Slug #191
Slow lex gbasis
Description
The following example comes from an exercise I gave during Algebra Computazionale
Use QQ[a,b,x,y,z], Lex; I := Ideal(x-a^3-b^3-3, y-a^5-b^5-5, z-a^7-b^7-7); t0 := CpuTime(); RGB := ReducedGBasis(I); PrintLn "Tempo impiegato per calcolare RGB: ", DecimalStr(CpuTime()-t0);
On my computer, with the latest development version of CoCoA-5 and CoCoALib, the time taken is about 850s. On a student's computer (MS Windows, I believe), using the version of CoCoA-5 which was available 1-2 months ago on the website, the same computation takes about 60s.
I am mentioning this because I think we have not recently changed anything in the G-basis computation code...
I've put this in CoCoALib because I believe that's where the problem lies (even though it came to light when using CoCoA-5).
Related issues
History
#1 Updated by Anna Maria Bigatti almost 12 years ago
- Status changed from New to In Progress
John Abbott wrote:
The following example comes from an exercise I gave during Algebra Computazionale
[...]
On my computer, with the latest development version of CoCoA-5 and CoCoALib, the time taken is about 850s. On a student's computer (MS Windows, I believe), using the version of CoCoA-5 which was available 1-2 months ago on the website, the same computation takes about 60s.
Also my current version takes about 60s.
I guess you have some experimental part in your working version....
I think I really should add some extra info to VersionInfo ;-)
#2 Updated by John Abbott almost 12 years ago
- Status changed from In Progress to Closed
- % Done changed from 0 to 100
I did make veryclean
; sync with CVS, and make
.
Now mine takes about a minute too... very odd!
No idea why it was so slow before :-(
#3 Updated by Anna Maria Bigatti almost 12 years ago
John Abbott wrote:
No idea why it was so slow before :-(
I had a similar problem to what you described yesteray: old cocoa running while compiling the new one. Maybe the old one is not deleted until it is linking time.
#4 Updated by Anna Maria Bigatti over 11 years ago
- Project changed from CoCoA to CoCoALib
#5 Updated by Anna Maria Bigatti over 11 years ago
- Category set to Various
#6 Updated by Anna Maria Bigatti over 11 years ago
- Project changed from CoCoALib to CoCoA-5
- Category deleted (
Various)
#7 Updated by Anna Maria Bigatti over 11 years ago
- Target version set to CoCoA-5.0.3
#8 Updated by Anna Maria Bigatti almost 11 years ago
- Category set to Portability
- Assignee set to John Abbott