Mercurial > octave-nkf
annotate doc/interpreter/strings.txi @ 20628:3af34e1ef330
Preliminary inclusion of uixx objects properties in the manual (bug #46076)
* doc/interpreter/genpropdoc.m: add uixx objects to the list of supported graphics objects
* doc/interpreter/genpropdoc.m (get_doc): add uixx objects and their specific properties (currently empty documentation)
* doc/interpreter/plot.txi("Interacting with Plots"): add a note and a reference about ui* family of functions.
* doc/interpreter/plot.txi("Interacting with Plots"): for consistency, remove "uimenu" reference. All the other uixx are already in the gui section
* doc/interpreter/plot.txi("graphics data structure"): add uixx objects
* doc/interpreter/gui.txi("UI Elements"): add "uimenu" function reference
* doc/module.mk: add rules to build uixx properties texi files.
* graphics.in.h: make uixx "__object__" property (Octave internal) hidden so that it does not appear in the documentation.
author | Pantxo Diribarne <pantxo.diribarne@gmail.com> |
---|---|
date | Fri, 09 Oct 2015 16:25:27 +0200 |
parents | 55c2d33e6773 |
children |
rev | line source |
---|---|
19731
4197fc428c7d
maint: Update copyright notices for 2015.
John W. Eaton <jwe@octave.org>
parents:
19630
diff
changeset
|
1 @c Copyright (C) 1996-2015 John W. Eaton |
7018 | 2 @c |
3 @c This file is part of Octave. | |
4 @c | |
5 @c Octave is free software; you can redistribute it and/or modify it | |
6 @c under the terms of the GNU General Public License as published by the | |
7 @c Free Software Foundation; either version 3 of the License, or (at | |
8 @c your option) any later version. | |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
9 @c |
7018 | 10 @c Octave is distributed in the hope that it will be useful, but WITHOUT |
11 @c ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
12 @c FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
13 @c for more details. | |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
14 @c |
7018 | 15 @c You should have received a copy of the GNU General Public License |
16 @c along with Octave; see the file COPYING. If not, see | |
17 @c <http://www.gnu.org/licenses/>. | |
3294 | 18 |
4167 | 19 @node Strings |
3294 | 20 @chapter Strings |
21 @cindex strings | |
22 @cindex character strings | |
23 @opindex " | |
24 @opindex ' | |
25 | |
26 A @dfn{string constant} consists of a sequence of characters enclosed in | |
27 either double-quote or single-quote marks. For example, both of the | |
28 following expressions | |
29 | |
30 @example | |
31 @group | |
32 "parrot" | |
33 'parrot' | |
34 @end group | |
35 @end example | |
36 | |
37 @noindent | |
38 represent the string whose contents are @samp{parrot}. Strings in | |
39 Octave can be of any length. | |
40 | |
41 Since the single-quote mark is also used for the transpose operator | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
42 (@pxref{Arithmetic Ops}) but double-quote marks have no other purpose in Octave, |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
43 it is best to use double-quote marks to denote strings. |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
44 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
45 Strings can be concatenated using the notation for defining matrices. For |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
46 example, the expression |
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
47 |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
48 @example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
49 [ "foo" , "bar" , "baz" ] |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
50 @end example |
3294 | 51 |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
52 @noindent |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
53 produces the string whose contents are @samp{foobarbaz}. @xref{Numeric Data |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
54 Types}, for more information about creating matrices. |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
55 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
56 @menu |
11255
d682cd6669ac
Update info-based documentation menus to include new nodes.
Rik <octave@nomad.inbox5.com>
parents:
11143
diff
changeset
|
57 * Escape Sequences in String Constants:: |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
58 * Character Arrays:: |
17152
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
59 * Creating Strings:: |
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
60 * Comparing Strings:: |
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
61 * Manipulating Strings:: |
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
62 * String Conversions:: |
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
63 * Character Class Functions:: |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
64 @end menu |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
65 |
11257
8d4c57258523
fix some menu problems in the manual
John W. Eaton <jwe@octave.org>
parents:
11255
diff
changeset
|
66 @node Escape Sequences in String Constants |
8d4c57258523
fix some menu problems in the manual
John W. Eaton <jwe@octave.org>
parents:
11255
diff
changeset
|
67 @section Escape Sequences in String Constants |
6554 | 68 @cindex escape sequence notation |
69 In double-quoted strings, the backslash character is used to introduce | |
6623 | 70 @dfn{escape sequences} that represent other characters. For example, |
6554 | 71 @samp{\n} embeds a newline character in a double-quoted string and |
14528
c67822beb7a4
maint: Backed out changeset 8c988dabbe8e
Rik <octave@nomad.inbox5.com>
parents:
14527
diff
changeset
|
72 @samp{\"} embeds a double quote character. In single-quoted strings, backslash |
c67822beb7a4
maint: Backed out changeset 8c988dabbe8e
Rik <octave@nomad.inbox5.com>
parents:
14527
diff
changeset
|
73 is not a special character. Here is an example showing the difference: |
3294 | 74 |
6554 | 75 @example |
6556 | 76 @group |
6554 | 77 toascii ("\n") |
6570 | 78 @result{} 10 |
6554 | 79 toascii ('\n') |
6570 | 80 @result{} [ 92 110 ] |
6556 | 81 @end group |
6554 | 82 @end example |
3294 | 83 |
14528
c67822beb7a4
maint: Backed out changeset 8c988dabbe8e
Rik <octave@nomad.inbox5.com>
parents:
14527
diff
changeset
|
84 Here is a table of all the escape sequences used in Octave (within |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
85 double quoted strings). They are the same as those used in the C |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
86 programming language. |
3294 | 87 |
88 @table @code | |
89 @item \\ | |
90 Represents a literal backslash, @samp{\}. | |
91 | |
92 @item \" | |
93 Represents a literal double-quote character, @samp{"}. | |
94 | |
95 @item \' | |
96 Represents a literal single-quote character, @samp{'}. | |
97 | |
3893 | 98 @item \0 |
16826
a4969508008e
doc: Periodic spellcheck of the documentation.
Rik <rik@octave.org>
parents:
16772
diff
changeset
|
99 Represents the null character, control-@@, ASCII code 0. |
3893 | 100 |
3294 | 101 @item \a |
102 Represents the ``alert'' character, control-g, ASCII code 7. | |
103 | |
104 @item \b | |
105 Represents a backspace, control-h, ASCII code 8. | |
106 | |
107 @item \f | |
108 Represents a formfeed, control-l, ASCII code 12. | |
109 | |
110 @item \n | |
111 Represents a newline, control-j, ASCII code 10. | |
112 | |
113 @item \r | |
114 Represents a carriage return, control-m, ASCII code 13. | |
115 | |
116 @item \t | |
117 Represents a horizontal tab, control-i, ASCII code 9. | |
118 | |
119 @item \v | |
120 Represents a vertical tab, control-k, ASCII code 11. | |
121 | |
17244
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
122 @item \@var{nnn} |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
123 Represents the octal value @var{nnn}, where @var{nnn} are one to three |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
124 digits between 0 and 7. For example, the code for the ASCII ESC |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
125 (escape) character is @samp{\033}. |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
126 |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
127 @item \x@var{hh}@dots{} |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
128 Represents the hexadecimal value @var{hh}, where @var{hh} are hexadecimal |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
129 digits (@samp{0} through @samp{9} and either @samp{A} through @samp{F} or |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
130 @samp{a} through @samp{f}). Like the same construct in @sc{ansi} C, |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
131 the escape sequence continues until the first non-hexadecimal digit is seen. |
9de751a10910
Add support for hexadecimal escape sequences in double-quoted strings (bug #39775)
Mike Miller <mtmiller@ieee.org>
parents:
17152
diff
changeset
|
132 However, using more than two hexadecimal digits produces undefined results. |
3294 | 133 @end table |
134 | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
135 In a single-quoted string there is only one escape sequence: you may insert a |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
136 single quote character using two single quote characters in succession. For |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
137 example, |
3294 | 138 |
139 @example | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
140 @group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
141 'I can''t escape' |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
142 @result{} I can't escape |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
143 @end group |
3294 | 144 @end example |
145 | |
14528
c67822beb7a4
maint: Backed out changeset 8c988dabbe8e
Rik <octave@nomad.inbox5.com>
parents:
14527
diff
changeset
|
146 In scripts the two different string types can be distinguished if necessary |
13943
5820f8ce683e
doc: Add undocumented functions to manual for 3.6.0 release
Rik <octave@nomad.inbox5.com>
parents:
12581
diff
changeset
|
147 by using @code{is_dq_string} and @code{is_sq_string}. |
5820f8ce683e
doc: Add undocumented functions to manual for 3.6.0 release
Rik <octave@nomad.inbox5.com>
parents:
12581
diff
changeset
|
148 |
5820f8ce683e
doc: Add undocumented functions to manual for 3.6.0 release
Rik <octave@nomad.inbox5.com>
parents:
12581
diff
changeset
|
149 @DOCSTRING(is_dq_string) |
5820f8ce683e
doc: Add undocumented functions to manual for 3.6.0 release
Rik <octave@nomad.inbox5.com>
parents:
12581
diff
changeset
|
150 |
5820f8ce683e
doc: Add undocumented functions to manual for 3.6.0 release
Rik <octave@nomad.inbox5.com>
parents:
12581
diff
changeset
|
151 @DOCSTRING(is_sq_string) |
3294 | 152 |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
153 @node Character Arrays |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
154 @section Character Arrays |
3294 | 155 |
6623 | 156 The string representation used by Octave is an array of characters, so |
17281
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
157 internally the string @nospell{@qcode{"dddddddddd"}} is actually a row vector |
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
158 of length 10 containing the value 100 in all places (100 is the ASCII code of |
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
159 @qcode{"d"}). This lends itself to the obvious generalization to character |
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
160 matrices. Using a matrix of characters, it is possible to represent a |
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
161 collection of same-length strings in one variable. The convention used in |
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
162 Octave is that each row in a character matrix is a separate string, but letting |
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
163 each column represent a string is equally possible. |
6623 | 164 |
165 The easiest way to create a character matrix is to put several strings | |
166 together into a matrix. | |
167 | |
168 @example | |
169 collection = [ "String #1"; "String #2" ]; | |
170 @end example | |
171 | |
172 @noindent | |
173 This creates a 2-by-9 character matrix. | |
174 | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
175 The function @code{ischar} can be used to test if an object is a character |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
176 matrix. |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
177 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
178 @DOCSTRING(ischar) |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
179 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
180 To test if an object is a string (i.e., a character vector and not a character |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
181 matrix) you can use the @code{ischar} function in combination with the |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
182 @code{isvector} function as in the following example: |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
183 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
184 @example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
185 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
186 ischar (collection) |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
187 @result{} 1 |
8442
502e58a0d44f
Fix docstrings, add examples, references and tests to string functions
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8372
diff
changeset
|
188 |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
189 ischar (collection) && isvector (collection) |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
190 @result{} 0 |
8442
502e58a0d44f
Fix docstrings, add examples, references and tests to string functions
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8372
diff
changeset
|
191 |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
192 ischar ("my string") && isvector ("my string") |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
193 @result{} 1 |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
194 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
195 @end example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
196 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
197 One relevant question is, what happens when a character matrix is |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
198 created from strings of different length. The answer is that Octave |
6623 | 199 puts blank characters at the end of strings shorter than the longest |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
200 string. It is possible to use a different character than the |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
201 blank character using the @code{string_fill_char} function. |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
202 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
203 @DOCSTRING(string_fill_char) |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
204 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
205 This shows a problem with character matrices. It simply isn't possible to |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
206 represent strings of different lengths. The solution is to use a cell array of |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
207 strings, which is described in @ref{Cell Arrays of Strings}. |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
208 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
209 @node Creating Strings |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
210 @section Creating Strings |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
211 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
212 The easiest way to create a string is, as illustrated in the introduction, |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
213 to enclose a text in double-quotes or single-quotes. It is however |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
214 possible to create a string without actually writing a text. The |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
215 function @code{blanks} creates a string of a given length consisting |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
216 only of blank characters (ASCII code 32). |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
217 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
218 @DOCSTRING(blanks) |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
219 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
220 @menu |
17152
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
221 * Concatenating Strings:: |
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
222 * Converting Numerical Data to Strings:: |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
223 @end menu |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
224 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
225 @node Concatenating Strings |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
226 @subsection Concatenating Strings |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
227 |
16994
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
228 Strings can be concatenated using matrix notation |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
229 (@pxref{Strings}, @ref{Character Arrays}) which is often the most natural |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
230 method. For example: |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
231 |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
232 @example |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
233 @group |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
234 fullname = [fname ".txt"]; |
17003
c6a39f7f193d
doc: Use '@@' to produce '@' in strings.txi
Rik <rik@octave.org>
parents:
16994
diff
changeset
|
235 email = ["<" user "@@" domain ">"]; |
16994
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
236 @end group |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
237 @end example |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
238 |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
239 @noindent |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
240 In each case it is easy to see what the final string will look like. This |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
241 method is also the most efficient. When using matrix concatenation the parser |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
242 immediately begins joining the strings without having to process |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
243 the overhead of a function call and the input validation of the associated |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
244 function. |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
245 |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
246 Nevertheless, there are several other functions for concatenating string |
333243133364
Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance.
Rik <rik@octave.org>
parents:
16826
diff
changeset
|
247 objects which can be useful in specific circumstances: @code{char}, |
17097
e7a059a9a644
doc: Use XREF as anchor prefix in documentation for clearer results in Info viewer.
Rik <rik@octave.org>
parents:
17003
diff
changeset
|
248 @code{strvcat}, @code{strcat}, and @code{cstrcat}. Finally, the general |
e7a059a9a644
doc: Use XREF as anchor prefix in documentation for clearer results in Info viewer.
Rik <rik@octave.org>
parents:
17003
diff
changeset
|
249 purpose concatenation functions can be used: see @ref{XREFcat,,cat}, |
e7a059a9a644
doc: Use XREF as anchor prefix in documentation for clearer results in Info viewer.
Rik <rik@octave.org>
parents:
17003
diff
changeset
|
250 @ref{XREFhorzcat,,horzcat}, and @ref{XREFvertcat,,vertcat}. |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
251 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
252 @itemize @bullet |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
253 @item All string concatenation functions except @code{cstrcat} |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
254 convert numerical input into character data by taking the corresponding ASCII |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
255 character for each element, as in the following example: |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
256 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
257 @example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
258 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
259 char ([98, 97, 110, 97, 110, 97]) |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
260 @result{} banana |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
261 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
262 @end example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
263 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
264 @item |
8372
8dff9cba15fe
move str2mat to deprecated and make it a simple wrapper around char
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8351
diff
changeset
|
265 @code{char} and @code{strvcat} |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
266 concatenate vertically, while @code{strcat} and @code{cstrcat} concatenate |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
267 horizontally. For example: |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
268 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
269 @example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
270 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
271 char ("an apple", "two pears") |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
272 @result{} an apple |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
273 two pears |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
274 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
275 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
276 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
277 strcat ("oc", "tave", " is", " good", " for you") |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
278 @result{} octave is good for you |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
279 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
280 @end example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
281 |
8372
8dff9cba15fe
move str2mat to deprecated and make it a simple wrapper around char
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8351
diff
changeset
|
282 @item @code{char} generates an empty row in the output |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
283 for each empty string in the input. @code{strvcat}, on the other hand, |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
284 eliminates empty strings. |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
285 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
286 @example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
287 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
288 char ("orange", "green", "", "red") |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
289 @result{} orange |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
290 green |
17281
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
291 |
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
292 red |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
293 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
294 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
295 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
296 strvcat ("orange", "green", "", "red") |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
297 @result{} orange |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
298 green |
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
299 red |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
300 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
301 @end example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
302 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
303 @item All string concatenation functions except @code{cstrcat} also accept cell |
8372
8dff9cba15fe
move str2mat to deprecated and make it a simple wrapper around char
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8351
diff
changeset
|
304 array data (@pxref{Cell Arrays}). @code{char} and |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
305 @code{strvcat} convert cell arrays into character arrays, while @code{strcat} |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
306 concatenates within the cells of the cell arrays: |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
307 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
308 @example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
309 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
310 char (@{"red", "green", "", "blue"@}) |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
311 @result{} red |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
312 green |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
313 |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
314 blue |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
315 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
316 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
317 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
318 strcat (@{"abc"; "ghi"@}, @{"def"; "jkl"@}) |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
319 @result{} |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
320 @{ |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
321 [1,1] = abcdef |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
322 [2,1] = ghijkl |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
323 @} |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
324 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
325 @end example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
326 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
327 @item @code{strcat} removes trailing white space in the arguments (except |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
328 within cell arrays), while @code{cstrcat} leaves white space untouched. Both |
9036
58604c45ca74
Cleanup of data types related documentation
Rik <rdrider0-list@yahoo.com>
parents:
8920
diff
changeset
|
329 kinds of behavior can be useful as can be seen in the examples: |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
330 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
331 @example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
332 @group |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
333 strcat (["dir1";"directory2"], ["/";"/"], ["file1";"file2"]) |
17281
bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Rik <rik@octave.org>
parents:
17244
diff
changeset
|
334 @result{} dir1/file1 |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
335 directory2/file2 |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
336 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
337 @group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
338 |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
339 cstrcat (["thirteen apples"; "a banana"], [" 5$";" 1$"]) |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
340 @result{} thirteen apples 5$ |
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
341 a banana 1$ |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
342 @end group |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
343 @end example |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
344 |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
345 Note that in the above example for @code{cstrcat}, the white space originates |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
346 from the internal representation of the strings in a string array |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
347 (@pxref{Character Arrays}). |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
348 @end itemize |
6623 | 349 |
4358 | 350 @DOCSTRING(char) |
351 | |
6502 | 352 @DOCSTRING(strvcat) |
353 | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
354 @DOCSTRING(strcat) |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
355 |
8286
6f2d95255911
fix @seealso references to point to existing anchors
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
7984
diff
changeset
|
356 @DOCSTRING(cstrcat) |
6f2d95255911
fix @seealso references to point to existing anchors
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
7984
diff
changeset
|
357 |
17152
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
358 @node Converting Numerical Data to Strings |
f2a8592b8fbd
doc: Shorten some long subsection names in Manual.
Rik <rik@octave.org>
parents:
17097
diff
changeset
|
359 @subsection Converting Numerical Data to Strings |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
360 Apart from the string concatenation functions (@pxref{Concatenating Strings}) |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
361 which cast numerical data to the corresponding ASCII characters, there are |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
362 several functions that format numerical data as strings. @code{mat2str} and |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
363 @code{num2str} convert real or complex matrices, while @code{int2str} converts |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
364 integer matrices. @code{int2str} takes the real part of complex values and |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
365 round fractional values to integer. A more flexible way to format numerical |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
366 data as strings is the @code{sprintf} function (@pxref{Formatted Output}, |
17097
e7a059a9a644
doc: Use XREF as anchor prefix in documentation for clearer results in Info viewer.
Rik <rik@octave.org>
parents:
17003
diff
changeset
|
367 @ref{XREFsprintf,,sprintf}). |
4535 | 368 |
6502 | 369 @DOCSTRING(mat2str) |
370 | |
371 @DOCSTRING(num2str) | |
3294 | 372 |
6623 | 373 @DOCSTRING(int2str) |
374 | |
375 @node Comparing Strings | |
376 @section Comparing Strings | |
377 | |
8828 | 378 Since a string is a character array, comparisons between strings work |
379 element by element as the following example shows: | |
6623 | 380 |
381 @example | |
9209
923c7cb7f13f
Simplify TeXinfo files by eliminating redundant @iftex followed by @tex construction.
Rik <rdrider0-list@yahoo.com>
parents:
9036
diff
changeset
|
382 @group |
6623 | 383 GNU = "GNU's Not UNIX"; |
384 spaces = (GNU == " ") | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
385 @result{} spaces = |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
386 0 0 0 0 0 1 0 0 0 1 0 0 0 0 |
9209
923c7cb7f13f
Simplify TeXinfo files by eliminating redundant @iftex followed by @tex construction.
Rik <rdrider0-list@yahoo.com>
parents:
9036
diff
changeset
|
387 @end group |
6623 | 388 @end example |
389 | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
390 @noindent To determine if two strings are identical it is necessary to use the |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
391 @code{strcmp} function. It compares complete strings and is case |
9036
58604c45ca74
Cleanup of data types related documentation
Rik <rdrider0-list@yahoo.com>
parents:
8920
diff
changeset
|
392 sensitive. @code{strncmp} compares only the first @code{N} characters (with |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
393 @code{N} given as a parameter). @code{strcmpi} and @code{strncmpi} are the |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
394 corresponding functions for case-insensitive comparison. |
6623 | 395 |
396 @DOCSTRING(strcmp) | |
397 | |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
398 @DOCSTRING(strncmp) |
6623 | 399 |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
400 @DOCSTRING(strcmpi) |
6623 | 401 |
402 @DOCSTRING(strncmpi) | |
403 | |
404 @node Manipulating Strings | |
405 @section Manipulating Strings | |
406 | |
407 Octave supports a wide range of functions for manipulating strings. | |
408 Since a string is just a matrix, simple manipulations can be accomplished | |
9036
58604c45ca74
Cleanup of data types related documentation
Rik <rdrider0-list@yahoo.com>
parents:
8920
diff
changeset
|
409 using standard operators. The following example shows how to replace |
6623 | 410 all blank characters with underscores. |
411 | |
412 @example | |
9036
58604c45ca74
Cleanup of data types related documentation
Rik <rdrider0-list@yahoo.com>
parents:
8920
diff
changeset
|
413 @group |
9209
923c7cb7f13f
Simplify TeXinfo files by eliminating redundant @iftex followed by @tex construction.
Rik <rdrider0-list@yahoo.com>
parents:
9036
diff
changeset
|
414 quote = ... |
7081 | 415 "First things first, but not necessarily in that order"; |
6623 | 416 quote( quote == " " ) = "_" |
19627
446c46af4b42
strip trailing whitespace from most source files
John W. Eaton <jwe@octave.org>
parents:
17744
diff
changeset
|
417 @result{} quote = |
7081 | 418 First_things_first,_but_not_necessarily_in_that_order |
9036
58604c45ca74
Cleanup of data types related documentation
Rik <rdrider0-list@yahoo.com>
parents:
8920
diff
changeset
|
419 @end group |
6623 | 420 @end example |
421 | |
422 For more complex manipulations, such as searching, replacing, and | |
7001 | 423 general regular expressions, the following functions come with Octave. |
3294 | 424 |
3361 | 425 @DOCSTRING(deblank) |
3294 | 426 |
8817
03b7f618ab3d
include docstrings for new functions in the manual
John W. Eaton <jwe@octave.org>
parents:
8442
diff
changeset
|
427 @DOCSTRING(strtrim) |
03b7f618ab3d
include docstrings for new functions in the manual
John W. Eaton <jwe@octave.org>
parents:
8442
diff
changeset
|
428 |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
429 @DOCSTRING(strtrunc) |
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
430 |
3361 | 431 @DOCSTRING(findstr) |
3294 | 432 |
8817
03b7f618ab3d
include docstrings for new functions in the manual
John W. Eaton <jwe@octave.org>
parents:
8442
diff
changeset
|
433 @DOCSTRING(strchr) |
03b7f618ab3d
include docstrings for new functions in the manual
John W. Eaton <jwe@octave.org>
parents:
8442
diff
changeset
|
434 |
3361 | 435 @DOCSTRING(index) |
3294 | 436 |
3361 | 437 @DOCSTRING(rindex) |
3294 | 438 |
6502 | 439 @DOCSTRING(strfind) |
440 | |
16408 | 441 @DOCSTRING(strjoin) |
442 | |
19991
55c2d33e6773
restore strmatch function; backout changeset edf5d63c82e1
John W. Eaton <jwe@octave.org>
parents:
19731
diff
changeset
|
443 @DOCSTRING(strmatch) |
55c2d33e6773
restore strmatch function; backout changeset edf5d63c82e1
John W. Eaton <jwe@octave.org>
parents:
19731
diff
changeset
|
444 |
6502 | 445 @DOCSTRING(strtok) |
446 | |
8879
1beaaffb3c1f
document strsplit, not split
John W. Eaton <jwe@octave.org>
parents:
8828
diff
changeset
|
447 @DOCSTRING(strsplit) |
3294 | 448 |
16725
57bf164f1608
Add ostrsplit() to the manual.
Ben Abbott <bpabbott@mac.com>
parents:
16408
diff
changeset
|
449 @DOCSTRING(ostrsplit) |
57bf164f1608
Add ostrsplit() to the manual.
Ben Abbott <bpabbott@mac.com>
parents:
16408
diff
changeset
|
450 |
11143
195cffc2d0a3
strings.txi: @DOCSTRING additions.
Ben Abbott <bpabbott@mac.com>
parents:
11103
diff
changeset
|
451 @DOCSTRING(strread) |
195cffc2d0a3
strings.txi: @DOCSTRING additions.
Ben Abbott <bpabbott@mac.com>
parents:
11103
diff
changeset
|
452 |
3361 | 453 @DOCSTRING(strrep) |
3294 | 454 |
3361 | 455 @DOCSTRING(substr) |
3294 | 456 |
5582 | 457 @DOCSTRING(regexp) |
458 | |
459 @DOCSTRING(regexpi) | |
460 | |
6549 | 461 @DOCSTRING(regexprep) |
462 | |
7984
bbaa5d7d0143
Some documentation updates
David Bateman <dbateman@free.fr>
parents:
7639
diff
changeset
|
463 @DOCSTRING(regexptranslate) |
bbaa5d7d0143
Some documentation updates
David Bateman <dbateman@free.fr>
parents:
7639
diff
changeset
|
464 |
11103
d4fc294a19e4
include untabify docstring in the manual
John W. Eaton <jwe@octave.org>
parents:
10828
diff
changeset
|
465 @DOCSTRING(untabify) |
d4fc294a19e4
include untabify docstring in the manual
John W. Eaton <jwe@octave.org>
parents:
10828
diff
changeset
|
466 |
4167 | 467 @node String Conversions |
3294 | 468 @section String Conversions |
469 | |
6623 | 470 Octave supports various kinds of conversions between strings and |
8351
4d78baf20ded
improve string documentation
Thorsten Meyer <thorsten.meyier@gmx.de>
parents:
8347
diff
changeset
|
471 numbers. As an example, it is possible to convert a string containing |
6623 | 472 a hexadecimal number to a floating point number. |
473 | |
474 @example | |
9209
923c7cb7f13f
Simplify TeXinfo files by eliminating redundant @iftex followed by @tex construction.
Rik <rdrider0-list@yahoo.com>
parents:
9036
diff
changeset
|
475 @group |
6623 | 476 hex2dec ("FF") |
14402
cbcaf5602469
doc: Make spacing nicer for Strings chapter of manual.
Rik <octave@nomad.inbox5.com>
parents:
14138
diff
changeset
|
477 @result{} 255 |
9209
923c7cb7f13f
Simplify TeXinfo files by eliminating redundant @iftex followed by @tex construction.
Rik <rdrider0-list@yahoo.com>
parents:
9036
diff
changeset
|
478 @end group |
6623 | 479 @end example |
480 | |
3361 | 481 @DOCSTRING(bin2dec) |
3294 | 482 |
3361 | 483 @DOCSTRING(dec2bin) |
3294 | 484 |
3361 | 485 @DOCSTRING(dec2hex) |
3294 | 486 |
3361 | 487 @DOCSTRING(hex2dec) |
3294 | 488 |
3920 | 489 @DOCSTRING(dec2base) |
490 | |
491 @DOCSTRING(base2dec) | |
492 | |
7639
b2fbb393a072
Add the num2hex and hex2num functions
David Bateman <dbateman@free.fr>
parents:
7081
diff
changeset
|
493 @DOCSTRING(num2hex) |
b2fbb393a072
Add the num2hex and hex2num functions
David Bateman <dbateman@free.fr>
parents:
7081
diff
changeset
|
494 |
b2fbb393a072
Add the num2hex and hex2num functions
David Bateman <dbateman@free.fr>
parents:
7081
diff
changeset
|
495 @DOCSTRING(hex2num) |
b2fbb393a072
Add the num2hex and hex2num functions
David Bateman <dbateman@free.fr>
parents:
7081
diff
changeset
|
496 |
6623 | 497 @DOCSTRING(str2double) |
3920 | 498 |
6623 | 499 @DOCSTRING(strjust) |
6502 | 500 |
3361 | 501 @DOCSTRING(str2num) |
3294 | 502 |
3361 | 503 @DOCSTRING(toascii) |
3294 | 504 |
3361 | 505 @DOCSTRING(tolower) |
3294 | 506 |
3361 | 507 @DOCSTRING(toupper) |
3294 | 508 |
3428 | 509 @DOCSTRING(do_string_escapes) |
510 | |
3361 | 511 @DOCSTRING(undo_string_escapes) |
3294 | 512 |
4167 | 513 @node Character Class Functions |
3294 | 514 @section Character Class Functions |
515 | |
516 Octave also provides the following character class test functions | |
517 patterned after the functions in the standard C library. They all | |
518 operate on string arrays and return matrices of zeros and ones. | |
519 Elements that are nonzero indicate that the condition was true for the | |
10828
322f43e0e170
Grammarcheck .txi documentation files.
Rik <octave@nomad.inbox5.com>
parents:
9209
diff
changeset
|
520 corresponding character in the string array. For example: |
3294 | 521 |
522 @example | |
523 @group | |
524 isalpha ("!Q@@WERT^Y&") | |
525 @result{} [ 0, 1, 0, 1, 1, 1, 1, 0, 1, 0 ] | |
526 @end group | |
527 @end example | |
528 | |
3361 | 529 @DOCSTRING(isalnum) |
3294 | 530 |
3361 | 531 @DOCSTRING(isalpha) |
532 | |
6549 | 533 @DOCSTRING(isletter) |
534 | |
3361 | 535 @DOCSTRING(islower) |
3294 | 536 |
12581
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
537 @DOCSTRING(isupper) |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
538 |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
539 @DOCSTRING(isdigit) |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
540 |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
541 @DOCSTRING(isxdigit) |
3294 | 542 |
3361 | 543 @DOCSTRING(ispunct) |
3294 | 544 |
3361 | 545 @DOCSTRING(isspace) |
3294 | 546 |
12581
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
547 @DOCSTRING(iscntrl) |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
548 |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
549 @DOCSTRING(isgraph) |
3294 | 550 |
12581
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
551 @DOCSTRING(isprint) |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
552 |
c8be316f9543
Group commonly used isXXX functions together in documentation.
Rik <octave@nomad.inbox5.com>
parents:
11523
diff
changeset
|
553 @DOCSTRING(isascii) |
7984
bbaa5d7d0143
Some documentation updates
David Bateman <dbateman@free.fr>
parents:
7639
diff
changeset
|
554 |
bbaa5d7d0143
Some documentation updates
David Bateman <dbateman@free.fr>
parents:
7639
diff
changeset
|
555 @DOCSTRING(isstrprop) |