How to convert factor levels to list, in R

r list dataframe r-factor
jpinelo picture jpinelo · May 9, 2015 · Viewed 27k times · Source

Imagine a data frame such as df1 below:

df1 <- data.frame(v1 = as.factor(c("m0p1", "m5p30", "m11p20", "m59p60", "m59p60")))

How do I create a list of all the levels of a variable? Thank you.

Answer

Phil picture Phil · May 9, 2015

To print the levels in the variable, use levels() as @scoa says:

levels(df1$v1)

To make it an explicit list use as.list() as well:

l <- as.list(levels(df1$v1))
l

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