monad      ⊂      ,    ⍪    ⌹    ⍉    f⌿    f⍀    ⊖

           {⍵[⍋⍵]}   {⍵[⍒⍵]}    {⍵[⍋⍵;]}   {⍵[⍒⍵;]}


dyad       {⍺⍵}   ,    ⍪    ⌹    ⍉    x/y   x⌿y

           ≡    ≢    ⍳    ⌷    ↑   ↓   f

where f is a primitive scalar dyadic function