On Oct 24, 2006, at 7:25 AM, Bill Hart wrote:
> > David, did your comparative GMP/Magma timings take into account this > MAGMA binary issue, which I presume William told you about? I.e. which > binary of MAGMA did you measure against? I'm not sure. I think it must have been the V12, 64-bit one. I can run them all again if you like, but it might take a day or two in between everything else. BTW if you are running tests on sage.math, be aware that the default version of GMP on sage.math is not the latest, it's only something like 4.1.3. You should link against the versions in the SAGE distribution, or compile GMP 4.2.1 yourself. It *does* make a difference. > It interests me that MAGMA appears 2 times faster for some bit > lengths. > It doesn't seem possible if they are actually using GMP for the > multiplications, though I note for the range we are really interested > in, the timings are the same. I recall that MAGMA seems to switch algorithms when at least one of the integers goes beyond about 1700 bits. Suddenly it jumps in speed by a factor of 2 or 4 or something. GMP has no such discontinuity. You can see this on the graph http://sage.math.washington.edu/home/dmharvey/magma-vs-everyone/ZZ- mult/graph.png i.e. the vertical line. David --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
