X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?p=CreaPhase.git;a=blobdiff_plain;f=octave_packages%2Fm%2Fstatistics%2Fbase%2Frunlength.m;fp=octave_packages%2Fm%2Fstatistics%2Fbase%2Frunlength.m;h=b396746ce483ccc7468fadceb20771cccd4d95ec;hp=0000000000000000000000000000000000000000;hb=1c0469ada9531828709108a4882a751d2816994a;hpb=63de9f36673d49121015e3695f2c336ea92bc278 diff --git a/octave_packages/m/statistics/base/runlength.m b/octave_packages/m/statistics/base/runlength.m new file mode 100644 index 0000000..b396746 --- /dev/null +++ b/octave_packages/m/statistics/base/runlength.m @@ -0,0 +1,66 @@ +## Copyright (C) 2005-2012 Paul Kienzle +## +## 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} {[count, value] =} runlength (@var{x}) +## Find the lengths of all sequences of common values. Return the +## vector of lengths and the value that was repeated. +## +## @example +## @group +## runlength ([2, 2, 0, 4, 4, 4, 0, 1, 1, 1, 1]) +## @result{} [2, 1, 3, 1, 4] +## @end group +## @end example +## @end deftypefn + +function [count, value] = runlength (x) + + if (nargin != 1) + print_usage (); + endif + + if (!(isnumeric (x) || islogical (x)) || !isvector (x)) + error ("runlength: X must be a numeric vector"); + endif + + if (iscolumn (x)) + x = x.'; + endif + + idx = [find(x(1:end-1) != x(2:end)), length(x)]; + count = diff ([0 idx]); + if (nargout == 2) + value = x(idx); + endif + +endfunction + + +%!assert (runlength([2 2 0 4 4 4 0 1 1 1 1]), [2 1 3 1 4]); +%!assert (runlength([2 2 0 4 4 4 0 1 1 1 1]'), [2 1 3 1 4]); +%!test +%! [c, v] = runlength ([2 2 0 4 4 4 0 1 1 1 1]); +%! assert (c, [2 1 3 1 4]); +%! assert (v, [2 0 4 0 1]); + +%% Test input validation +%!error runlength () +%!error runlength (1, 2) +%!error runlength (['A'; 'B']) +%!error runlength (ones(2,2))