⌈/(3⍴2)⊤2
DOMAIN ERROR
      ⌈/(3⍴2)⊤2
      ^ ^
      A←(3⍴2)⊤2
      A
0 1 0
      B←0 1 0
      ⌈/B
1
      A≡B
1
      ⌈/A
DOMAIN ERROR
      ⌈/A
      ^ ^
      10⎕CR¨ 'AB'
  A←3⍴0,1,0J0    B←3⍴0,1,0