1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
## Copyright (C) 1996 Kurt Hornik
##
## This file is part of Octave.
##
## Octave is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2, or (at your option)
## any later version.
##
## Octave is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
## General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with Octave; see the file COPYING. If not, write to the Free
## Software Foundation, 59 Temple Place - Suite 330, Boston, MA
## 02111-1307, USA.
## usage: substr (s, offset, len)
##
## Returns the substring of S of length LEN starting at index OFFSET.
## If OFFSET is negative, extraction starts that far from the end of
## the string. If LEN is omitted, the substring extends to the end
## of S.
## Author: Kurt Hornik <Kurt.Hornik@ci.tuwien.ac.at>
## Adapted-By: jwe
function t = substr (s, offset, len)
if (nargin < 2 || nargin > 3)
usage ("substr (s, offset [, len])");
endif
if (isstr (s))
nc = columns (s);
if (abs (offset) > 0 && abs (offset) <= nc)
if (offset > 0)
beg = offset;
else
beg = nc + offset + 1;
endif
if (nargin == 2)
eos = nc;
else
eos = beg + len - 1;
endif
if (eos <= nc)
t = s (:, beg:eos);
else
error ("substr: length = %d out of range", len);
endif
else
error ("substr: offset = %d out of range", offset);
endif
else
error ("substr: expecting string argument");
endif
endfunction
|
