Re: Dumbest Question of the New Year

["Richard M. Heiberger" <rmh@temple.edu>]

I think this is what you are looking for

tmp <- data.frame(aa=c("a","b","c","a","a"),
                  bb=c("d","e","f","e","f"),
                  cc=c("g","h","i","i","h"))
tmp$new <- interaction(tmp$aa, tmp$bb, tmp$cc)
tmp
levels(tmp$new)


If not, then please send the list a sample input and what you desire
as an output and someone will get back to you with an answer.

Rich