| levels.factor {base} | R Documentation |
levels<- provides a way to alter the levels attribute of factor.
value can be a vector of character strings with length at least the
the number of levels of x, or a named list specifying how to
rename the levels.
levels(x) <- value
factor, levels,
levels<-, nlevels.
# assign individual levels
x <- gl(2, 4, 8)
levels(x)[1] <- "low"
levels(x)[2] <- "high"
x
# or as a group
y <- gl(2, 4, 8)
levels(y) <- c("low", "high")
y
# combine some levels
z <- gl(3, 2, 12)
levels(z) <- c("A", "B", "A")
z
# same, using a named list
z <- gl(3, 2, 12)
levels(z) <- list(A=c(1,3), B=2)
z
# we can add levels this way:
f <- factor(c("a","b"))
levels(f) <- c("c", "a", "b")
f
f <- factor(c("a","b"))
levels(f) <- list(C="C", A="a", B="b")
f