1 ## Copyright (C) 2004-2012 David Bateman and Andy Adler
3 ## This file is part of Octave.
5 ## Octave is free software; you can redistribute it and/or modify it
6 ## under the terms of the GNU General Public License as published by
7 ## the Free Software Foundation; either version 3 of the License, or (at
8 ## your option) any later version.
10 ## Octave is distributed in the hope that it will be useful, but
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 ## General Public License for more details.
15 ## You should have received a copy of the GNU General Public License
16 ## along with Octave; see the file COPYING. If not, see
17 ## <http://www.gnu.org/licenses/>.
20 ## @deftypefn {Function File} {@var{p} =} colperm (@var{s})
21 ## Return the column permutations such that the columns of
22 ## @code{@var{s} (:, @var{p})} are ordered in terms of increase number
23 ## of non-zero elements. If @var{s} is symmetric, then @var{p} is chosen
24 ## such that @code{@var{s} (@var{p}, @var{p})} orders the rows and
25 ## columns with increasing number of non zeros elements.
28 function p = colperm (s)
35 idx = find (diff ([j; Inf]) != 0);
36 [dummy, p] = sort (idx - [0; idx(1:(end-1))]);