Skip to Content

character {base}

Character Vectors
R 3.0.2


Create or test for objects of type "character".


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


A non-negative integer specifying the desired length. Double values will be coerced to integer: supplying an argument of length other than one is an error.
object to be coerced or tested.
further arguments passed to or from other methods.


as.character and is.character are generic: you can write methods to handle specific classes of objects, see InternalMethods. Further, for as.character the default method calls as.vector, so dispatch is first on methods for as.character and then for methods for as.vector.

as.character represents real and complex numbers to 15 significant digits (technically the compiler's setting of the ISO C constant DBL_DIG, which will be 15 on machines supporting IEC60559 arithmetic according to the C99 standard). This ensures that all the digits in the result will be reliable (and not the result of representation error), but does mean that conversion to character and back to numeric may change the number. If you want to convert numbers to character with the maximum possible precision, use format.


character creates a character vector of the specified length. The elements of the vector are all equal to "".

as.character attempts to coerce its argument to character type; like as.vector it strips attributes including names. For lists it deparses the elements individually, except that it extracts the first element of length-one character vectors.

is.character returns TRUE or FALSE depending on whether its argument is of character type or not.


Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.


as.character breaks lines in language objects at 500 characters, and inserts newlines. Prior to 2.15.0 lines were truncated (at about 70 characters before 1.3.1).

See Also

paste, substr and strsplit for character concatenation and splitting, chartr for character translation and casefolding (e.g., upper to lower case) and sub, grep etc for string matching and substitutions. Note that = "character") gives even more links.

deparse, which is normally preferable to as.character for language objects.


form <- y ~ a + b + c
as.character(form)  ## length 3
deparse(form)       ## like the input
a0 <- 11/999          # has a repeating decimal representation
(a1 <- as.character(a0))
format(a0, digits = 16) # shows one more digit
a2 <- as.numeric(a1)
a2 - a0               # normally around -1e-17
as.character(a2)      # normally different from a1
print(c(a0, a2), digits = 16)

Documentation reproduced from R 3.0.2. License: GPL-2.