# federgraph formula

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federgraph formula

Hi,
I am waiting for the tutorials, hope I can find something which plots a function z = f(x, y).
Vertices and the mesh probably need to be generated in a loop.
Have some rather good looking models and want to see how it looks, and if it is really so easy.

Here in the forum I am fighting with the spell checking and failed to select the source code in IE in order to copy it into notepad for editing/viewing.
But I really like the way the example models are presented on the home page!

--
Gustav Schubert
www.riggvar.de

Good question

Hi Gustav, good question.

The language support isosurfaces that are evaluated in 3D-space for every voxel in a 3D grid. The surface boundary is defined where f(x, y, z) = 0, for each 3D vertex (x, y, z). Now, if you have a surface z = g(x, y), that means that f(x, y, z) = 0 only if z = g(x, y), and hence f(x, y, z) = g(x, y) - z (i.e., you obtain the 2D surface by subtracting z from your 2D function.)

Here's a small example with g(x, y) = 2*cos(x)*cos(y)*exp((-x*x-y*y)*0.03):

http://www.onlinemodeler.com/projects/2d-surface

HTH,
Mattias

2D surface

I started up my Ubuntu machine with Firefox a Moment ago and voila, the 2D Surface appears on the left side and I can select text in the edit control on the right side, which was not the case using IE on my Windows 8 machine. So, it Looks good and I am looking Forward to test out some models. (This will take some time, cannot do it right now. As I am typing this, the spell checker makes the the first character of words into upper case.)
Thanks for the example, this should get me going.
Gustav