Le vendredi 11 novembre 2016 07:03:46 UTC+1, Bill Hart a écrit : > > I assume you are using the modular algorithm to remove the final lot of > content at the end of the psr algorithm. Otherwise the algorithm takes > quite a long time, since even if we remove the known factors of the content > along the way, as specified by the algorithm, the result is far from > primitive, and so computing the content in the final step of the algorithm > takes a long time. > > Bill. >
I'm using a trick for the last step of psrgcd: since the gcd should be of degree 6 wrt y (obtained by evaluation of other variables), when I have the remainder of degree 6 (1276 monomials), I check that the division from the previous remainder (102 monomials) with the primitive part of this remainder is exact, this saves one pseudo-division. Looking how the content (188 monomials) is computed, it's done by exact divisions only (it's the leading coefficient up to trivial coefficients). -- 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.
