Hi all, I have changed the subject to 'partially solved' because i'm guessing that some people must be as naive as me, and following this thread without realizing the following simple fact. (It came to me by looking at the name of the patch we've been discussing).
Partial solution : work with ZZ['t'].fraction_field() instead of QQ['t'].fraction_field(). Then it all works very very fast ! This deserves to be called a "partial" solution inasmuch as sage should not behave like this, but from the point of view of a user, it's pretty satisfactory. Every now and then i'll need to convert some of my data (direct coercion is not always possible), a minor price to pay. Here's an auxilliary question. I was running the same tests this morning on a different system. The same phenomenon occured, but it never took longer than 5 seconds to square an 8x8 random matrix instead of 17s. The 'slow' system was a 2-year-old macbook with sage 4.3, the 'fast' system a slightly more recent mac mini with sage 4.3.2. Anyone can explain the difference in speed ? thanks all, Pierre -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
