Julia equivalent to 'not in' in R

General Usage
1

What would be Julia code for the following R code:
a ← c(1:5)
b ← c(1:10)
c ← b[-a]

Thanks,

Patrik

2

I’m not an R expert, but you want the elements of b which are NOT part of a as well, right?

One way would be:

c = Iterators.filter(x -> x ∉ a, b) (on lastest master, if you’re on 0.5 it would be c = filter(x -> x ∉ a, b)).

3

Do you want setdiff(b, a) ?

4

I frequently use b[setdiff(1:end, a)].

3 Likes
5

Oh, has filter() left Base? Must remember that…

6

As far as I understand, no. But it has moved into a module called Iterators within Base.

1 Like
7

NamedArrays implements a Not method that does what the minus index does in R. I don’t know why a very common ideom like that is not in Julia Base though?

8

I made a PR for something like that in Base a long while back. Seems like a reasonable addition to me.

5 Likes
9

It’s funny to see that the branch is apparently still alive.

10

Thanks for your replies. setdiff() seems to be a work around, but that function is the same as %in% in R.