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comparison scripts/strings/substr.m @ 2355:c9f70d39255f

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[project @ 1996-08-20 23:30:54 by jwe]
author jwe
date Tue, 20 Aug 1996 23:32:09 +0000
parents b5568c31ee2c
children 4f40efa995c1
comparison
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2354:2ce6e1ec9b53 2355:c9f70d39255f
15 ## You should have received a copy of the GNU General Public License 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 16 ## along with Octave; see the file COPYING. If not, write to the Free
17 ## Software Foundation, 59 Temple Place - Suite 330, Boston, MA 17 ## Software Foundation, 59 Temple Place - Suite 330, Boston, MA
18 ## 02111-1307, USA. 18 ## 02111-1307, USA.
19 19
20 ## usage: substr (s, beg, len) 20 ## usage: substr (s, offset, len)
21 ## 21 ##
22 ## Returns the substring of S of length LEN starting at index BEG. 22 ## Returns the substring of S of length LEN starting at index OFFSET.
23 ## If LEN is missing, the substring extends to the end of S. 23 ## If OFFSET is negative, extraction starts that far from the end of
24 ## the string. If LEN is omitted, the substring extends to the end
25 ## of S.
24 26
25 ## Author: jwe 27 ## Author: Kurt Hornik <Kurt.Hornik@ci.tuwien.ac.at>
28 ## Adapted-By: jwe
26 29
27 function t = substr (s, beg, len) 30 function t = substr (s, offset, len)
28
29 ## Original version by Kurt Hornik <Kurt.Hornik@ci.tuwien.ac.at>.
30 31
31 if (nargin < 2 || nargin > 3) 32 if (nargin < 2 || nargin > 3)
32 usage ("substr (s, beg, len)"); 33 usage ("substr (s, offset [, len])");
33 endif 34 endif
34 35
35 if (isstr (s)) 36 if (isstr (s))
36 nc = columns (s); 37 nc = columns (s);
37 if (beg > 0 && beg <= nc) 38 if (abs (offset) > 0 && abs (offset) <= nc)
39 if (offset > 0)
40 beg = offset;
41 else
42 beg = nc + offset + 1;
43 endif
38 if (nargin == 2) 44 if (nargin == 2)
39 eos = nc; 45 eos = nc;
40 else 46 else
41 eos = beg + len - 1; 47 eos = beg + len - 1;
42 endif 48 endif
44 t = s (:, beg:eos); 50 t = s (:, beg:eos);
45 else 51 else
46 error ("substr: length = %d out of range", len); 52 error ("substr: length = %d out of range", len);
47 endif 53 endif
48 else 54 else
49 error ("substr: beginning index = %d out of range", beg); 55 error ("substr: offset = %d out of range", offset);
50 endif 56 endif
51 else 57 else
52 error ("substr: expecting string argument"); 58 error ("substr: expecting string argument");
53 endif 59 endif
54 60