How to exclude a level from a factor
Problem solved. Thanks a lot for your replies!
x
[1] a b c Levels: a b c
factor(as.character(x),exclude="c")
[1] a b <NA> Levels: a b "exclude=" option may not work on factors. One has to convert the factor to character first. Qiong
On Tue, 20 Sep 2005, Sundar Dorai-Raj wrote:
Qiong Yang wrote:
Hi, I could not use 'exlcude=' option in factor() to exclude a level from a existing factor. x is a factor:
x
[1] a b c Levels: a b c
factor(x,exclude="c")
[1] a b c Levels: a b c Warning message: NAs introduced by coercion However, "c" is not coded as NA. The following does not work either:
factor(x,exclude=factor("c",levels=c("a","b","c")))
[1] a b c Levels: a b c What's wrong with my codes?
I think you want: x <- factor(letters[1:3]) factor(as.character(x), exclude = "c") HTH, --sundar