--- /dev/null
+function resu = df_check_char_array(x, nelem, required)
+
+ %# auxiliary function: pad a char array to some width
+
+ %% Copyright (C) 2009-2012 Pascal Dupuis <Pascal.Dupuis@uclouvain.be>
+ %%
+ %% This file is part of Octave.
+ %%
+ %% Octave 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, or (at your option) any later version.
+ %%
+ %% Octave 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 Octave; see the file COPYING. If not,
+ %% write to the Free Software Foundation, 51 Franklin Street -
+ %% Fifth Floor, Boston, MA 02110-1301, USA.
+
+ %#
+ %# $Id: df_check_char_array.m 9585 2012-02-05 15:32:46Z cdemills $
+ %#
+
+ if 2 == nargin, required = [nelem 1]; endif
+
+ if nelem < required(1),
+ error("Too many elements to assign");
+ endif
+
+ %# a zero-length element is still considered as a space by char
+ if isempty(x), x = ' '; endif
+
+ if size(x, 1) < max(required(1), nelem)
+ %# pad vertically
+ dummy = repmat(' ', nelem-size(x, 1), 1);
+ resu = char(x, dummy);
+ else
+ resu = x;
+ endif
+
+ if size(resu, 2) < required(2),
+ %# pad horizontally
+ dummy = repmat(' ', nelem, required(2)-size(resu, 2));
+ resu = horzcat(resu, dummy);
+ endif
+
+endfunction