Finding elements that do not overlap between two vectors

Question

I\'m trying to identify elements which are not included in the other vector. For instance in two vectors I have

list.a <- c(\"James\", \"Mary\", \"Jack\",         


        

Answer 1

A nice one-liner that applies to duplicates:

anti_join(data_frame(c(1,1,2,2)), data_frame(c(1,1)))

This returns the data frame {2,2}. This however doesn't apply to the case of 1,2 in 1,1,2,2, because it finds it twice