%% 
%%  Ein Beispiel der DANTE-Edition
%% 
%% 
%%  Copyright (C) 2010 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{190.324pt}
\setlength\parindent{0pt}
\StartShownPreambleCommands
\usepackage{pst-electricfield}
\StopShownPreambleCommands
\begin{document}
\begin{pspicture*}(-5,-5)(5,5)
\psgrid[subgriddiv=0,gridcolor=lightgray,
  griddots=10]
\psElectricfield[Q={[1 -2 0][-1 2 0]},
  linecolor=red]
\psEquipotential[Q={[1 -2 0][-1 2 0]},
  linecolor=blue](-5,-5)(5,5)
\psEquipotential[Q={[1 -2 0][-1 2 0]},
  linecolor=green,Vmin=0,Vmax=0](-5,-5)(5,5)
\end{pspicture*}
\end{document}