TITLE(unique @@ Extract Unique Elements)
USAGE(
unique(x)
)
ALIAS(unique)
DESCRIPTION(
LANG(unique) returns a vector like LANG(x)
but with duplicate elements removed.
If an element is equal to one with a smaller index, it is removed.
)
SEEALSO(
LANG(LINK(duplicated)) which gives the indices of duplicated elements.
)
EXAMPLES(
unique(c(3:5, 11:8, 8 + 0:5))
length(unique(sample(100,100,replace=T)))# ~= 100(1 - 1/e) = 63.21
my.unique <- function(x) x[!duplicated(x)]
for(i in 1:4) { x <- rpois(100, pi); print(all(unique(x) == my.unique(x))) }
)
