How do I filter a list in KDB?

Question

Let's say I've got a list l:

l: til 10

I want to show all values <3.

I tried this:

l . (l<3)

and

l[l<3]

But neither work. How should I do it?

Answer 1

I think where is what you're looking for here.

q)l:til 10
q)l where l<3
0 1 2