Check whether two vectors contain the same (unordered) elements in R

Question

I'd like to check whether two vectors contain the same elements, even if they're not ordered the same. For example, the function (let's call it SameElements) should satisfy these criteria:

SameElements(c(1, 2, 3), c(1, 2, 3))  # TRUE SameElements(c(1, 2, 3), c(3, 2, 1))  # TRUE SameElements(c(1, 2, 1), c(1, 2))  # FALSE SameElements(c(1, 1, 2, 3), c(3, 2, 1))  # FALSE 

Edit 1: Specified that function should return F when the vectors contain the same elements, but with different frequencies.

Edit 2: Cleaned up question to omit initial answer, as this is now in my actual answer.

Answer 1

I think you can use setequal(a,b)

Updated update setequal checks if two vectors are composed of the same elements but it does not check if these elements have the same occurrences in each vector.

Answer 2

In lieu of a cleaner alternative, here's the known solution:

SameElements <- function(a, b) return(identical(sort(a), sort(b))) SameElements(c(1, 2, 3), c(1, 3, 2))  # TRUE SameElements(c(1, 2, 3), c(1, 1, 3, 2))  # FALSE 

Edit: identical instead of all.equal(...) == T per nrussell's suggestion.