sysfact — system factorization
[S,Series]=sysfact(Sys,Gain,flag)
syslin list containing the matrices [A,B,C,D].
real matrix
string 'post' or 'pre'
syslin list
syslin list
If flag equals 'post', sysfact returns in S the linear
system with ABCD matrices (A+B*Gain, B , Gain, I), and Series,
a minimal realization of the series system Sys*S.
If flag equals 'pre', sysfact returns the linear system
(A+Gain*C, Gain , C, I) and Series, a minimal realization of the
series system S*Sys.