1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
########################################################################
##
## Copyright (C) 2005-2024 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 {} {count =} runlength (@var{x})
## @deftypefnx {} {[count, value] =} runlength (@var{x})
## Find the lengths of all sequences of common values.
##
## @var{count} is a vector with the lengths of each repeated value.
##
## The optional output @var{value} contains the value that was repeated in
## the sequence.
##
## @example
## @group
## runlength ([2, 2, 0, 4, 4, 4, 0, 1, 1, 1, 1])
## @result{} 2 1 3 1 4
## @end group
## @end example
## @seealso{run_count}
## @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 <Invalid call> runlength ()
%!error runlength (['A'; 'B'])
%!error runlength (ones (2,2))
|
