setops: Set operations

In olascodgreat/samife: A Grammar of Data Manipulation

Description

These functions override the set functions provided in base to make them generic so that efficient versions for data frames and other tables can be provided. The default methods call the base versions. Beware that intersect(), union() and setdiff() remove duplicates.

Usage

intersect(x, y, ...)

union(x, y, ...)

union_all(x, y, ...)

setdiff(x, y, ...)

setequal(x, y, ...)

Arguments

x, y	objects to perform set function on (ignoring order)
...	other arguments passed on to methods

Examples

mtcars$model <- rownames(mtcars)
first <- mtcars[1:20, ]
second <- mtcars[10:32, ]

intersect(first, second)
union(first, second)
setdiff(first, second)
setdiff(second, first)

union_all(first, second)
setequal(mtcars, mtcars[32:1, ])

# Handling of duplicates:
a <- data.frame(column = c(1:10, 10))
b <- data.frame(column = c(1:5, 5))

# intersection is 1 to 5, duplicates removed (5)
intersect(a, b)

# union is 1 to 10, duplicates removed (5 and 10)
union(a, b)

# set difference, duplicates removed (10)
setdiff(a, b)

# union all does not remove duplicates
union_all(a, b)

olascodgreat/samife documentation built on May 13, 2019, 6:11 p.m.