id summary reporter owner description type status priority milestone component resolution keywords cc merged author reviewer upstream work_issues branch commit dependencies stopgaps
13012 MatrixSpace is too eager to construct zero matrices novoselt jason was "This is a follow up to #10793 where it was prohibited to silently change dimensions of a matrix preserving the number of entries (e.g. 3x2 to 2x3). Here is the problem with zeros:
{{{
sage: m = zero_matrix(2, 3)
sage: m
[0 0 0]
[0 0 0]
sage: M = MatrixSpace(ZZ, 3, 5)
sage: M.zero()
[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]
sage: M(m)
[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]
}}}
The last line should have raised an exception. I'm writing a patch." defect closed major sage-5.1 linear algebra fixed sd40.5 vbraun kcrisman rbeezer sage-5.1.beta5 Andrey Novoseltsev William Stein N/A