system matrix to descriptor
Des = sm2des(Sm);
polynomial matrix (pencil system matrix)
descriptor system (list('des',A,B,C,D,E))
list('des',A,B,C,D,E)
Utility function: converts the system matrix:
Sm = [-sE + A B; [ C D]
to descriptor system Des=list('des',A,B,C,D,E)).
Des=list('des',A,B,C,D,E)