Yes, the parameters you're differentiating with respect to need to be floats.
Though there might be potential for extending the frameworks to e.g. differential cryptanalysis - I'm not knowledgeable enough about it to say how much differential cryptanalysis can be done programmatically.
Though there might be potential for extending the frameworks to e.g. differential cryptanalysis - I'm not knowledgeable enough about it to say how much differential cryptanalysis can be done programmatically.