--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/sparse/spconvert.m	Fri Feb 25 19:55:28 2005 +0000
@@ -0,0 +1,43 @@
+## Copyright (C) 2004 David Bateman & Andy Adler
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, write to the Free Software
+## Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{x} =} spconvert (@var{m})
+## This function converts for a simple sparse matrix format easily
+## produced by other programs into Octave's internal sparse format. The
+## input @var{x} is either a 3 or 4 column real matrix, containing
+## the row, column, real and imaginary parts of the elements of the
+## sparse matrix. An element with a zero real and imaginay part can
+## be used to force a particular matrix size.
+## @end deftypefn
+
+function s = spconvert (m)
+
+  if issparse(m)
+    s = m;
+  else
+    sz = size(m);
+    if (nargin != 1 || !ismatrix(m) || !isreal(m) || length(sz) != 2 || 
+	(sz(2) != 3 && sz(2) != 4))
+      error ("spconvert: input matrix must be either sparse or a three or four column");
+      error ("           real matrix");
+    elseif (sz(2) == 3)
+      s = sparse (m(:,1), m(:,2), m(:,3));
+    else
+      s = sparse (m(:,1), m(:,2), m(:,3) + 1i*m(:,4));
+    endif
+  endif
+endfunction