Prune Factor Levels

DESCRIPTION:

The levels attribute of object are pruned to contain only the levels occurring in the factor.

USAGE:

pruneLevels(object) 

REQUIRED ARGUMENTS:

object
an object inheriting from class factor.

VALUE:

an object identical to object, but with the levels attribute containing only value occurring in the factor.

SEE ALSO:

,

EXAMPLES:

f1 <- factor(c(1,1,2,3,3,4,5)) 
levels(f1) 
f2 <- f1[4:7] 
levels(f2) 
levels(pruneLevels(f2))