1 ## Copyright (C) 1994-2012 John W. Eaton
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{map} =} gray ()
21 ## @deftypefnx {Function File} {@var{map} =} gray (@var{n})
22 ## Create gray colormap. This colormap varies from black to white with
24 ## The argument @var{n} must be a scalar.
25 ## If unspecified, the length of the current colormap, or 64, is used.
28 ## Author: Tony Richardson <arichard@stark.cc.oh.us>
32 function map = gray (n)
38 error ("gray: argument must be a scalar");
46 map = [ gr, gr, gr ] / (n - 1);
51 %! ## Show the 'gray' colormap as an image
52 %! image (1:64, linspace (0, 1, 64), repmat (1:64, 64, 1)')
53 %! axis ([1, 64, 0, 1], "ticy", "xy")
54 %! colormap (gray (64))