Re: visualizing fields near charged objects

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

I should have added, in the message about John's Excel
project, that the infinity (place where V is forced to be
zero) is too close. Suppose the disk diameter is 15 cells.
to simulate a disk in empty space the matrix should be
at least 300 by 300 cells, or more. Or 3000 by 3000
if the disk diameter is 150 cells. That would slow the
program a lot but who cares? Let the computer run for
hours, save the matrix and play with it later to get the
S(r) distribution. Right?
Ludwik Kowalski

Bob Sciamanda wrote:

> I once used this averaging algorithm to solve a boundary value Laplace
> problem with MATHCAD.  It is tedious to set up (stick to a simple geometry)
> and very tedious in lengthy computing time.  But the advantage is that
> MathCad immediately gives you very enlightening graphs of the results: x vs
> y plots, contour maps, little E field arrows or even perspective drawings of
> the potential.
> Anyone interested (it needs MathCad 6 Plus or better) can get my code by
> asking.  It takes some slight "trickery" to get MathCad to iterate.
>
> Bob
>
> Bob Sciamanda (W3NLV)
> Physics, Edinboro Univ of PA (em)
> trebor@velocity.net
> www.velocity.net/~trebor