|
2847
|
1 ## Copyright (C) 1996, 1997 John W. Eaton |
|
2313
|
2 ## |
|
|
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 |
|
|
7 ## the Free Software Foundation; either version 2, or (at your option) |
|
|
8 ## any later version. |
|
|
9 ## |
|
|
10 ## Octave is distributed in the hope that it will be useful, but |
|
|
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of |
|
|
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
|
|
13 ## General Public License for more details. |
|
|
14 ## |
|
|
15 ## You should have received a copy of the GNU General Public License |
|
|
16 ## along with Octave; see the file COPYING. If not, write to the Free |
|
|
17 ## Software Foundation, 59 Temple Place - Suite 330, Boston, MA |
|
|
18 ## 02111-1307, USA. |
|
245
|
19 |
|
2311
|
20 ## usage: rot90 (x, k) |
|
|
21 ## |
|
|
22 ## Rotate the matrix x counterclockwise k*90 degrees. |
|
|
23 ## |
|
|
24 ## If the second argument is omitted, k is taken to be 1. |
|
|
25 ## |
|
|
26 ## See also: flipud, fliplr |
|
4
|
27 |
|
2314
|
28 ## Author: jwe |
|
|
29 |
|
2311
|
30 function y = rot90 (x, k) |
|
4
|
31 |
|
|
32 if (nargin < 2) |
|
|
33 k = 1; |
|
|
34 endif |
|
|
35 |
|
|
36 if (imag (k) != 0 || fix (k) != k) |
|
|
37 error ("rot90: k must be an integer"); |
|
|
38 endif |
|
|
39 |
|
|
40 if (nargin == 1 || nargin == 2) |
|
|
41 k = rem (k, 4); |
|
|
42 if (k < 0) |
|
|
43 k = k + 4; |
|
|
44 endif |
|
|
45 if (k == 0) |
|
|
46 y = x; |
|
|
47 elseif (k == 1) |
|
3238
|
48 y = flipud (x.'); |
|
4
|
49 elseif (k == 2) |
|
|
50 y = flipud (fliplr (x)); |
|
|
51 elseif (k == 3) |
|
3238
|
52 y = (flipud (x)).'; |
|
4
|
53 else |
|
|
54 error ("rot90: internal error!"); |
|
|
55 endif |
|
|
56 else |
|
904
|
57 usage ("rot90 (x [, k])"); |
|
4
|
58 endif |
|
|
59 |
|
|
60 endfunction |
