1. A method for a continuation model predictive control (CMPC) of a system by a controller having at least one processor and a memory, comprising: selecting from the memory a model of the system, an approximate coefficient function and an exact coefficient function, wherein the approximate coefficient functions applied to a vector returns a product of an approximate coefficient matrix and the vector, and wherein the exact coefficient functions applied to the vector returns a product of an exact coefficient matrix and the vector; determining at least a part of a preconditioner using the approximate coefficient function; determining a solution vector by solving a matrix equation of the CMPC with a coefficient matrix defined by the exact coefficient function at a current time step of a control using an iterative method with the preconditioner; and generating a control signal for controlling the system by the controller using the solution vector.