On Fri, Apr 4, 2014 at 2:50 PM, pong <wypon...@gmail.com> wrote: > I want to form the span of a finite sequence of matrices (in the matrix > space). > > I tried: > M = MatrixSpace(QQ,4) > span([M(range(16)), M(range(2,18))]) > > But sage returns: > .... > > TypeError: The base_ring (= [ 2 3 4 5] > [ 6 7 8 9] > [10 11 12 13] > [14 15 16 17]) must be a principal ideal domain. > > What should be the correct way to generate the span in this case?
Completely rewrite the MatrixSpace class to actually be a vector space... sadly it isn't: sage: is_VectorSpace(M) False You'll have to work in QQ^16, e.g., M = MatrixSpace(QQ,4) v = M(range(16)); w = M(range(2,18)) A = QQ^16 v0 = A(v.list()); w0 = A(w.list()) S = span([v0, w0]) M(S.0.list()) You can translate back and forth -- it's a little painful, but will fully work. William > > -- > You received this message because you are subscribed to the Google Groups > "sage-support" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-support+unsubscr...@googlegroups.com. > To post to this group, send email to sage-support@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-support. > For more options, visit https://groups.google.com/d/optout. -- William Stein Professor of Mathematics University of Washington http://wstein.org -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
