Determining a next value of a system-simulation parameter in response to a representation of a plot having the parameter as a dimension

An embodiment of an apparatus includes a simulator, generator, and determiner. The simulator is configured to simulate a system and to propagate at least one state of the simulated system through time in response to a value of a parameter, and the generator is configured to generate a representation of a region of a plot having dimensions that respectively correspond at least to the parameter and to a characteristic of a state of the simulated system. And the determiner is configured to determine a next value of the parameter in response to the representation of the region.