eqpot.txt

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Equipotentials

These are boundaries which set the potential as a function of time.
They only produce time-varying behavior in electrostatic simulations.

In electromagnetic simulations they only serve to set up the
initial electric fields.

Equipotentials are implemented by means of superposition--
Laplace's equation is solved to get a potential profile for
each equipotential boundary at t=0, with all the other boundaries
held to zero.

At t=T, poisson's equation is solved with all boundaries set to 
zero.  Then, a scaled profile for each equipotential is added
to the solution for potential.

Because of the way the solve works:

1)  DO NOT PUT TWO EQUIPOTENTIAL BOUNDARIES IN THE SAME PLACE.
    This will cause very strange behavior.

2)  DO NOT USE TOO MANY EQUIPOTENTIAL BOUNDARIES.
    Each equipotential boundary requires an array and
    an array-addition per timestep.