On Saturday, August 6, 2011, Jacob Schlather <[email protected]> wrote: >>It sounds like your copy of Sage is incorrectly installed. It would >>be helpful to provide tons of useful information about >>your sage install. > > This is entirely probable. I unzipped the sage-4.7-linux-64bit- > ubuntu_10.04.1_lts-x86_64-Linux, > into a folder and have been using the pre-compiled binary. I'm > currently running 64 bit Ubuntu 10.10 - Maverick. I am running python > 2.6.6 though, which could possibly be an issue. Sorry about the > inconvenient form of the matrix, I had just grabbed the output. And > I'm also segfaulting if I just do a random matrix (such as your > example). So it's definitely an issue with my install or that I'm > still running python 2.6.6. Perhaps updating to 3.0 will fix it.
Your systemwide python is irrelevant. Try building sage from source. > > On Aug 6, 3:05 am, William Stein <[email protected]> wrote: >> On Fri, Aug 5, 2011 at 10:34 PM, Jacob Schlather >> >> <[email protected]> wrote: >> > I'm having a bit of a strange issue, I'm working on something where I >> > need to find the rank of a somewhat large matrix over a finite field. >> > I recall testing sage's capabilities when I was looking at how I was >> > going to take the rank and remember sage taking the rank of matrices >> > much larger than the one that's giving me trouble. Anyway the matrix >> > I'm having an issue with is in the following file >> >https://docs.google.com/leaf?id=0B_KM7xCfSwolYmQ4YTEzYjItYTNiZC00MTAx... >> > . >> >> It is an interesting exercise just to load that matrix into Sage, >> given the way you provided it. >> It would have been much nicer to provide a link to a pickle, or >> sage_input, or convert >> the matrix to a list first or something. Anyway, after downloading >> your matrix, I can make the >> corresponding Sage matrix as follows, I think: >> >> sage: a = open('Matrix.dat').readlines()[1:] >> sage: a = ''.join(open('Matrix.dat').readlines()[1:]).replace('[','').replace(']\n',' ,').replace(' >> ',',') >> sage: m = matrix(GF(5), 255,121, eval('['+a+']')) >> >> I then try to compute the rank, and it seems to give me the answer instantly: >> >> sage: time m.rank() >> 121 >> Time: CPU 0.01 s, Wall: 0.01 s >> >> The answer seems very reasonable, since it would be the answer for a >> random matrix of that size. >> But who knows, maybe I read your matrix in incorrectly. >> >> > The program works like a charm for matrices of smaller sizes, during >> > this run it will get up to around size 381*70 before crashing. If I'm >> > working over GF(7) then it's segfaulting for a matrix the size of 180 >> > x 116. It's possible that the error is somehow hidden in my program, >> >> sage: a = random_matrix(GF(7), 180, 116) >> sage: time a.rank() >> 116 >> Time: CPU 0.00 s, Wall: 0.00 s >> >> It sounds like your copy of Sage is incorrectly installed. It would >> be helpful to provide tons of useful information about >> your sage install. >> >> >> >> >> >> >> >> >> >> > in the off chance I've uploaded it here as well >> >https://docs.google.com/leaf?id=0B_KM7xCfSwolY2UxNDA4OGQtZTJhZS00ZDBl... >> > . The offending inputs would be >> > Lambda(5,5,5,1) and Lambda(7,4,7,1), of course increase the majority >> > of those values will also give the same error. >> >> > The error message I'm getting is: >> >> > RuntimeError Traceback (most recent call >> > last) >> >> > /media/Media/Sage/sage-4.7-linux-64bit-ubuntu_10.04.1_lts-x86_64-Linux/ >> > <ipython console> in <module>() >> >> > /media/Media/Sage/sage-4.7-linux-64bit-ubuntu_10.04.1_lts-x86_64-Linux/ >> > <string> in Lambda(q, m, k, r) >> >> > /media/Media/Sage/sage-4.7-linux-64bit-ubuntu_10.04.1_lts-x86_64-Linux/ >> > local/lib/python2.6/site-packages/sage/matrix/matrix_modn_dense.so in >> > sage.matrix.matrix_modn_dense.Matrix_modn_dense.rank (sage/matrix/ >> > matrix_modn_dense.c:11595)() >> >> > RuntimeError: Segmentation fault >> >> > -- >> > To post to this group, send email to [email protected] >> > To unsubscribe from this group, send email to [email protected] >> > For more options, visit this group athttp:// groups.google.com/group/sage-support >> > URL:http://www.sagemath.org >> >> -- >> William Stein >> Professor of Mathematics >> University of Washingtonhttp://wstein.org > > -- > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to [email protected] > For more options, visit this group at http://groups.google.com/group/sage-support > URL: http://www.sagemath.org > -- William Stein Professor of Mathematics University of Washington http://wstein.org -- To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
