coff - resolvent (cofactor method)
coff computes R=(s*eye()-M)^-1 for M a real matrix. R is given by N/d.
N = numerator polynomial matrix.
d = common denominator.
var character string ('s' if omitted)
M=[1,2;0,3]; [N,d]=coff(M) N/d inv(%s*eye()-M)