%% 
%%  Ein Beispiel der DANTE-Edition
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%%  7. Auflage
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%%  Beispiel 29-02-4 auf Seite 637.
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%%  Copyright (C) 2016 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
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\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{352.81416pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{pstricks-add}\psset{yunit=0.75cm,xunit=1.1cm}
%StopShownPreambleCommands
\begin{document}
  \begin{pspicture}[showgrid=true](-2,-3.4)(3,3.4)
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  \psRelLine[linecolor=magenta,angle=-90](A)(B){0.5}{EndNode}\qdisk(EndNode){2pt}
\end{pspicture}\hfill
\begin{pspicture}[showgrid=true](-2,-3.4)(3,3.4)
  \pnode(-1,0){A}\pnode(3,2){B}\psline[linecolor=red](A)(B)
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  \psRelLine[linecolor=blue,angle=30](-1,0)(B){0.5}{EndNode}\qdisk(EndNode){2pt}
  \psRelLine[linecolor=blue,angle=-30](A)(B){0.5}{EndNode}  \qdisk(EndNode){2pt}
  \psRelLine[linecolor=magenta,angle=90](-1,0)(3,2){0.5}{EndNode}\qdisk(EndNode){2pt}
  \psRelLine[linecolor=magenta,angle=-90](A)(B){0.5}{EndNode}\qdisk(EndNode){2pt}
\end{pspicture}
\end{document}