hup

HUP(C)    tests if the polynomial C is a Hurwitz-Polynomial.
    It tests if all roots lie in the left half of the complex
    plane 
       B=hup(C) is the same as 
       B=all(real(roots(c))<0) but much faster.
    The Algorithm is based on the Routh-Scheme.
    C are the elements of the Polynomial
    C(1)*X^N + ... + C(N)*X + C(N+1).

       HUP2 works also for multiple polynomials, 
       each row a poly - Yet not tested

 REFERENCES:
  F. Gausch 'Systemtechnik', Textbook, University of Technology Graz, 1993. 
  Ch. Langraf and G. Schneider 'Elemente der Regeltechnik', Springer Verlag, 1970.