If 'y0' or 'param_values' are not passed to the CupSodaSimulator, the code should should use the values from the model and assume that they are constant for all simulations. If neither are passed, it should assume only a single simulation and maybe throw a warning.
Issue from https://github.com/LoLab-VU/pysb-cupsoda/issues/6 originally by @lh64:
If 'y0' or 'param_values' are not passed to the CupSodaSimulator, the code should should use the values from the model and assume that they are constant for all simulations. If neither are passed, it should assume only a single simulation and maybe throw a warning.