Mercurial > octave
changeset 25036:fa2f8ffd088e stable
Add note about the preferred way to call lu with sparse input (bug #53390).
* lu.cc: Add strong note to documentation that lu with sparse input should
request four outputs.
| author | Rik <rik@octave.org> |
|---|---|
| date | Wed, 28 Mar 2018 08:57:11 -0700 |
| parents | 6e4121c39957 |
| children | 1c077d652c57 |
| files | libinterp/corefcn/lu.cc |
| diffstat | 1 files changed, 7 insertions(+), 7 deletions(-) [+] |
line wrap: on
line diff
--- a/libinterp/corefcn/lu.cc Wed Mar 28 05:37:45 2018 -0400 +++ b/libinterp/corefcn/lu.cc Wed Mar 28 08:57:11 2018 -0700 @@ -103,14 +103,14 @@ The matrix is not required to be square. When called with two or three output arguments and a sparse input matrix, -@code{lu} does not attempt to perform sparsity preserving column -permutations. Called with a fourth output argument, the sparsity -preserving column transformation @var{Q} is returned, such that -@code{@var{P} * @var{A} * @var{Q} = @var{L} * @var{U}}. +@code{lu} does not attempt to perform sparsity preserving column permutations. +Called with a fourth output argument, the sparsity preserving column +transformation @var{Q} is returned, such that +@code{@var{P} * @var{A} * @var{Q} = @var{L} * @var{U}}. This is the +@strong{preferred} way to call @code{lu} with sparse input matrices. -Called with a fifth output argument and a sparse input matrix, -@code{lu} attempts to use a scaling factor @var{R} on the input matrix -such that +Called with a fifth output argument and a sparse input matrix, @code{lu} +attempts to use a scaling factor @var{R} on the input matrix such that @code{@var{P} * (@var{R} \ @var{A}) * @var{Q} = @var{L} * @var{U}}. This typically leads to a sparser and more stable factorization.