levels() function for a vector
Karen levels returns the levels attribute of a variable, and a vector has no such attribute. This is usually used with a factor, e.g. > temp <- c(3, 5, 5, NA) > levels(factor(temp)) [1] "3" "5" Best wishes Richard
Chang Liu wrote:
Hello: I'm trying to use levels function, but I don't know why it's returning NULL. For example:
temp[1] 3 5 5 NA> levels(temp)NULL>
Also, I've tried:
list(temp)[[1]][1] "3" "5" "5" NA
levels(list(temp))NULL
Is there a specific requirement on the parameter? Karen
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