>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. On Aug 6, 3:05 am, William Stein <wst...@gmail.com> wrote: > On Fri, Aug 5, 2011 at 10:34 PM, Jacob Schlather > > <jacob.schlat...@gmail.com> 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 sage-support@googlegroups.com > > To unsubscribe from this group, send email to > > sage-support+unsubscr...@googlegroups.com > > 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 sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
