X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?p=CreaPhase.git;a=blobdiff_plain;f=octave_packages%2Fm%2Fimage%2Fflag.m;fp=octave_packages%2Fm%2Fimage%2Fflag.m;h=e8f34e2b53e5a2854af6cbc31c36025375a37cd7;hp=0000000000000000000000000000000000000000;hb=1c0469ada9531828709108a4882a751d2816994a;hpb=63de9f36673d49121015e3695f2c336ea92bc278 diff --git a/octave_packages/m/image/flag.m b/octave_packages/m/image/flag.m new file mode 100644 index 0000000..e8f34e2 --- /dev/null +++ b/octave_packages/m/image/flag.m @@ -0,0 +1,59 @@ +## Copyright (C) 1999-2012 Kai Habel +## +## 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 +## . + +## -*- texinfo -*- +## @deftypefn {Function File} {@var{map} =} flag () +## @deftypefnx {Function File} {@var{map} =} flag (@var{n}) +## Create color colormap. This colormap cycles through red, white, blue +## and black with each index change. +## 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 + +function map = flag (n) + + if (nargin == 0) + n = rows (colormap); + elseif (nargin == 1) + if (! isscalar (n)) + error ("flag: argument must be a scalar"); + endif + else + print_usage (); + endif + + p = [1, 0, 0; 1, 1, 1; 0, 0, 1; 0, 0, 0]; + if (rem(n,4) == 0) + map = kron (ones (n / 4, 1), p); + else + m1 = kron (ones (fix (n / 4), 1), p); + m2 = p(1:rem (n, 4), :); + map = [m1; m2]; + endif + +endfunction + +%!demo +%! ## Show the 'flag' colormap as an image +%! image (1:64, linspace (0, 1, 64), repmat (1:64, 64, 1)') +%! axis ([1, 64, 0, 1], "ticy", "xy") +%! colormap (flag (64)) +