sage: version() 'Sage Version 4.8, Release Date: 2012-01-20' sage: L = [-4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -9, 9, 1, 0, 0, 0, 0, 0, 0, 2, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -9, 9, 1, 0, 0, 0, 0, 0, 0, 2, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -9, 9, 1, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -9, 9, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -9, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -12, 0, 0, 0, 0, 1, 0, 0, 0, 18, 3, 0, 0, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, -18, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, -12, 0, 0, 0, 9, 1, 0, 0, -9, 18, 3, 0, 0, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, -18, 9, 0, 0, 6, 0, 0, 0, 0, 0, 0, -4, 2, -12, 0, 0, -9, 9, 1, 0, 0, -9, 18, 3, 0, 2, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, -18, 9, 0, 0, 6, 0, 0, 0, 0, 0, 0, -4, 2, -12, 0, 0, -9, 9, 1, 0, 0, -9, 18, 3, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -18, 9, 0, 0, 6, 0, 0, 0, 0, 0, 0, -4, 2, -12, 0, 0, -9, 9, 0, 0, 0, -9, 18, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -18, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, -4, 2, 0, 0, 0, -9, 0, 0, 0, 0, -9, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -4, 0, 0, 0, 0, -12, 0, 0, 0, 0, 3, 0, 0, 0, -4, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 9, 0, 0, 0, 0, 0, 0, -6, 0, 0, 0, 0, -12, 0, 0, 0, 1, -12, 0, 0, 0, 18, 3, 0, 0, 0, -4, 0, 0, 0, 0, -4, 1, 0, 0, 0, -18, 9, 0, 0, 0, 0, 0, -6, -6, 0, 0, 0, 2, -12, 0, 0, 0, 1, -12, 0, 0, -9, 18, 3, 0, 0, 0, -4, 0, 0, 0, 0, -4, 1, 0, 0, 0, -18, 9, 0, 6, 0, 0, 0, -6, -6, 0, 0, -4, 2, -12, 0, 0, 0, 1, -12, 0, 0, -9, 18, 3, 2, 0, 0, 0, 0, 0, 0, 0, -4, 1, 0, 0, 0, -18, 9, 0, 6, 0, 0, 0, -6, -6, 0, 0, -4, 2, -12, 0, 0, 0, 1, -12, 0, 0, -9, 18, 0, 2, 0, 0, 0, 0, 0, 0, 0, -4, 1, 0, 0, 0, -18, 0, 0, 6, 0, 0, 0, -6, -6, 0, 0, -4, 2, 0, 0, 0, 0, 1, 0, 0, 0, -9, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -6, 0, 0, 0, -4, -2, 0, 0, 0, 0, -12, 0, 0, 0, 3, 0, 0, -4, 0, 0, -2, 0, 0, 0, 0, 1, 0, 0, 0, 9, 0, 0, -12, 0, 0, 0, 0, -6, 0, 0, 0, 0, -2, 0, 0, 0, 1, -12, 0, 0, 18, 3, 0, 0, -4, 0, 0, -2, 0, 0, 0, -4, 1, 0, 0, -18, 9, 0, 0, -12, 0, 0, 0, -6, -6, 0, 0, 0, 0, -2, 0, 0, 0, 1, -12, 0, -9, 18, 3, 0, 0, 0, 0, 0, -2, 0, 0, 0, -4, 1, 0, 0, -18, 9, 0, 0, -12, 0, 0, 0, -6, -6, 0, 0, 0, 0, -2, 0, 0, 0, 1, -12, 0, -9, 18, 2, 0, 0, 0, 0, 0, -2, 0, 0, 0, -4, 1, 0, 0, -18, 0, 0, 0, -12, 0, 0, 0, -6, -6, 0, 0, 0, 0, -2, 0, 0, 0, 1, 0, 0, -9, 0, 2, 0, 0, 0, 0, 0, -2, 0, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, -12, 0, 0, 0, -6, 0, 0, 0, 0, 0, -2, 0, 0, 0, -12, 0, 0, 3, 0, -4, 0, 0, 0, 0, 0, -2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, -12, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 1, -12, 0, 18, 3, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, -4, 1, 0, 0, 0, 0, 0, 0, 0, -12, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 1, -12, -9, 18, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, -4, 1, 0, 0, 0, 0, 0, 0, 0, -12, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 1, 0, -9, 2, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, -4, 0, 0, 0, 0, 0, 0, 0, 0, -12, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, -12, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 1, -12, 18, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 1, -9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, -12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
sage: M = Matrix(ZZ, 36, 36, L) sage: M.rref().det() 1 sage: M.det() [..... still no answer after one minute .....] But sage is perfectly happy to compute an integer determinant of a random matrix of that size. So my matrix must be very special! And it can compute the characteristic polynomial of my matrix almost instantly (so at least I can get on with my work). Same thing happens with version 5.3 on sage.math. Any ideas? david -- You received this message because you are subscribed to the Google Groups "sage-support" group. 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. Visit this group at http://groups.google.com/group/sage-support?hl=en.
