empty matrices: smith_form() throws a RuntimeError

[dfdeshom]

sage: m = matrix([])
sage: m.smith_form()
<type 'exceptions.RuntimeError'>:

Component: linear algebra

Issue created by migration from https://trac.sagemath.org/ticket/3068

[dfdeshom]

comment:1

This seems to be gone as of 3.1.1. Could someone close this?

sage: m = matrix([])
sage: m.smith_form()
 ([], [], [])

[loefflerd]

comment:2

In 3.2.2.alpha0 this works fine as long as the matrix has 0 rows and 0 columns, but for 0 rows and a nonzero number of columns (or vice versa) we still get the error. This arises from the fact that Pari doesn't have the notion of a matrix with 0 rows and 1 column, so the matrix gets "truncated" (!) before being passed to Pari.

I will fix this as part of #4681.

[sagetrac-mabshoff]

comment:3

Hi David,

usually the release manager does the closing of a ticket once the fix has been merged. Until then it stays open.

Cheers,

Michael

[loefflerd]

comment:4

I'm sorry for overstepping my authority. Anyway, the fix is now up at #4681.

[sagetrac-mabshoff]

comment:5

Replying to @loefflerd:

I'm sorry for overstepping my authority. Anyway, the fix is now up at #4681.

Don't worry about it because it is one of those unwritten rules :)

Cheers,

Michael

[sagetrac-mabshoff]

comment:6

Fixed in Sage 3.2.2.alpha1 via #4681.

Cheers,

Michael