Prune Factor Levels
Usage
pruneLevels(object)
Arguments
object
|
an object inheriting from class factor .
|
Description
The levels
attribute of object
are pruned to contain
only the levels occurring in the factor.Value
an object identical to object
, but with the levels
attribute containing only value occurring in the factor.Author(s)
Jose Pinheiro and Douglas BatesSee Also
factor
, link{ordered}
Examples
library(lme)
f1 <- factor(c(1,1,2,3,3,4,5))
levels(f1)
f2 <- f1[4:7]
levels(f2)
levels(pruneLevels(f2))