Performs set union, intersection, (asymmetric!) difference, equality and membership on two vectors.
union(x, y)
intersect(x, y)
setdiff(x, y)
setequal(x, y)is.element(el, set)
vectors (of the same mode) containing a sequence of items (conceptually) with no duplicated values.
A vector of the same mode as x or y for
setdiff and intersect, respectively, and
of a common mode for union.
A logical scalar for setequal and a logical of the same
length as x for is.element.
Each of union, intersect, setdiff and
setequal will discard any duplicated values in the arguments,
and they apply as.vector to their arguments (and so
in particular coerce factors to character vectors).
is.element(x, y) is identical to x %in% y.
‘plotmath’ for the use of union and
intersect in plot annotation.
# NOT RUN {
(x <- c(sort(sample(1:20, 9)), NA))
(y <- c(sort(sample(3:23, 7)), NA))
union(x, y)
intersect(x, y)
setdiff(x, y)
setdiff(y, x)
setequal(x, y)
## True for all possible x & y :
setequal( union(x, y),
c(setdiff(x, y), intersect(x, y), setdiff(y, x)))
is.element(x, y) # length 10
is.element(y, x) # length 8
# }