Hi all, I hope it's not too trivial for the list - I'm trying to concatenate two factor arrays, and obtain the following:
> f1<-factor(c("a","a","b")) > f1 [1] a a b Levels: a b > f2<-factor(c("b","b","a")) > f2 [1] b b a Levels: a b > c(f1,f2) [1] 1 1 2 2 2 1 Instead of getting: [1] a a b b b a Levels: a b a related question is: how do I add a level which does not exists yet in a factored vector, so I'll be able to add later these values, without getting: In `[<-.factor`(`*tmp*`, 2, value = "c") : invalid factor level, NAs generated Thanks, EC ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.