Mercurial > hg > octave-nkf

annotate scripts/strings/strchr.m @ 14138:72c96de7a403 stable

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
maint: update copyright notices for 2012
author John W. Eaton <jwe@octave.org>
date Mon, 02 Jan 2012 14:25:41 -0500
parents 9da8fbd17b92
children 5d3a684236b0
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
14138
72c96de7a403 maint: update copyright notices for 2012
John W. Eaton <jwe@octave.org>
parents: 13320
diff changeset
1 ## Copyright (C) 2008-2012 Jaroslav Hajek
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
2 ##
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
3 ## This file is part of Octave.
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
4 ##
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
5 ## Octave is free software; you can redistribute it and/or modify it
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
6 ## under the terms of the GNU General Public License as published by
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
7 ## the Free Software Foundation; either version 3 of the License, or (at
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
8 ## your option) any later version.
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
9 ##
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
10 ## Octave is distributed in the hope that it will be useful, but
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
13 ## General Public License for more details.
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
14 ##
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
15 ## You should have received a copy of the GNU General Public License
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
16 ## along with Octave; see the file COPYING. If not, see
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
17 ## <http://www.gnu.org/licenses/>.
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
18
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
19 ## -*- texinfo -*-
10793
be55736a0783 Grammarcheck the documentation from m-files.
Rik <octave@nomad.inbox5.com>
parents: 10408
diff changeset
20 ## @deftypefn {Function File} {@var{idx} =} strchr (@var{str}, @var{chars})
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
21 ## @deftypefnx {Function File} {@var{idx} =} strchr (@var{str}, @var{chars}, @var{n})
8830
fa981a053064 doc fixes
John W. Eaton <jwe@octave.org>
parents: 8715
diff changeset
22 ## @deftypefnx {Function File} {@var{idx} =} strchr (@var{str}, @var{chars}, @var{n}, @var{direction})
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
23 ## @deftypefnx {Function File} {[@var{i}, @var{j}] =} strchr (@dots{})
11261
9c19b450b254 strchr.m: style fixes
John W. Eaton <jwe@octave.org>
parents: 11260
diff changeset
24 ## Search for the string @var{str} for occurrences of characters from
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
25 ## the set @var{chars}. The return value(s), as well as the @var{n} and
11261
9c19b450b254 strchr.m: style fixes
John W. Eaton <jwe@octave.org>
parents: 11260
diff changeset
26 ## @var{direction} arguments behave identically as in @code{find}.
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
27 ##
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
28 ## This will be faster than using regexp in most cases.
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
29 ##
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
30 ## @seealso{find}
8715
954b6f69f51d doc fixes
John W. Eaton <jwe@octave.org>
parents: 8552
diff changeset
31 ## @end deftypefn
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
32
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
33 function varargout = strchr (str, chars, varargin)
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
34
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
35 if (nargin < 2)
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
36 print_usage ();
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
37 elseif (! ischar (str))
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
38 error ("strchr: STR argument must be a string or string array");
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
39 elseif (! ischar (chars))
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
40 error ("strchr: CHARS argument must be a string");
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
41 endif
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
42
10408
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
43 if (isempty (chars))
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
44 mask = false (size (str));
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
45 elseif (length (chars) <= 4)
10408
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
46 ## With a few characters, it pays off to build the mask incrementally.
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
47 ## We do it via a for loop to save memory.
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
48 mask = str == chars(1);
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
49 for i = 2:length (chars)
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
50 mask |= str == chars(i);
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
51 endfor
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
52 else
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
53 ## Index the str into a mask of valid values.
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
54 ## This is slower than it could be because of the +1 issue.
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
55 f = false (256, 1);
12474
26d3164fd58d strchr.m: avoid implict string to number conversion
John W. Eaton <jwe@octave.org>
parents: 11587
diff changeset
56 f(uint8(chars)+1) = true;
11261
9c19b450b254 strchr.m: style fixes
John W. Eaton <jwe@octave.org>
parents: 11260
diff changeset
57 ## Default goes via double -- unnecessarily long.
9c19b450b254 strchr.m: style fixes
John W. Eaton <jwe@octave.org>
parents: 11260
diff changeset
58 si = uint32 (str);
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
59 ## in-place is faster than str+1
11261
9c19b450b254 strchr.m: style fixes
John W. Eaton <jwe@octave.org>
parents: 11260
diff changeset
60 ++si;
10408
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
61 mask = reshape (f(si), size (str));
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
62 endif
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
63
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
64 varargout = cell (1, nargout);
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
65 varargout{1} = [];
10408
a8869743d9fe optimize strchr
Jaroslav Hajek <highegg@gmail.com>
parents: 9036
diff changeset
66 [varargout{:}] = find (mask, varargin{:});
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
67
11587
c792872f8942 all script files: untabify and strip trailing whitespace
John W. Eaton <jwe@octave.org>
parents: 11523
diff changeset
68 endfunction
8552
3591fe09f3b1 add the strchr function
Jaroslav Hajek <highegg@gmail.com>
parents:
diff changeset
69
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
70
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
71 %!assert (strchr ("Octave is the best software", ""), zeros (1,0))
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
72 %!assert (strchr ("Octave is the best software", "best"), [3, 6, 9, 11, 13, 15, 16, 17, 18, 20, 23, 27])
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
73 %!assert (strchr ("Octave is the best software", "software"), [3, 4, 6, 9, 11, 13, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, 27])
11260
fd18ba11af57 Extra tests in strchr
Kim Hansen <kim@ange.dk>
parents: 10793
diff changeset
74
13320
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
75 %% Test input validation
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
76 %!error strchr ()
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
77 %!error strchr (1)
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
78 %!error <STR argument must be a string> strchr (1, "aeiou")
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
79 %!error <CHARS argument must be a string> strchr ("aeiou", 1)
9da8fbd17b92 strchr.m: Tune switching between algorithms. Add error messages to input validation.
Rik <octave@nomad.inbox5.com>
parents: 12474
diff changeset
80