Mercurial > octave-nkf

annotate scripts/linear-algebra/dmult.m @ 4960:ce01dbd7e026 ss-2-1-58

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
[project @ 2004-09-02 03:47:49 by jwe]
author jwe
date Thu, 02 Sep 2004 03:47:49 +0000
parents e7da90a1cc11
children 4c8a2e4e0717
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
1 ## Copyright (C) 1995, 1996, 1997 Kurt Hornik
3426
f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe]
jwe
parents: 3191
diff changeset
2 ##
3922
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
3 ## This file is part of Octave.
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
4 ##
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
5 ## Octave is free software; you can redistribute it and/or modify it
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
6 ## under the terms of the GNU General Public License as published by
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
7 ## the Free Software Foundation; either version 2, or (at your option)
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
8 ## any later version.
3426
f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe]
jwe
parents: 3191
diff changeset
9 ##
3922
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
10 ## Octave is distributed in the hope that it will be useful, but
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
3426
f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe]
jwe
parents: 3191
diff changeset
13 ## General Public License for more details.
f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe]
jwe
parents: 3191
diff changeset
14 ##
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
15 ## You should have received a copy of the GNU General Public License
3922
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
16 ## along with Octave; see the file COPYING. If not, write to the Free
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
17 ## Software Foundation, 59 Temple Place - Suite 330, Boston, MA
38c61cbf086c [project @ 2002-05-01 06:48:35 by jwe]
jwe
parents: 3458
diff changeset
18 ## 02111-1307, USA.
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
19
3449
858695b3ed62 [project @ 2000-01-18 04:08:59 by jwe]
jwe
parents: 3426
diff changeset
20 ## -*- texinfo -*-
858695b3ed62 [project @ 2000-01-18 04:08:59 by jwe]
jwe
parents: 3426
diff changeset
21 ## @deftypefn {Function File} {} dmult (@var{a}, @var{b})
858695b3ed62 [project @ 2000-01-18 04:08:59 by jwe]
jwe
parents: 3426
diff changeset
22 ## If @var{a} is a vector of length @code{rows (@var{b})}, return
858695b3ed62 [project @ 2000-01-18 04:08:59 by jwe]
jwe
parents: 3426
diff changeset
23 ## @code{diag (@var{a}) * @var{b}} (but computed much more efficiently).
858695b3ed62 [project @ 2000-01-18 04:08:59 by jwe]
jwe
parents: 3426
diff changeset
24 ## @end deftypefn
3426
f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe]
jwe
parents: 3191
diff changeset
25
3458
d25bc039237b [project @ 2000-01-19 09:36:14 by jwe]
jwe
parents: 3449
diff changeset
26 ## Author: KH <Kurt.Hornik@ci.tuwien.ac.at>
d25bc039237b [project @ 2000-01-19 09:36:14 by jwe]
jwe
parents: 3449
diff changeset
27 ## Description: Rescale the rows of a matrix
3426
f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe]
jwe
parents: 3191
diff changeset
28
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
29 function M = dmult (a, B)
3426
f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe]
jwe
parents: 3191
diff changeset
30
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
31 if (nargin != 2)
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
32 usage ("dmult (a, B)");
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
33 endif
4890
e7da90a1cc11 [project @ 2004-05-06 20:36:29 by jwe]
jwe
parents: 3922
diff changeset
34 if (! isvector (a))
3458
d25bc039237b [project @ 2000-01-19 09:36:14 by jwe]
jwe
parents: 3449
diff changeset
35 error ("dmult: a must be a vector of length rows (B)");
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
36 endif
4890
e7da90a1cc11 [project @ 2004-05-06 20:36:29 by jwe]
jwe
parents: 3922
diff changeset
37 a = a(:);
e7da90a1cc11 [project @ 2004-05-06 20:36:29 by jwe]
jwe
parents: 3922
diff changeset
38 sb = size (B);
e7da90a1cc11 [project @ 2004-05-06 20:36:29 by jwe]
jwe
parents: 3922
diff changeset
39 sb(1) = 1;
e7da90a1cc11 [project @ 2004-05-06 20:36:29 by jwe]
jwe
parents: 3922
diff changeset
40 M = repmat (a(:), sb) .* B;
3191
e4f4b2d26ee9 [project @ 1998-10-23 05:43:59 by jwe]
jwe
parents:
diff changeset
41 endfunction