implement right_kernel() and right_nullity() for matrices

[aghitza]

I implemented right_kernel() and right_nullity() for matrices in the simplest possible way (calling the left_ functions on the transpose of self). This is a tiny little step in the direction of #1607.

Component: linear algebra

Issue created by migration from https://trac.sagemath.org/ticket/2542

[mwhansen]

Attachment: right_kernel.patch.gz

Attachment: 2542-2.patch.gz

[mwhansen]

comment:1

Looks good to me. Apply 2542-2.patch which is rebased against 2.10.4.alpha0.

[sagetrac-mabshoff]

comment:2

This patch causes a doctest failure for me:

sage -t -long devel/sage/sage/matrix/matrix2.pyx
**********************************************************************
File "matrix2.pyx", line 1170:
    sage: A.right_nullity()
Expected:
    1
Got:
    0
**********************************************************************
1 items had failures:
   1 of   4 in __main__.example_26
***Test Failed*** 1 failures.
For whitespace errors, see the file .doctest_matrix2.pyx

Cheers,

Michael

[sagetrac-mabshoff]

comment:3

[06:34] <mhansen> mabshoff: For 2542, the doctest is wrong and the answer returned is correct.

Cheers,

Michael

[sagetrac-mabshoff]

comment:4

Merged 2542-2.patch with corrected doctest in Sage 2.10.4.rc0