Answer to: Counting instances of genotype strings where order is irrelevant within locus

As @Rui Barradas mentioned, you could first make the sequence sorted and then apply table. My solution follows the same idea but use order + intToUtf8 + utf8ToInt to finish the sorting processes x <-c("AB", "Ab", "aB", "ab") y <-c("AB", "Ab", "aB", "ab") table(outer(x,y, Vectorize(\(p,q) {u <- paste0(p,q); intToUtf8(utf8ToInt(u)[order(utf8ToInt(u))])}))) and you will obtain aabb Aabb AAbb AABb AABB ABab ABBa Baab BBaa 1 2 1 2 1 4 2 2 1