Mercurial > octave
view scripts/image/bone.m @ 27919:1891570abac8
update Octave Project Developers copyright for the new year
In files that have the "Octave Project Developers" copyright notice,
update for 2020.
author | John W. Eaton <jwe@octave.org> |
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date | Mon, 06 Jan 2020 22:29:51 -0500 |
parents | b442ec6dda5c |
children | bd51beb6205e |
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## Copyright (C) 1999-2020 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this distribution ## or <https://octave.org/COPYRIGHT.html/>. ## ## ## 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} =} bone () ## @deftypefnx {} {@var{map} =} bone (@var{n}) ## Create color colormap. This colormap varies from black to white with ## gray-blue shades. ## ## The argument @var{n} must be a scalar. ## If unspecified, the length of the current colormap, or 64, is used. ## @seealso{colormap} ## @end deftypefn ## Author: Kai Habel <kai.habel@gmx.de> function map = bone (n) if (nargin > 1) print_usage (); elseif (nargin == 1) if (! isscalar (n)) error ("bone: N must be a scalar"); endif n = double (n); else hf = get (0, "currentfigure"); if (! isempty (hf)) n = rows (get (hf, "colormap")); else n = 64; endif endif if (n == 1) map = [1/8 1/8 1/8]; elseif (n == 2) map = [1/16 1/8 1/8 1 1 1 ]; elseif (n > 2) x = [0:n-1]' / (n-1); idx = floor (3/4*n); nel = n - idx + 1; # number of elements rem = mod (n, 8); switch (rem) case {2, 4} base = 1 / (16 + 2*(n-rem)); case {5, 7} base = 1 / (24 + 2*(n-rem)); otherwise base = 0; endswitch r(1:idx,1) = 7/8 * x(1:idx); r(idx:n,1) = linspace (7/8 * x(idx) + base, 1, nel); idx = floor (3/8 * n); nel = idx + 1; g(1:idx,1) = 7/8 * x(1:idx); g(idx:2*idx,1) = linspace (7/8 * x(idx), 7/8 * x(2*idx) + 1/8, nel); g(2*idx+1:n,1) = 7/8 * x(2*idx+1:n) + 1/8; base = 1 / (8*idx); nel = idx; b(1:idx,1) = linspace (base, 7/8 * x(idx) + 1/8, nel); b(idx:n,1) = 7/8 * x(idx:n) + 1/8; map = [r, g, b]; else map = zeros (0, 3); endif endfunction %!demo %! ## Show the 'bone' colormap profile and as an image %! cmap = bone (256); %! subplot (2, 1, 1); %! rgbplot (cmap, "composite"); %! subplot (2, 1, 2); %! rgbplot (cmap);