⍱ Nor

Compares two arguments which must consist only of 0's and 1's. If neither element compared is a 1, the result for that comparison is 1. Otherwise the result for that comparison is 0.

             1 ⍱ 1
       0
             1 ⍱ 0
       0
             0 ⍱ 0
       1
             0 0 0 1 0 ⍱ 1 1 1 1 0   (Each element in a vector is compared
       0 0 0 0 1                      with the corresponding element in a
                                      vector of equal size)

             TABLE←3 3⍴1 1 1 0 0 0 1 0 1
             0 ⍱ TABLE               (Each element in a matrix is compared
       0 0 0                          with 0)
       1 1 1
       0 1 0