Abstract:
In this paper the problem of
measuring the robustness of stability for a perturbed discrete time
nonlinear system is studied. Various stability radii are introduced
and their values for the nonlinear system and its linearization are
compared and it is shown that they generically coincide. Some
examples are presented showing that it is sometimes necessary to
consider the nonlinear system directly, and not simply to rely on the
information provided by the linearization.