I have to run somewhere for a little while, but I just realized that there might be a bug for small input (1000 being small enough). You may want to try something bigger to see if it works correctly.
Also, at http://developer.apple.com/documentation/DeveloperTools/Conceptual/LowLevelABI/Articles/32bitPowerPC.html I found the following: (*) In Mac OS X v10.4 and later and GCC 4.0 and later, the size of the long double extended precision data type is 16 bytes (itÂ’s made up of two 8-byte doubles). In earlier versions of Mac OS X and GCC, long double is equivalent to double. You should not use the long double type when you use GCC 4.0 or later to develop or in programs targeted at Mac OS X versions earlier than 10.4. I'll probably be back looking at this in a little while. On Sun, 2007-10-14 at 14:53 -0700, William Stein wrote: > On 10/14/07, Jonathan Bober <[EMAIL PROTECTED]> wrote: > > > > I'm not sure right now, but I'm thinking about it. > > > > You could try setting > > > > long_double_precision = double_precision > > > > wherever it is initialized. (This is around line 140 somewhere.) If you > > do this it will just skip the part of the computation where it uses long > > doubles (For some reason I have a feeling that there might be something > > funny about the long double type on PPC OS X - but I don't know what > > that reason is, so I could be wrong.) > > Hi, > > It turns out that number_of_partitions with your algorithm is wrong > for input 1000 on x86_64, but *right* on ppc... > This threw me off for a while. I kept trying to lower precision > on ppc with my test case being 1000 and of course it was always > right on ppc but wrong on x86_64, so I thought the opposite. > > > > > > Similarly, you could play with setting qd_precision = dd_precision to > > skip the part of the computation with quad_doubles, or set everything to > > double_precision, so that it only uses either mpfr or standard doubles, > > etc. > > > > Another thing to try is using just a little bit more precision. See > > around line 572, in the function compute_extra_precision(). You could > > turn the 5 into, say, a 15 or a 30 to see what happens. If that works, > > then you can try to experiment to see what the smallest number that > > works is. > > > > On Sun, 2007-10-14 at 14:40 -0600, William Stein wrote: > > > Hi Jon, > > > > > > Your number_of_partitions code is in the current sage-2.8.7.rc1, > > > and it works on all but one machine we tested in on. Unfortunately > > > -- JUST AS YOU SUSPECTED -- it doens't work on PPC OS X. It runs, > > > but gives wrong answers. Any ideas how to fix your code to still > > > work on OS X PPC, even slowly? > > > > > > William > > > > > > > > > > > > > > > > --~--~---------~--~----~------------~-------~--~----~ 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/ -~----------~----~----~----~------~----~------~--~---
