unique-set-speed-test.R

library(dplyr)

c_sort_collapse <- function(...){
  c(...) |> 
    sort() |> 
    paste(collapse = ".")
}

unique_set <- function(...){
  list(...) |> 
    purrr::pmap_chr(c_sort_collapse) |> 
    unique()
}


set.seed(123)
x <- sample(letters, 1000, replace = TRUE)

set.seed(12)
y <- sample(letters, 1000, replace = TRUE)

unique_set_matrix <- function(...){
  matrix(c(...), nrow = length(list(...)), byrow = TRUE) |>
    apply(2, sort) |>
    asplit(2) |>
    unique() |>
    sapply(paste, collapse = ".")
}

microbenchmark::microbenchmark(
  tidy = unique_set(x, y),
  matrix = unique_set_matrix(x, y),
  Map = Map(\(x,y) paste0(sort(c(x,y)) , collapse = ".") , x , y) |>
    unique() |> unlist(),
  times = 20
)
#> Unit: milliseconds
#>    expr     min      lq     mean   median       uq     max neval
#>    tidy 23.0659 24.4679 30.04869 28.94710 33.89015 47.0418    20
#>  matrix 23.1267 25.5710 29.10305 28.10055 31.65875 46.9684    20
#>     Map 21.9148 26.1991 28.88400 27.78860 29.78030 46.8089    20

See associated SO question: https://stackoverflow.com/questions/73243043/return-unique-combinations-of-items-r?noredirect=1#comment129367035_73243043 -- thus far seems like the best improvement comes from replacing sort() with stringi::stri_sort()