fpzp_new

FPZP_NEW Fractional power zero-pole pair approximation by Newton method

   Approximates a fractional power pole-zero pair in form 

                                      alpha
                            (b*s + 1)
                            ---------
                            (a*s + 1)

  where alpha is the fractional order (power), b and a are coefficients
  such that w_zero = 1/b, w_pole = 1/a.

  Usage: [G, J, err] = fpzp_new(b, a, alpha, N, w, retol)

         where optional parameters are

                   N (default: 2) - approximation order,

                   w - [wb; wh] - frequency range, where index J is
                                  calculated. Defaults to [0.0001; 10000].
                   
                   retol (default: []) - tolerance for model reduction
                                         using a matching zero-pole
                                         reduction method realized by
                                         applying the minreal() function.

  See also: carlapp, minreal