Example

> abs(2.34)
     2.34
> abs(-2.34)
     2.34
> abs(-2.34 + 4j)
     4.63
> sqrt((-2.34)^2 + (4)^2)
     4.63
> b = [ -3.4, 4.6097; 3+4j , -34.5653 -0.01j]
 b =
               -3.4 + 0i               4.61 + 0i
                  3 + 4i           -34.6 - 0.01i
> abs(b)
      3.4       4.61  
        5       34.6