length<-.factor
Set Length of a factor
Description
This function is an S3 method implementation of
the length<- generic for the factor class.
Usage
length(x) <- value
Arguments
| x |
a factor object.
|
| value |
an integer.
|
Value
returns an integer specifying the length of the
factor; that is, the number of its elements.
Details
When a value is assigned to the length of a factor object,
the factor object is shortened or lengthened
to the specified length. If the factor object is lengthened, missing values
are placed at the end of the resulting vector. Unlike
the default implementation of length, this method
retains the class and levels attribute of the factor object.
Examples
factorA <- factor(c("a", "b", "c"))
length(factorA) <- 5
factorA
# [1] a b c <NA> <NA>
# Levels: a b c
length(factorA)
# [1] 5
length(factorA) <- 1
factorA
# [1] a
# Levels: a b c
length(factorA)
# [1] 1