Opened 9 years ago
Closed 9 years ago
#12528 closed enhancement (fixed)
Little optimizations in CombinatorialFreeModule
Reported by: | nthiery | Owned by: | jason, was |
---|---|---|---|
Priority: | major | Milestone: | sage-5.0 |
Component: | linear algebra | Keywords: | |
Cc: | sage-combinat, jhpalmieri | Merged in: | sage-5.0.beta6 |
Authors: | Nicolas M. Thiéry | Reviewers: | Florent Hivert, John Palmieri |
Report Upstream: | N/A | Work issues: | |
Branch: | Commit: | ||
Dependencies: | #12484 | Stopgaps: |
Description (last modified by )
With the attached optimizations, the following typical calculation from Andrew Matthas goes twice faster (it involves a lot of arithmetic on module elements with very few terms)::
sage: W = SymmetricGroup(4) sage: W.cartan_type = lambda: CartanType("A3") sage: R=FractionField(PolynomialRing(ZZ,'x')); x=R.gen() sage: H=IwahoriHeckeAlgebraT(W,x,base_ring = R) sage: L=[H.one()]; # define Jucys-Murphy elements sage: for k in xrange(1,4): L.append(H._q1**-1*H.algebra_generators()[k]*L[k-1]*H.algebra_generators()[k]) sage: content=[0,1,-1,0] # content vector for Tableau([[1,2],[3,4]]) sage: %time prod( (L[k]-x**c)/(x**content[k]-x**c) for k in xrange(len(content)) for c in xrange(-k,k+1) if c<>content[k]) CPU times: user 2.26 s, sys: 0.00 s, total: 2.27 s Wall time: 2.27 s
Was 4.5s before the patch.
The patch also involve two changes in the Iwahori Hecke Algebra code to use better primitives of CombinatorialFreeModule?.
(trivial syntactical dependency upon #12484)
Attachments (1)
Change History (9)
comment:1 Changed 9 years ago by
- Status changed from new to needs_review
comment:2 Changed 9 years ago by
- Dependencies set to #12484
- Description modified (diff)
comment:3 follow-up: ↓ 4 Changed 9 years ago by
- Cc jhpalmieri added
- Reviewers set to Florent Hivert, John Palmieri
comment:4 in reply to: ↑ 3 ; follow-up: ↓ 5 Changed 9 years ago by
Replying to nthiery:
All test pass. I let Florent put the final positive review once John will have given his green light.
While we are waiting for John, can you add a proper commit message ? Jeroen will ask you to do so anyway...
Changed 9 years ago by
comment:5 in reply to: ↑ 4 Changed 9 years ago by
Replying to hivert:
While we are waiting for John, can you add a proper commit message ? Jeroen will ask you to do so anyway...
Shoot, I was sure I had done it. Well, now its done :-)
comment:6 follow-up: ↓ 7 Changed 9 years ago by
The Steenrod algebra change looks fine to me.
comment:7 in reply to: ↑ 6 Changed 9 years ago by
- Status changed from needs_review to positive_review
comment:8 Changed 9 years ago by
- Merged in set to sage-5.0.beta6
- Resolution set to fixed
- Status changed from positive_review to closed
The new patch fixes a (trivial?) doctest failure in sage.algebra/steenrod_algebra/steenrod_algebra.py (John, please double check it!), and includes further review improvements from Florent.
All test pass. I let Florent put the final positive review once John will have given his green light.