Mercurial > octave-nkf
changeset 20603:f61c67865d9f
Don't return A for inv (A) when A is a singular Diagonal matrix (bug #46103).
* dDiagMatrix.cc (inverse), fDiagMatrix.cc (inverse): return octave_Inf for the
inverse of a diagonal element whose value is 0.
* test/diag-perm.tst: Add tests for new behavior.
author | Rik <rik@octave.org> |
---|---|
date | Wed, 07 Oct 2015 07:41:44 -0700 |
parents | ea6a1c00763a |
children | 734d446560a8 |
files | liboctave/array/dDiagMatrix.cc liboctave/array/fDiagMatrix.cc test/diag-perm.tst |
diffstat | 3 files changed, 9 insertions(+), 8 deletions(-) [+] |
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--- a/liboctave/array/dDiagMatrix.cc Tue Oct 06 22:14:41 2015 +0200 +++ b/liboctave/array/dDiagMatrix.cc Wed Oct 07 07:41:44 2015 -0700 @@ -280,10 +280,7 @@ for (octave_idx_type i = 0; i < len; i++) { if (elem (i, i) == 0.0) - { - info = -1; - return *this; - } + retval.elem (i, i) = octave_Inf; else retval.elem (i, i) = 1.0 / elem (i, i); }
--- a/liboctave/array/fDiagMatrix.cc Tue Oct 06 22:14:41 2015 +0200 +++ b/liboctave/array/fDiagMatrix.cc Wed Oct 07 07:41:44 2015 -0700 @@ -280,10 +280,7 @@ for (octave_idx_type i = 0; i < len; i++) { if (elem (i, i) == 0.0) - { - info = -1; - return *this; - } + retval.elem (i, i) = octave_Inf; else retval.elem (i, i) = 1.0 / elem (i, i); }
--- a/test/diag-perm.tst Tue Oct 06 22:14:41 2015 +0200 +++ b/test/diag-perm.tst Wed Oct 07 07:41:44 2015 -0700 @@ -263,3 +263,10 @@ %! A = A * I () + A; %! A(6, 4) = nan (); %! assert (full (D - A), D - full (A)); + +## inverse preserves diagonal structure even for singular matrices (bug #46103) +%!test +%! x = diag (1:3); +%! assert (inv (x), diag ([1 1/2 1/3])); +%! x = diag (0:2); +%! assert (inv (x), diag ([Inf 1 1/2]));