correction to the previously asked question (about merging factors)

     What about the following:

 > F1 <- factor(c("b", "a"))
 > F2 <- factor(c("c", "b"))
 > k1 <- length(F1)
 > k2 <- length(F2)
 > F12.lvls <- unique(c(levels(F1), levels(F2)))
 > F. <- factor(rep(F12.lvls[1], k1+k1), levels=F12.lvls)
 > F.[1:k1] <- F1
 > F.[-(1:k1)] <- F2
 > F.

[1] b a c b
Levels: a b c

     This saves converting the factors to characters, which might save 
computer time at the expense of your time.      hope this helps.      
spencer graves

Svetlana Eden wrote:

I have two factors l1, l2, and I'd like to merge them.

(Remark:       The factors can not be converted to charaters)

Function c() does not give me the result I want:


 

l1 = factor(c('aaaa', 'bbbb'))
l2 = factor(c('ccc', 'dd'))
lMerge = factor(c(l1, l2))
lMerge
  

[1] 1 2 1 2
Levels: 1 2
 

I'd like to merge l1 and l2 and to get lMerge 
----------------------------------------------

[1] aaaa bbbb ccc dd
Levels: aaaa bbbb ccc dd

instead of ----------

[1] 1 2 1 2
Levels: 1 2
 


How should I do that without converting the factors back to strings.
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