SS2TF State-space to transfer function conversion.
[NUM,DEN] = SS2TF(A,B,C,D,iu) calculates the transfer function:
NUM(s) -1
H(s) = -------- = C(sI-A) B + D
DEN(s)
of the system:
.
x = Ax + Bu
y = Cx + Du
from the iu'th input. Vector DEN contains the coefficients of the
denominator in descending powers of s. The numerator coefficients
are returned in matrix NUM with as many rows as there are
outputs y.