Computation of stability radius for polynomials

A polynomial is stable if all its roots have negative real part, and unstable otherwise. For a stable polynomial, the distance to the near-est unstable polynomial is an important parameter in control theory for example. In this paper, we focus on this distance called the sta-bility radius of polynomial p. We propose to modify the level contour function of the pseudozero set to derive a bisection algorithm that computes an arbitrary accurate approximation of this stability radius. Numerical simulations and comparisons with pseudozero graphics are here after presented