[Bug-apl] Select from a two-dimensional array

[Elias Mårtenson]

Here's a problem I've had on multiple occasions, and I have yet to figure out a nice generic way of dealing with it.

For a one-dimensional array, I can easily select elements based on a bitmap:

      0 0 1 0 0 0/⍳6

3

Sometimes I want to do the same from a two (or more) dimensional array:

      a

1 2 3

4 1 2

      b

0 0 1

0 0 0

      b/a

RANK ERROR

      b/a

      ^ ^

How to do this?

Regards,

Elias