1## Copyright (C) 2000 Kai Habel <kai.habel@gmx.de>
2##
3## This program is free software; you can redistribute it and/or modify it under
4## the terms of the GNU General Public License as published by the Free Software
5## Foundation; either version 3 of the License, or (at your option) any later
6## version.
7##
8## This program is distributed in the hope that it will be useful, but WITHOUT
9## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10## FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
11## details.
12##
13## You should have received a copy of the GNU General Public License along with
14## this program; if not, see <http://www.gnu.org/licenses/>.
15
16## -*- texinfo -*-
17## @deftypefn {Function File} @var{s}= std2 (@var{I})
18## Returns the standard deviation for a 2d real type matrix.
19## Uses @code{std (I(:))}
20## @seealso{mean2,std}
21## @end deftypefn
22
23function s = std2 (I)
24
25  if !(nargin == 1)
26    print_usage ();
27  endif
28
29  if (! isreal (I))
30    error("std2: I be a real type array");
31  endif
32
33  s = std (I(:));
34endfunction
35