I read on wikipedia that the E field obeys the superposition principle, meaning I can just add up the individual fields generated by all the charges in a system to get it. While this is nice for creating the E field, can I do the same for the H field? I ask because I want to simulate a dynamo and this involves a permanent magnet. Being able to just add in a dipole field anywhere has an almost heart-warming (and seemingly too good to be true) feeling of convenience to it. Note: I really, really do not want to simulate a magnet using micro-current loops because of the severe stability issues and the obvious fact that it affects the electric field.