x  ←  +.×

    A  ←  ↑A*¨⊂A←⍳4   ⍝  Same  A  as in other examples (1 1 1 1⍪ 2 4 8 16⍪ 3 9 27 81,[0.5] 4 16 64 256)
    B  ←  ⌹A          ⍝  Matrix inverse of A

    'F6.2' ⎕FMT A x B
1.00  0.00  0.00  0.00
0.00  1.00  0.00  0.00
0.00  0.00  1.00  0.00
0.00  0.00  0.00  1.00