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## -*- texinfo -*-
## @deftypefn {} {@var{p} =} colperm (@var{s})
## Return the column permutations such that the columns of
## @code{@var{s}(:, @var{p})} are ordered in terms of increasing number of
## nonzero elements.
##
## If @var{s} is symmetric, then @var{p} is chosen such that
## @code{@var{s}(@var{p}, @var{p})} orders the rows and columns with
## increasing number of nonzero elements.
## @end deftypefn

function p = colperm (s)

  if (nargin < 1)
    print_usage ();
  endif

  [~, p] = sort (sum (s != 0, 1));

endfunction


%!assert <*59226> (colperm ([1,0;0,0]), [2, 1])