From B-parameters to Z-parameters
 In matrix form, the formula is
  Z=([0100]B+[1000])([000−1]B+[0010])−1
  While for each element, we obtain
 Z11Z12Z21Z22=−B21B22=−B211=−B21B11B22−B12B21=−B21B11
  
The formulas are obtained with the methods explained here.
        The MATLAB implementation can be found in circuitconversions on Gitlab.
 Definitions
   |   [V2−I2]=B[V1I1]   |    [V1V2]=Z[I1I2]   |