had some use case, but it turned out to be slower than the existing method.
comment:4 Changed 2 years ago by
That is interesting and surprising to me. Bill probably would like to know about that. The flint version might also be asymptotically faster. Plus, I am generally a fan of having multiple implementations available and giving the choice to the user (if for nothing else other than testing).
comment:5 Changed 2 years ago by
My test case was (for M upper triangular square matrix with 1 on the diagonal)
det(x M^t + M)
versus
charpoly(-M (M^t)^(-1))
and the inversion + product + charpoly was much faster than the det.
comment:6 Changed 2 years ago by
maybe useful for Alexander polynomial from Seifert matrix, see #29952
comment:7 Changed 2 years ago by
- Reviewers set to Travis Scrimshaw
- Status changed from needs_review to positive_review
Perhaps that is just a special case of the fact it is a upper unitriangular matrix? Anyways, I am not going to fret over not having a definitive use case at this time. It doesn't hurt anything to have the interface all setup.
comment:8 Changed 2 years ago by
- Branch changed from u/chapoton/29894 to 1f52255c43134cf47840466f3ca27fc79bd4e346
- Resolution set to fixed
- Status changed from positive_review to closed
New commits:
introduce minimal interface for using ZZ[x] matrices in Flint