Opened 12 years ago
Closed 12 years ago
#1617 closed defect (fixed)
[with patch, positive review] speed problem when factoring polynoms
Reported by: | schilly | Owned by: | was |
---|---|---|---|
Priority: | major | Milestone: | sage-2.10.1 |
Component: | commutative algebra | Keywords: | |
Cc: | Merged in: | ||
Authors: | Reviewers: | ||
Report Upstream: | Work issues: | ||
Branch: | Commit: | ||
Dependencies: | Stopgaps: |
Description
There is a huge speed difference. Any special reasons? A novice user would possibly not understand why!
var('x,y') time p1=factor(x^99+y^99) Time: CPU 0.05 s, Wall: 58.43 s
R.<x,y> = QQ[] time p2=factor(x^99+y^99) Time: CPU 0.06 s, Wall: 0.06 s
Attachments (1)
Change History (10)
comment:1 Changed 12 years ago by
- Component changed from algebraic geometry to commutative algebra
- Milestone set to sage-2.9.2
- Owner changed from was to malb
comment:2 Changed 12 years ago by
- Summary changed from speed problem when factoring polynoms to [wontfix?] speed problem when factoring polynoms
I vote for wontfix
because I see no way of fixing this, this is a Maxima speed issue. The only fix I could think of is to add something about this in some documentation.
comment:3 Changed 12 years ago by
- Owner changed from malb to was
- Status changed from new to assigned
Changed 12 years ago by
comment:4 Changed 12 years ago by
- Summary changed from [wontfix?] speed problem when factoring polynoms to [with patch, needs review] speed problem when factoring polynoms
comment:5 Changed 12 years ago by
At least one comment is wrong in the patch since the "-" no longer shows up:
2288 2288 Notice that the -1 factor is separated out: 2289 2289 sage: f.factor_list() 2290 [(-1, 1), (y - x, 1), (y^2 + x*y + x^2, 1)] 2290 [(x - y, 1), (y^2 + x*y + x^2, 1)]
Cheers,
Michael
comment:6 Changed 12 years ago by
- Summary changed from [with patch, needs review] speed problem when factoring polynoms to [with patch, needs review after #1391 is applied] speed problem when factoring polynoms
This patch could interact with #1391 (http://trac.sagemath.org/sage_trac/ticket/1391). That one should be applied first, I think, and then this looked at again.
comment:7 Changed 12 years ago by
- Summary changed from [with patch, needs review after #1391 is applied] speed problem when factoring polynoms to [with patch, positive review] speed problem when factoring polynoms
The patch applies to 2.10.1.alpha1 (hunks, but success). Afterwards, only the toy_buchberger.py
tests fail which is unrelated. Thus, I say: apply.
comment:8 Changed 12 years ago by
The mabshoff comment above about "At least one comment is wrong in the patch since the "-" no longer shows up" was caused by ncalexan's patch related to factorization.py, which was after #1617.
comment:9 Changed 12 years ago by
- Resolution set to fixed
- Status changed from assigned to closed
Merged in Sage 2.10.1.alpha2
This is likely caused by using Maxima's factoring vs. Singular's libfactor. In the first case x and y are symbolic.
Cheers,
Michael