[Gnuplot-info] Plotting 3D radiation patterns

[bernhard <q....@gm...>]

Hi,

I want to plot a 3D antenna radiation pattern obtained from a field 
simulator. The data is stored in a csv with the following structure:

#x, #y, #z, (#value)

The fourth column #value specifies the magnitude of the antenna gain in 
the direction (0,0,0) - (x,y,z).

At first I want to plot a mesh of the (x,y,z) data, which should be 
non-transparent (as it is supposed to be a surface plot).

With

splot "datafile.csv"

I get a (more or less nice) graph with the different points specified in 
the datafile. How can I create a surface plot using these points with 
the color of the plot representing the distance to the origin? Or can I 
use #value somehow to display a special color to the surface?


At the end, it should look like this: 
http://people.ee.ethz.ch/~FVTD/images/dra/DRA_Patt_3D_Lin.gif (without 
the animation, just a single frame) or this: 
http://www.hindawi.com/journals/ijap/2008/floats/854012/thumbnails/854012.fig.005a_th.jpg

Any help would be deeply appreciated!


Greetings,
	Bernhard