Indeed. Unfortunately, the patch file is rather large, which makes it difficult to have it tested and reviewed, and to keep it alive as other Sage code changes. A while ago I spoke to Martin Albrecht about this and we are both still interested in trying to push #4000 a little harder again very soon, but I did not have very much time in the last three weeks.
Sebastian On 29 Apr, 18:36, Robert Bradshaw <[email protected]> wrote: > On Apr 29, 2010, at 9:54 AM, Pierre wrote: > > > > > Dear all, > > > Not sure if this is for sage-devel or sage-support. Here's a > > 'benchmark' which I find stunning: > > > sage: A= MatrixSpace(QQ['t'], 8).random_element() > > sage: %time B= A*A > > CPU times: user 0.04 s, sys: 0.00 s, total: 0.04 s > > Wall time: 0.04 s > > > sage: C= MatrixSpace(QQ['t'].fraction_field(), 8).random_element() > > sage: %time D= C*C > > CPU times: user 17.28 s, sys: 0.19 s, total: 17.48 s > > Wall time: 17.57 s > > > Is something wrong ? 17 seconds instead of 0.04 ? 400 times slower ? > > is it my particular system ? is there an option perhaps for performing > > the computations without simplifying the fractions, or something ? > > > (of course this came up in an example more interesting than squaring > > random matrices...) > > > It is my humble opinion that this issue is serious. Rational fractions > > tend to be all over the place in formal computations. > > > any thoughts ? > > This is a known bug, and almost fixed: > > http://trac.sagemath.org/sage_trac/ticket/4000 > > - Robert > > -- > To post to this group, send an email to [email protected] > To unsubscribe from this group, send an email to > [email protected] > For more options, visit this group athttp://groups.google.com/group/sage-devel > URL:http://www.sagemath.org -- To post to this group, send an email to [email protected] To unsubscribe from this group, send an email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
