1. A method for simulating the operation of a circuit in a simulation model using a computer-based simulator, said simulation model having at least one nested subcircuit function and an output, said simulator using said output for generating results on the simulation of the operation of said circuit, said method comprising: (a) upon a change in an initialized signal in said simulation model, distributing said signal to one or more subcircuit functions that use said signal; (b) scheduling said subcircuit functions for execution according to a priority assigned to each subcircuit function, wherein the priority of a particular subcircuit function is determined by the number of interceding subcircuit functions between the output of said particular subcircuit function and the output of the simulation model, wherein the highest number is given the highest priority; and (c) executing one or more subcircuit functions with the highest priority to obtain function output, if said function output is the output of said simulation model, then providing the simulator with said function output, otherwise, providing said function output as a signal to one or more subcircuit functions that use said signal and returning to step (b).