1. A method for a continuation model predictive control (CMPC) of a system, comprising: determining at least a part of a preconditioner using an approximate coefficient function; determining a solution vector by solving a matrix equation of the CMPC with a coefficient matrix defined by an exact coefficient function at a current time step of a control using an iterative method with the preconditioner, wherein the approximate coefficient function applied to a vector approximates a result of an application of the exact coefficient function to the vector; and generating a control signal for controlling the system using the solution vector, wherein steps of the method are performed by at least one processor.