Mercurial > octave
view scripts/image/cool.m @ 33528:6813c5c7e1b9 default tip @
Update to gnulib revision 6213c5bd72d15ca5e1ea9c34122899e02fed448c.
* bootstrap.conf: Update GNULIB_REVISION that contains a fix for a build issue
when targeting Cygwin.
author | Markus Mützel <markus.muetzel@gmx.de> |
---|---|
date | Fri, 03 May 2024 16:04:05 +0200 |
parents | d8e5e55c3cf5 |
children |
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######################################################################## ## ## Copyright (C) 1999-2024 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this ## distribution or <https://octave.org/copyright/>. ## ## 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 3 of the License, 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, see ## <https://www.gnu.org/licenses/>. ## ######################################################################## ## -*- texinfo -*- ## @deftypefn {} {@var{map} =} cool () ## @deftypefnx {} {@var{map} =} cool (@var{n}) ## Create color colormap. The colormap varies from cyan to magenta. ## ## The argument @var{n} must be a scalar. ## If @var{n} is not specified the length of the current colormap is used. If ## there is no current colormap the default value of 256 is used. ## @seealso{colormap} ## @end deftypefn function map = cool (n) if (nargin == 1) if (! (isscalar (n) && isreal (n) && n == fix (n))) error ("cool: N must be a scalar integer"); endif n = double (n); else hf = get (0, "currentfigure"); if (! isempty (hf)) n = rows (get (hf, "colormap")); else n = 256; endif endif if (n == 1) map = [0, 1, 1]; elseif (n > 1) r = [0:(n-1)]' / (n - 1); g = 1 - r; b = ones (n, 1); map = [r, g, b]; else map = zeros (0, 3); endif endfunction %!demo %! ## Show the 'cool' colormap profile and as an image %! cmap = cool (256); %! subplot (2, 1, 1); %! rgbplot (cmap, "composite"); %! subplot (2, 1, 2); %! rgbplot (cmap); %!assert (size (cool ()), [256, 3]) %!assert (size (cool (16)), [16, 3]) %!assert (cool (1), [0, 1, 1]) %!assert (cool (true), double ([0, 1, 1])) %!assert (cool (char (1)), double ([0, 1, 1])) %!assert (cool (int32 (1)), double ([0, 1, 1])) %!assert (cool (0), zeros (0, 3)) %!assert (cool (-1), zeros (0, 3)) %!assert (cool (11), [[0:0.1:1]; [1:-0.1:0]; ones(1,11)]', eps) ## Input validation %!error <N must be a scalar integer> cool ("foo") %!error <N must be a scalar integer> cool ([1, 2, 3]) %!error <N must be a scalar integer> cool ({1, 2, 3})