1. A method for controlling the operation of a nonlinear system responsive to parametric signals for sustaining and tracking a chaotic system, said method comprising the steps: (a) representing a nonlinear dynamic system as a function of a system parameter and an output value; (b) generating a parametric signal corresponding to an initial value of the system parameter; (c) producing an output signal corresponding to an output value from the nonlinear system in response to the parametric signal; (d) calculating iterations of the function; and (e) generating a new parametric value if a current iteration falls within a predetermined neighborhood of a previous iteration.