GNU Octave Manual Version 3 by John W. Eaton, David Bateman, Søren Hauberg Paperback (6"x9"), 568 pages ISBN 095461206X RRP £24.95 ($39.95) |
5 Strings
A string constant consists of a sequence of characters enclosed in either double-quote or single-quote marks. For example, both of the following expressions
"parrot" 'parrot'
represent the string whose contents are ‘parrot’. Strings in Octave can be of any length.
Since the single-quote mark is also used for the transpose operator (see section 8.3 Arithmetic Operators) but double-quote marks have no other purpose in Octave, it is best to use double-quote marks to denote strings.
In double-quoted strings, the backslash character is used to introduce escape sequences that represent other characters. For example, ‘\n’ embeds a newline character in a double-quoted string and ‘\"’ embeds a double quote character.
In single-quoted strings, backslash is not a special character.
Here is an example showing the difference
toascii ("\n") => 10 toascii ('\n') => [ 92 110 ]
You may also insert a single quote character in a single-quoted string by using two single quote characters in succession. For example,
'I can”t escape' => I can't escape
Here is a table of all the escape sequences used in Octave. They are the same as those used in the C programming language.
\\
- Represents a literal backslash, ‘\’.
\"
- Represents a literal double-quote character, ‘"’.
\'
- Represents a literal single-quote character, ‘'’.
\0
- Represents the “nul” character, control-@, ASCII code 0.
\a
- Represents the “alert” character, control-g, ASCII code 7.
\b
- Represents a backspace, control-h, ASCII code 8.
\f
- Represents a formfeed, control-l, ASCII code 12.
\n
- Represents a newline, control-j, ASCII code 10.
\r
- Represents a carriage return, control-m, ASCII code 13.
\t
- Represents a horizontal tab, control-i, ASCII code 9.
\v
- Represents a vertical tab, control-k, ASCII code 11.
Strings may be concatenated using the notation for defining matrices. For example, the expression
[ "foo" , "bar" , "baz" ]
produces the string whose contents are ‘foobarbaz’. See section 4 Numeric Data Types, for more information about creating matrices.
ISBN 095461206X | GNU Octave Manual Version 3 | See the print edition |