character
Character Objects

### Description

Creates or tests for objects of mode character.

### Usage

    character(length = 0L)
    is.character(x)
    as.character(x, ...)

### Arguments

length | integer giving the length of the returned object.
... | additional arguments passed to the generic method.
x | any S object.

### Details

is.character is not generic.
as.character is generic and has a method implemented for class factor. The default method of as.character calls as.vector(x, mode="character"). Note that as.vector is generic.
Simple objects have no attributes. Data elements of objects of mode "character" are character strings. In most R expressions, it is not necessary to ensure explicitly that data are of a particular mode. For example, the function paste does not need character arguments; it coerces data to character as needed.
Note the difference between coercing to a simple object of mode "character" and setting the mode attribute:
mode(myobject) <- "character"
This example changes the mode of myobject but leaves all other attributes unchanged. (For example, a matrix stays a matrix.)
Note that the value of as.character(myobject) has no attributes.
If you use ascii codes in a character string, "\n" denotes an ascii newline character and "\t" denotes an ascii tab character. "\\" denotes a backslash, and "\"" represents a quote within a string. Some other C escape sequences are allowed but are not supported. Arbitrary ascii codes might be included by "\nnn", where nnn is a 3-digit number in octal notation (for example, "\012" denotes "\n").
Value

character | returns a character vector of the length specified containing null strings ("").

is.character | returns TRUE if x has mode "character". Otherwise, it returns FALSE. Its behavior is unaffected by any attributes of x. For example, this function returns TRUE if x is a character array (in contrast to the behavior of is.vector).

as.character | returns x if x is a simple object of mode "character". Otherwise, it returns a character vector of the same length as x, with data resulting from coercing the elements of x to mode "character".

See Also
paste, format, substring, deparse, nchar, mode.
Examples

    character(5)  #   a character object with length 5: "", "", "", "",""
    as.character(1:10)  #    character representations of 1,2,...,10
    x <- matrix(c("a","b","c","d"), 2)
    is.character(x)
    #  TRUE, since the mode of x is character though its class is matrix
    as.character(x)  #  "a","b","c","d"
    x <- factor(c("a","b","c","a"))   #  Examples for a factor
    is.character(x)  #  FALSE, since the mode of x is numeric for a factor
    as.character(x)  #  "a","b","c","a"
    x <- ordered(c("a","b","c","a"))   #  Examples for an ordered factor
    is.character(x)
    #  FALSE, since the mode of x is numeric for an ordered factor
    as.character(x)  #  "a","b","c","a"

Package base version 6.1.5-18
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