bit (version 4.6.0)

bit_sort_unique: bit sort unique

Description

fast combination of sort() and unique() for integers

Usage

bit_sort_unique(
  x,
  decreasing = FALSE,
  na.last = NA,
  has.dup = TRUE,
  range_na = NULL
)

Value

a sorted unique integer vector

Arguments

x

an integer vector

decreasing

FALSE (ascending) or TRUE (descending)

na.last

NA removes NAs, FALSE puts NAs at the beginning, TRUE puts NAs at the end

has.dup

TRUE (the default) assumes that x might have duplicates, set to FALSE if duplicates are impossible

range_na

NULL calls range_na(), optionally the result of range_na() can be given here to avoid calling it again

Details

determines the range of the integers and checks if the density justifies use of a bit vector; if yes, creates the result using a bit vector; if no, falls back to sort(unique())

See Also

sort(), unique(), bit_sort(), bit_unique()

Examples

bit_sort_unique(c(2L, 1L, NA, NA, 1L, 2L))
bit_sort_unique(c(2L, 1L, NA, NA, 1L, 2L), na.last=FALSE)
bit_sort_unique(c(2L, 1L, NA, NA, 1L, 2L), na.last=TRUE)
bit_sort_unique(c(2L, 1L, NA, NA, 1L, 2L), decreasing = TRUE)
bit_sort_unique(c(2L, 1L, NA, NA, 1L, 2L), decreasing = TRUE, na.last=FALSE)
bit_sort_unique(c(2L, 1L, NA, NA, 1L, 2L), decreasing = TRUE, na.last=TRUE)

if (FALSE) {
x <- sample(1e7, replace=TRUE)
system.time(bit_sort_unique(x))
system.time(sort(unique(x)))
x <- sample(1e7)
system.time(bit_sort_unique(x))
system.time(sort(x))
}