Slug #120
LT over QQ: surprisingly slow
Description
The following should compute a LT ideal of a small ideal (using lex).
It takes longer than I would expect over QQ -- it is quite fast over ZZ/(p), and produces ideal(x,y,z^10)
.
Over QQ it is really too slow (>20mins on my current computer)... JAA thinks there may really be a bug.
ring QQ = RingQQ(); PolyRing P = NewPolyRing(QQ, symbols("x","y","z"), lex); RingElem x = indet(P,0); RingElem y = indet(P,1); RingElem z = indet(P,2); RingElem g1 = x*x*x +x*x*z +x*z; RingElem g2 = x*x*x +x*y*y +1; RingElem g3 = x*x +x*y*z +y*y*y; ideal I(g1,g2,g3); cout << "LT(I)=" << LT(I) << endl;
Estimated time is only for locating the problem; it will have to be updated when the root cause is discovered.
Related issues
History
#1 Updated by John Abbott about 12 years ago
Here is another suspect starting ideal in QQ[x,y,z],Lex
[x^4 +x*y^2*z +y^4, x^3*y +x^2*z^2 +z^2]
#2 Updated by John Abbott about 12 years ago
My "noddy" program for computing GBases can do the whole computation in a few seconds...
#3 Updated by Anna Maria Bigatti over 11 years ago
- Tracker changed from Bug to Slug
- Subject changed from Surprisingly slow to LT over QQ: surprisingly slow
#4 Updated by Anna Maria Bigatti about 10 years ago
- Target version set to CoCoALib-0.99533 Easter14
#5 Updated by Anna Maria Bigatti about 10 years ago
- Category set to Various
#6 Updated by John Abbott about 10 years ago
- Target version changed from CoCoALib-0.99533 Easter14 to CoCoALib-0.99534 Seoul14
#7 Updated by John Abbott almost 10 years ago
- Target version changed from CoCoALib-0.99534 Seoul14 to CoCoALib-1.0
#8 Updated by John Abbott almost 8 years ago
- Related to Design #871: Redesign ideals added