octave-nkf: scripts/general/shiftdim.m annotate

annotate scripts/general/shiftdim.m @ 12716:6835bc816ef2

shiftdim.m: Use common idiom for finding first non-singleton dimension. Add tests for function. * shiftdim.m: Use common idiom for finding first non-singleton dimension. Add functional tests to .m file.

author	Rik <octave@nomad.inbox5.com>
date	Tue, 07 Jun 2011 10:04:11 -0700
parents	4d777e05d47c
children	72c96de7a403

rev	line source
11523 fd0a3ac60b0e update copyright notices John W. Eaton <jwe@octave.org> parents: 11472 diff changeset	1 ## Copyright (C) 2004-2011 John Eaton and David Bateman
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	2 ##
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	3 ## This file is part of Octave.
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	4 ##
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	5 ## Octave is free software; you can redistribute it and/or modify it
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	6 ## under the terms of the GNU General Public License as published by
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6547 diff changeset	7 ## the Free Software Foundation; either version 3 of the License, or (at
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6547 diff changeset	8 ## your option) any later version.
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	9 ##
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	10 ## Octave is distributed in the hope that it will be useful, but
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	13 ## General Public License for more details.
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	14 ##
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	15 ## You should have received a copy of the GNU General Public License
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6547 diff changeset	16 ## along with Octave; see the file COPYING. If not, see
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6547 diff changeset	17 ## <http://www.gnu.org/licenses/>.
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	18
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	19 ## -- texinfo --
10793 be55736a0783 Grammarcheck the documentation from m-files. Rik <octave@nomad.inbox5.com> parents: 9245 diff changeset	20 ## @deftypefn {Function File} {@var{y} =} shiftdim (@var{x}, @var{n})
6547 4fb053f24fd6 [project @ 2007-04-19 21:47:40 by jwe] jwe parents: 6046 diff changeset	21 ## @deftypefnx {Function File} {[@var{y}, @var{ns}] =} shiftdim (@var{x})
12639 4d777e05d47c doc: Review and update documentation for "Matrix Manipulation" chapter. Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	22 ## Shift the dimensions of @var{x} by @var{n}, where @var{n} must be
9041 853f96e8008f Cleanup documentation file matrix.texi Rik <rdrider0-list@yahoo.com> parents: 7017 diff changeset	23 ## an integer scalar. When @var{n} is positive, the dimensions of
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	24 ## @var{x} are shifted to the left, with the leading dimensions
9041 853f96e8008f Cleanup documentation file matrix.texi Rik <rdrider0-list@yahoo.com> parents: 7017 diff changeset	25 ## circulated to the end. If @var{n} is negative, then the dimensions
5539 b800ae36fc6a [project @ 2005-11-16 18:45:32 by jwe] jwe parents: 5518 diff changeset	26 ## of @var{x} are shifted to the right, with @var{n} leading singleton
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	27 ## dimensions added.
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	28 ##
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	29 ## Called with a single argument, @code{shiftdim}, removes the leading
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	30 ## singleton dimensions, returning the number of dimensions removed
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	31 ## in the second output argument @var{ns}.
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	32 ##
10821 693e22af08ae Grammarcheck documentation of m-files Rik <octave@nomad.inbox5.com> parents: 10793 diff changeset	33 ## For example:
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	34 ##
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	35 ## @example
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	36 ## @group
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	37 ## x = ones (1, 2, 3);
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	38 ## size (shiftdim (x, -1))
5984 82a73f5dadd9 [project @ 2006-09-12 02:23:37 by jwe] jwe parents: 5642 diff changeset	39 ## @result{} [1, 1, 2, 3]
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	40 ## size (shiftdim (x, 1))
5984 82a73f5dadd9 [project @ 2006-09-12 02:23:37 by jwe] jwe parents: 5642 diff changeset	41 ## @result{} [2, 3]
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	42 ## [b, ns] = shiftdim (x);
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	43 ## @result{} b = [1, 1, 1; 1, 1, 1]
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	44 ## @result{} ns = 1
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	45 ## @end group
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	46 ## @end example
5642 2618a0750ae6 [project @ 2006-03-06 21:26:48 by jwe] jwe parents: 5539 diff changeset	47 ## @seealso {reshape, permute, ipermute, circshift, squeeze}
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	48 ## @end deftypefn
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	49
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	50 function [y, ns] = shiftdim (x, n)
ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	51
5518 a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	52 if (nargin < 1 \|\| nargin > 2)
6046 34f96dd5441b [project @ 2006-10-10 16:10:25 by jwe] jwe parents: 5984 diff changeset	53 print_usage ();
5518 a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	54 endif
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	55
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	56 nd = ndims (x);
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	57 orig_dims = size (x);
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	58
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	59 if (nargin == 1)
12716 6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	60 ## Find the first non-singleton dimension.
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	61 (n = find (orig_dims != 1, 1) - 1) \|\| (n = nd);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	62 elseif (! (isscalar (n) && n == fix (n)))
11472 1740012184f9 Use uppercase for variable names in error() strings to match Info documentation. Only m-files done. Rik <octave@nomad.inbox5.com> parents: 10821 diff changeset	63 error ("shiftdim: N must be a scalar integer");
5518 a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	64 endif
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	65
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	66 if (n >= nd)
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	67 n = rem (n, nd);
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	68 endif
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	69
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	70 if (n < 0)
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	71 singleton_dims = ones (1, -n);
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	72 y = reshape (x, [singleton_dims, orig_dims]);
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	73 elseif (n > 0)
5984 82a73f5dadd9 [project @ 2006-09-12 02:23:37 by jwe] jwe parents: 5642 diff changeset	74 ## We need permute here instead of reshape to shift values in a
82a73f5dadd9 [project @ 2006-09-12 02:23:37 by jwe] jwe parents: 5642 diff changeset	75 ## compatible way.
12716 6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	76 y = permute (x, [n+1:nd 1:n]);
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	77 else
5518 a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	78 y = x;
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	79 endif
5518 a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	80
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	81 ns = n;
a9bd6c31751f [project @ 2005-10-29 04:26:38 by jwe] jwe parents: 5307 diff changeset	82
4894 ab5870f984d9 [project @ 2004-06-03 19:32:02 by jwe] jwe parents: diff changeset	83 endfunction
12716 6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	84
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	85
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	86 %!test
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	87 %! x = rand (1, 1, 4, 2);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	88 %! [y, ns] = shiftdim (x);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	89 %! assert (size (y), [4 2]);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	90 %! assert (ns, 2);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	91 %! assert (shiftdim (y, -2), x);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	92 %! assert (size (shiftdim (x, 2)), [4 2]);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	93 %!assert (size (shiftdim (rand (0, 1, 2))), [0 1 2]);
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	94
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	95 %% Test input validation
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	96 %!error(shiftdim ());
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	97 %!error(shiftdim (1,2,3));
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	98 %!error(shiftdim (1, ones (2)));
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	99 %!error(shiftdim (1, 1.5));
6835bc816ef2 shiftdim.m: Use common idiom for finding first non-singleton dimension. Rik <octave@nomad.inbox5.com> parents: 12639 diff changeset	100

Mercurial > octave-nkf

annotate scripts/general/shiftdim.m @ 12716:6835bc816ef2