On Wednesday, October 29, 2014 7:14:43 AM UTC-7, Harald Schilly wrote: > > > > On Wednesday, October 29, 2014 1:25:08 PM UTC+1, parisse wrote: >> >> Just curious: what is the algorithm used by sage here? >> I have tried Bareiss, modular and p-adic with giac, and Bareiss seems the >> fastest: 0.02s on my Mac, vs about 1s for (proven) modular/p-adic. >> sage 6.3 returns the answer in 0.12s on my computer, while Maxima takes >> 15s. >> > Interesting. On my computer, determinant(mm) takes 13.9 seconds in Maxima. If I set ratmx:true, the time is 0. 25 seconds. Doing the computation in bigfloats takes 10 seconds.
Actually I would not expect ginormous integer determinants to be especially efficient; major effort has been expended in Maxima programming for determinants of matrices that are sparse with polynomial or rational function entries. I do not know that any modular methods have been put in there. > Sage uses different algorithms based on difficulty. > > http://git.sagemath.org/sage.git/tree/src/sage/matrix/matrix_integer_dense.pyx#n3252 > > I'm guessing in this case it's this branch: > > http://git.sagemath.org/sage.git/tree/src/sage/matrix/matrix_integer_dense_hnf.py#n184 > > -- harald > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
