This example shows how to construct a
dielectric profile for a wire with a 
circular cross-section. Periodicity 
assumed in the z direction.
A circular cross-section with the
edges smoothened can be constructed 
using the Smoothness parameter.

Run coffee.py with the given input file, in, 
and visualize the epsilon profile using 
plot_eps.py:

$path_to_coffee_folder/coffee.py in
$python plot_eps.py

Note that this is a fictitious system 
to demonstrate how the profile can
be constructed.
