Mercurial > hg > octave-terminal
changeset 10536:74cb77f0a163
update NEWS
author | Jaroslav Hajek <highegg@gmail.com> |
---|---|
date | Tue, 20 Apr 2010 09:03:26 +0200 |
parents | 3f973f6c841c |
children | fdf28dae0f37 |
files | ChangeLog NEWS |
diffstat | 2 files changed, 24 insertions(+), 0 deletions(-) [+] |
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--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,7 @@ +2010-04-20 Jaroslav Hajek <highegg@gmail.com> + + * NEWS: Update. + 2010-04-16 David Bateman <dbateman@free.fr> * PROJECTS: Update for new sparse functionality.
--- a/NEWS +++ b/NEWS @@ -239,6 +239,26 @@ ** rem and mod are now built-in functions. They also handle integer types efficiently using integer arithmetic. + ** Sparse indexing and indexed assignment has been mostly rewritten. + Since Octave uses compressed column storage for sparse matrices, + major attention is devoted to operations manipulating whole columns. + Such operations are now significantly faster, as well as some other + important cases. + + Further, it is now possible to pre-allocate a sparse matrix and + subsequently fill it by assignments, provided they meet certain + conditions. For more information, consult the `spalloc' function, + which is no longer a mere dummy. Consequently, nzmax and nnz are no + longer always equal in Octave. Octave may also produce a matrix with + nnz < nzmax as a result of other operations, so you should + consistently use nnz unless you really want to use nzmax + (i.e. the space allocated for nonzero elements). + + Sparse concatenation is also affected, and concatenating sparse + matrices, especially larger collections, is now significantly more + efficient. This applies to both the [] operator and the + cat/vertcat/horzcat functions. + Summary of important user-visible changes for version 3.2: ---------------------------------------------------------