factor level for non-existing value
Hi
Hello everybody!
Let's assume I have the following factor with it's levels:
a<-factor(c(2,3,3,2,4,2,3,2,2,2,3,2,3))
mydata<-data.frame(a)
When I plot the vector "a" using
barplot(table(mydata$a)
unfortunately the value "1" does not
show up, as it does not appear in my data.
But still, it theoretically exists.
How can I assign the following levels to the factor?
1: dislike very much
2: dislike
3: like
4: like very much
I have already tried the following code, which does not work
levels(data$a)<-c("dislike very much","dislike","like","like very much")
as "2" then becomes "dislike very much".
you can do it when constructing a factor
a<-factor(c(2,3,3,2,4,2,3,2,2,2,3,2,3), levels=1:4,labels=c("dislike very
much","dislike","like","like very much"))
or when you already have a factor
a<-factor(a, levels=1:4)
I basically understand that factor is a vector of numeric values with
levels and labels attribute. Each level can have some label which can be
changed independently. All levels does not need to be present in a factor.
However you shall not confuse it with function ?labels which has nothing
to do with factors.
Regards
Petr
I hope you understand my problem. Thank you for any help! [[alternative HTML version deleted]]
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