Monadic Rho means

Shape Of

      mat
1  2  3  4
5  6  7  8
9 10 11 12

      ⍴ mat
3 4
      ⍴⍴ mat
2
      ⍴ 'your boat'
9
      ⍴ 7

      ⍴⍴ 7
0

Dyadic Rho means

Reshape

      2 3 4 ⍴ 1 2 3 4 5 6 7
1 2 3 4
5 6 7 1
2 3 4 5
       
6 7 1 2
3 4 5 6
7 1 2 3

Language Elements