I can't seem to download your test matrix, but are you sure you're not confusing left kernel and right kernel? What's M * M.kernel().basis()[0]?
On Fri, Aug 19, 2011 at 10:57 AM, Sucharit <[email protected]> wrote: > I am using Sage to compute homologies of large chain complexes. For this, I > need to compute kernels of matrices over GF(2). > The attached file testmatrix.sage contains the 128 X 120 matrix that I > started with. The first command loads the file. The second command should > output a zero vector, but it does not. > sage: load testmatrix.sage > sage: M.kernel().basis()[0]*M > (0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, > 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, > 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, > 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, > 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1) > I have tried this with Sage versions 4.6, 4.6.2, 4.7 and the latest 4.7.1. I > tried this on two computers: one runs Ubuntu 10.04 and one runs a generic > Linux with everything compiled from source. > I would be extremely grateful if someone figures this out. Thanks in > advance, > Sucharit > > -- > 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 > -- 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
