Y must be a Boolean array.  X must be a Boolean array.  R is Boolean.  The value of R is the truth value of the proposition "neither X nor Y", and is determined as follows:

             X   Y     R
      
             0   0     1
             0   1     0
             1   0     0
             1   1     0

Example

      0 0 1 1 ⍱ 0 1 0 1
1 0 0 0