double coprime factorization
[N,M, X,Y, NT,MT, XT,YT] = dcf(G) [N,M, X,Y, NT,MT, XT,YT] = dcf(G, polf, polc) [N,M, X,Y, NT,MT, XT,YT] = dcf(G, polf, polc, tol)
syslin list (continuous-time linear system)
respectively the poles of XT and YT and the poles of N and M (default values =-1).
real threshold for detecting stable poles (default value 100*%eps).
linear systems represented by syslin lists
returns eight stable systems (N,M,X,Y,NT,MT,XT,YT)
for the doubly coprime factorization
G must be stabilizable and detectable.