Picking Out Elements Using a Logical List

[Didier Lachieze]

Nice function ! I was expecting it would be very easy to implement it with the current Prime list functions but I've not found a simple solution without a FOR loop.
So, here is another way to do it:

Code:

EXPORT BOOLLIST(LA,LB)
BEGIN
  LOCAL LC,k;
  LC:={};
  FOR k FROM 0 TO SIZE(LA)-1 DO
    IF LB(k MOD SIZE(LB)+1) THEN 
      LC(0):=LA(k+1); 
    END;
  END;
  RETURN LC;
END;

Note: storing to LC(0) is used to add an element to the list LC.