octave-nkf: scripts/statistics/base/median.m annotate

annotate scripts/statistics/base/median.m @ 12575:d0b799dafede

Grammarcheck files for 3.4.1 release.

author	Rik <octave@nomad.inbox5.com>
date	Mon, 04 Apr 2011 15:33:46 -0700
parents	c792872f8942
children	6b2f14af2360

rev	line source
11523 fd0a3ac60b0e update copyright notices John W. Eaton <jwe@octave.org> parents: 11436 diff changeset	1 ## Copyright (C) 1996-2011 John W. Eaton
fd0a3ac60b0e update copyright notices John W. Eaton <jwe@octave.org> parents: 11436 diff changeset	2 ## Copyright (C) 2009-2010 VZLU Prague
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	3 ##
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	4 ## This file is part of Octave.
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	5 ##
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	6 ## Octave is free software; you can redistribute it and/or modify it
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	7 ## 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: 6754 diff changeset	8 ## the Free Software Foundation; either version 3 of the License, or (at
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6754 diff changeset	9 ## your option) any later version.
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	10 ##
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	11 ## Octave is distributed in the hope that it will be useful, but
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	12 ## WITHOUT ANY WARRANTY; without even the implied warranty of
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	14 ## General Public License for more details.
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	15 ##
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	16 ## 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: 6754 diff changeset	17 ## along with Octave; see the file COPYING. If not, see
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6754 diff changeset	18 ## <http://www.gnu.org/licenses/>.
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	19
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	20 ## -- texinfo --
10687 a8ce6bdecce5 Improve documentation strings. Rik <octave@nomad.inbox5.com> parents: 10655 diff changeset	21 ## @deftypefn {Function File} {} median (@var{x})
a8ce6bdecce5 Improve documentation strings. Rik <octave@nomad.inbox5.com> parents: 10655 diff changeset	22 ## @deftypefnx {Function File} {} median (@var{x}, @var{dim})
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	23 ## Compute the median value of the elements of the vector @var{x}.
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	24 ## If the elements of @var{x} are sorted, the median is defined
6754 451b346d8c2f [project @ 2007-06-25 17:31:46 by jwe] jwe parents: 6046 diff changeset	25 ## as
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	26 ## @tex
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	27 ## $$
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	28 ## {\rm median} (x) =
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	29 ## \cases{x(\lceil N/2\rceil), & $N$ odd;\cr
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	30 ## (x(N/2)+x(N/2+1))/2, & $N$ even.}
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	31 ## $$
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	32 ## @end tex
8517 81d6ab3ac93c Allow documentation tobe built for other formats than tex and info sh@sh-laptop parents: 7411 diff changeset	33 ## @ifnottex
3426 f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe] jwe parents: 3408 diff changeset	34 ##
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	35 ## @example
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	36 ## @group
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	37 ## x(ceil(N/2)), N odd
3426 f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe] jwe parents: 3408 diff changeset	38 ## median(x) =
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	39 ## (x(N/2) + x((N/2)+1))/2, N even
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	40 ## @end group
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	41 ## @end example
10821 693e22af08ae Grammarcheck documentation of m-files Rik <octave@nomad.inbox5.com> parents: 10687 diff changeset	42 ##
8517 81d6ab3ac93c Allow documentation tobe built for other formats than tex and info sh@sh-laptop parents: 7411 diff changeset	43 ## @end ifnottex
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	44 ## If @var{x} is a matrix, compute the median value for each
9051 1bf0ce0930be Grammar check TexInfo in all .m files Rik <rdrider0-list@yahoo.com> parents: 8920 diff changeset	45 ## column and return them in a row vector. If the optional @var{dim}
6754 451b346d8c2f [project @ 2007-06-25 17:31:46 by jwe] jwe parents: 6046 diff changeset	46 ## argument is given, operate along this dimension.
12575 d0b799dafede Grammarcheck files for 3.4.1 release. Rik <octave@nomad.inbox5.com> parents: 11587 diff changeset	47 ## @seealso{mean, mode}
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 3200 diff changeset	48 ## @end deftypefn
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	49
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	50 ## Author: jwe
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	51
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	52 function retval = median (x, dim)
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	53
4852 404c7122853e [project @ 2004-04-06 17:23:37 by jwe] jwe parents: 3426 diff changeset	54 if (nargin != 1 && nargin != 2)
6046 34f96dd5441b [project @ 2006-10-10 16:10:25 by jwe] jwe parents: 6024 diff changeset	55 print_usage ();
4852 404c7122853e [project @ 2004-04-06 17:23:37 by jwe] jwe parents: 3426 diff changeset	56 endif
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	57
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	58 if (!isnumeric (x))
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	59 error ("median: X must be a numeric vector or matrix");
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	60 endif
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	61
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	62 nd = ndims (x);
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	63 sz = size (x);
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	64 if (nargin != 2)
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	65 ## Find the first non-singleton dimension.
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	66 dim = find (sz > 1, 1);
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	67 if (isempty (dim))
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	68 dim = 1;
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	69 endif
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	70 else
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	71 if (!(isscalar (dim) && dim == fix (dim))
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	72 \|\| !(1 <= dim && dim <= nd))
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	73 error ("median: DIM must be an integer and a valid dimension");
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	74 endif
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	75 endif
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	76
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	77 if (numel (x) > 0)
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	78 n = size (x, dim);
9726 b7b89061bd0e reimplement median using nth_element Jaroslav Hajek <highegg@gmail.com> parents: 9211 diff changeset	79 k = floor ((n+1) / 2);
b7b89061bd0e reimplement median using nth_element Jaroslav Hajek <highegg@gmail.com> parents: 9211 diff changeset	80 if (mod (n, 2) == 1)
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	81 retval = nth_element (x, k, dim);
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	82 else
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	83 retval = mean (nth_element (x, k:k+1, dim), dim);
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	84 endif
10655 9e4407c19e8d make median more Matlab compatible (bug #29930) Jaroslav Hajek <highegg@gmail.com> parents: 9726 diff changeset	85 ## Inject NaNs where needed, to be consistent with Matlab.
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	86 retval(any (isnan (x), dim)) = NaN;
3200 781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	87 else
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	88 error ("median: invalid matrix argument");
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	89 endif
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	90
781c930425fd [project @ 1998-10-29 05:23:08 by jwe] jwe parents: diff changeset	91 endfunction
7411 83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	92
83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	93 %!test
83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	94 %! x = [1, 2, 3, 4, 5, 6];
83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	95 %! x2 = x';
83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	96 %! y = [1, 2, 3, 4, 5, 6, 7];
83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	97 %! y2 = y';
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	98 %!
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	99 %! assert(median (x) == median (x2) && median (x) == 3.5);
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	100 %! assert(median (y) == median (y2) && median (y) == 4);
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	101 %! assert(median ([x2, 2*x2]) == [3.5, 7]);
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	102 %! assert(median ([y2, 3*y2]) == [4, 12]);
7411 83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	103
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	104 %!assert(median ([1,2,NaN;4,5,6;NaN,8,9]), [NaN, 5, NaN]);
11360 2b03258c240b median.m: Add NaN test case from bug #29930. Rik <octave@nomad.inbox5.com> parents: 10821 diff changeset	105
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	106 %% Test input validation
7411 83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	107 %!error median ();
83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	108 %!error median (1, 2, 3);
11436 e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	109 %!error median ({1:5});
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	110 %!error median (true(1,5));
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	111 %!error median (1, ones(2,2));
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	112 %!error median (1, 1.5);
e151e23f73bc Overhaul base statistics functions and documentation of same. Rik <octave@nomad.inbox5.com> parents: 11360 diff changeset	113 %!error median (1, 0);
7411 83a8781b529d [project @ 2008-01-22 21:52:25 by jwe] jwe parents: 7017 diff changeset	114

Mercurial > hg > octave-nkf

annotate scripts/statistics/base/median.m @ 12575:d0b799dafede