Atom - f - Filter (Include)

Characters: f

Tags: array

Arity: dyadic

This atom is dyadic, which means it takes two arguments.


Keep elements in x that are in y (remove elements in x that are not in y).


This also works as intersection if you don't have duplicate elements in the left argument or don't care about keeping them. If the counts of items in either argument matters, consider œ& (Multiset Intersection).