|
3200
|
1 ## Copyright (C) 1995, 1996, 1997 Kurt Hornik |
|
3426
|
2 ## |
|
3922
|
3 ## This file is part of Octave. |
|
|
4 ## |
|
|
5 ## Octave is free software; you can redistribute it and/or modify it |
|
|
6 ## under the terms of the GNU General Public License as published by |
|
3200
|
7 ## the Free Software Foundation; either version 2, or (at your option) |
|
|
8 ## any later version. |
|
3426
|
9 ## |
|
3922
|
10 ## Octave is distributed in the hope that it will be useful, but |
|
3200
|
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of |
|
|
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
|
3426
|
13 ## General Public License for more details. |
|
|
14 ## |
|
3200
|
15 ## You should have received a copy of the GNU General Public License |
|
3922
|
16 ## along with Octave; see the file COPYING. If not, write to the Free |
|
5307
|
17 ## Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
|
|
18 ## 02110-1301, USA. |
|
3200
|
19 |
|
3453
|
20 ## -*- texinfo -*- |
|
|
21 ## @deftypefn {Function File} {} center (@var{x}) |
|
4844
|
22 ## @deftypefnx {Function File} {} center (@var{x}, @var{dim}) |
|
3453
|
23 ## If @var{x} is a vector, subtract its mean. |
|
|
24 ## If @var{x} is a matrix, do the above for each column. |
|
4844
|
25 ## If the optional argument @var{dim} is given, perform the above |
|
|
26 ## operation along this dimension |
|
3453
|
27 ## @end deftypefn |
|
3200
|
28 |
|
5428
|
29 ## Author: KH <Kurt.Hornik@wu-wien.ac.at> |
|
3456
|
30 ## Description: Center by subtracting means |
|
3426
|
31 |
|
4844
|
32 function retval = center (x, varargin) |
|
3426
|
33 |
|
4844
|
34 if (nargin != 1 && nargin != 2) |
|
6046
|
35 print_usage (); |
|
3200
|
36 endif |
|
|
37 |
|
4030
|
38 if (isvector (x)) |
|
4844
|
39 retval = x - mean (x, varargin{:}); |
|
4030
|
40 elseif (ismatrix (x)) |
|
4844
|
41 if nargin < 2 |
|
6024
|
42 dim = find (size (x) > 1, 1); |
|
4844
|
43 if isempty (dim), |
|
|
44 dim=1; |
|
|
45 endif; |
|
|
46 else |
|
|
47 dim = varargin {1}; |
|
|
48 endif |
|
|
49 sz = ones (1, ndims (x)); |
|
|
50 sz (dim) = size (x, dim); |
|
|
51 retval = x - repmat (mean (x, dim), sz); |
|
3876
|
52 elseif (isempty (x)) |
|
|
53 retval = x; |
|
3200
|
54 else |
|
3458
|
55 error ("center: x must be a vector or a matrix"); |
|
3200
|
56 endif |
|
|
57 |
|
4844
|
58 endfunction |
