To check whether a value is a character use the is.character()
function. To coerce a variable to a character use the as.character()
function.
x <- "The quick brown fox jumps over the lazy dog"
class(x)
[1] "character"
is.character(x)
[1] TRUE
Note that numerics can be coerced to characters, but attempting to coerce a character to numeric may result in NA
.
as.numeric("2")
[1] 2
as.numeric("fox")
[1] NA
Warning message:
NAs introduced by coercion