> That said, I am wondering if this is perhaps a bug in the default > implementation of determinant()? > It seems strange to me that it takes 8 minutes to compute a determinant of a > 34x34 matrix while other algorithms do it within a second.
Yeah, it looks like pari's Gauss-Bareiss takes forever on this matrix, even though its classical Gaussian is quick: sage: time m2._det_pari(1) 336140000000000000 Time: CPU 0.00 s, Wall: 0.00 s sage: time m2._det_pari(0) 336140000000000000 Time: CPU 597.13 s, Wall: 597.10 s Kind of funny: _det_pari(0) is so slow on this particular matrix that it's five orders of magnitude faster to square m2 and take the root of the determinant! sage: %timeit (m2)._det_pari(1) 125 loops, best of 3: 3.39 ms per loop sage: %timeit (m2*m2)._det_pari(0)^(1/2) 125 loops, best of 3: 5.92 ms per loop Doug -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To post to this group, send email to sage-devel@googlegroups.com. To unsubscribe from this group, send email to sage-devel+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel?hl=en.
