Calling setdiff() on multiple vectors

Question

How can I use setdiff() in R to get the elements that are in one vector but not in the others My example is as follows:

dat1 <- c("osa", "bli", "usd", "mnl")
dat2 <- c("mnu", "erd", "usd", "mnl")
dat3 <- c("ssu", "erd", "usd", "mnl")

The following code only returns what is diffrent in dat1 compared to dat2 and dat3:

diffs <- Reduce(setdiff, 
        list(A = dat1,
             B = dat2,
             C = dat3
)

How can I modify this code to be able to get all the elements that are uniquely present in on vector compared to the other? Thanks

Answer 1

another solution using setdiff :

myl <- list(A = dat1,
            B = dat2,
            C = dat3)
lapply(1:length(myl), function(n) setdiff(myl[[n]], unlist(myl[-n])))

[[1]]
[1] "osa" "bli"

[[2]]
[1] "mnu"

[[3]]
[1] "ssu"

Answer 2

a second possibility :

f <- function (...) 
{
  aux <- list(...)
  ind <- rep(1:length(aux), sapply(aux, length))
  x <- unlist(aux)
  boo <- !(duplicated(x) | duplicated(x, fromLast = T))
  split(x[boo], ind[boo])
}
f(dat1, dat2, dat3)
$`1`
[1] "osa" "bli"

$`2`
[1] "mnu"

$`3`
[1] "ssu"

Answer 3

Try this:

all.dat    <- list(dat1, dat2, dat3)
from.dat   <- rep(seq_along(all.dat), sapply(all.dat, length))
in.dat     <- split(from.dat, unlist(all.dat))
in.one.dat <- in.dat[sapply(in.dat, length) == 1]
in.one.dat
# $bli
# [1] 1

# $mnu
# [1] 2

# $osa
# [1] 1

# $ssu
# [1] 3

which tells you what items are found in only one of the dat objects, and which one. If you only care for the names, then finish with: names(in.one.dat).