r - How to tell what is in one vector and not another?

Question

In matlab there is a way to find the values in one vector but not in the other.

for example:

x <- c(1,2,3,4)
y <- c(2,3,4)

is there any function that would tell me that the value in x that's not in y is 1?

Answer 1

you can use the setdiff() (set difference) function:

> setdiff(x, y)
[1] 1