Hello everyone, Please allow me to advertise a couple of tickets currently waiting to be reviewed that deal with fraction field elements, and in particular rational fractions in several variables:
https://trac.sagemath.org/ticket/25290 https://trac.sagemath.org/ticket/23909 https://trac.sagemath.org/ticket/16268 https://trac.sagemath.org/ticket/25318 (The patchbot appears to be broken right now, but with all four branches at once and no optional package installed, make ptestlong passes.) At least for some applications I'm interested in, these tickets bring Sage fraction field elements from "so slow they are unusable" to "not really great yet but reasonable". For example, this is with sage 8.3.beta5: sage: P.<x> = QQ[] ....: Q.<y> = Frac(P)[] ....: mat = matrix(3, 3, lambda i, j: (x+i*y+1)^j/(j*x*y+i)^(i+j)) ....: %time mat.det() CPU times: user 9.23 s, sys: 0 ns, total: 9.23 s Wall time: 9.23 s and this is what happens with all four branches merged in: sage: P.<x> = QQ[] ....: Q.<y> = Frac(P)[] ....: mat = matrix(3, 3, lambda i, j: (x+i*y+1)^j/(j*x*y+i)^(i+j)) ....: %time mat.det() CPU times: user 38.6 ms, sys: 238 µs, total: 38.9 ms Wall time: 37.2 ms (This example turned out to be a bit extreme, although I didn't choose it on purpose. But I'm observing speedups of ×5 to ×10 on real applications involving operations with rational fractions.) -- Marc -- 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 https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
