[R] levels of factor

[Luis Rideau Cruz]

R-help,

I have a data frame wich I subset like :

a <- subset(df,df$"column2" %in% c("factor1","factor2")  & df$"column2"==1)

But when I type levels(a$"column2") I still get the same levels as in df (my original data frame)

Why is that?
Is it right?

Luis

Luis Ridao Cruz
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