The cut() function converts numerical variables to factors. You can supply breaks to tell where the cuts should happen. This replaces your attempt at levels. Then you apply your labels. You also need to specify a right argument - should the interval be closed on the right (or left if false).
set.seed(10)
x <- sample(1:200, 1000, replace = TRUE)
summary(x)
Min. 1st Qu. Median Mean 3rd Qu. Max.
1.00 50.75 101.00 101.57 153.00 200.00
x <- cut(x, breaks = c(0, 10, 49, 200),
labels = c("small", "medium", "large"),
right = TRUE)
summary(x)
small medium large
51 189 760
I also want to point out an issue with your code. In your line labels = c("small"),c("medium"),c("large"), you have the commas outside the c(). You should enclose all desired elements of your vector in the same c():
labels = c("small", "medium", "large")
If the commas are outside of the parentheses, R will map only c("small") to labels and then try to match c("medium") to the next argument of the function.
