sets {base}R Documentation

Set Operations

Description

Performs set union, intersection, (asymmetric!) difference, equality and membership on two vectors.

Usage

union(x, y)
intersect(x, y)
setdiff(x, y)
setequal(x, y)
is.element(el, set)

Arguments

x, y, el, set vectors (of the same mode) containing a sequence of items (conceptually) with no duplicated values.

Details

Each of union, intersect and setdiff will remove any duplicated values in the arguments.

is.element(x, y) is identical to x %in% y.

Value

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.

See Also

%in%

Examples

(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

[Package base version 2.1.0 Index]