On Nov 28, 1:28 pm, Wimpie wrote:
Hello,

I made an excel sheet to simulate Fresnel diffraction patterns. I used
a 2 way data table to generate the "infinitesimal" contributions from
the EM field. After summation of the contributions in the 2D tables,
a have one result cell (that holds |E|) and three input cells
(variables) for x-, y-, and z- coordinate for the observation point.
When I change the coordinates manually, the results seem OK.


Does somebody know a solution for this (I do not prefer a VB one)?


Excel is a notoriously bad thing to use for statistics or numerical
analysis. Aside from the pain the rear nature once you get past
trivial manipulations, there are some serious calculation issues to
worry about (since Excel isn't rigorously tested for its
implementation, these also change as versions change)

http://www.burns-stat.com/pages/Tuto...addiction.html
covers a lot of the problems.

You're better off biting the bullet and using something like Matlab
(academic license $100) or Octave (free, but not quite as fancy as
Matlab, but mostly compatible) or similar products.