%% 
%%  Ein Beispiel der DANTE-Edition
%%  
%%  7. Auflage
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%%  Beispiel 14-03-27 auf Seite 228.
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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{145.16928pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{pst-plot}
%StopShownPreambleCommands
\begin{document}
\psset{xunit=0.025cm,yunit=4cm}
\begin{pspicture}(-0.1,-0.1)(190,1.1)
 \psgrid[subgriddiv=0,griddots=5,
  gridlabels=0pt,xunit=30,yunit=0.2](6,5)
 \psaxes[linewidth=1pt,ticks=none,Dx=30,
  Dy=0.2]{->}(190,1.1)
 \uput{0.5}[0](180,0){$\mathbf{\alpha}$}
 \uput{0.5}[90](0,1){$\mathbf{I/I_0}$}
 \psplot[linewidth=1.5pt]{0}{180}{1 x 180 div sub 1
  6.28 div x 2 mul sin mul add abs sqrt}
 \psplot[linewidth=1.5pt,linestyle=dashed]{90}{180}{
  2 x 90 div sub x 2 mul cos 2 add mul x
  2 mul sin 3 3.15 div mul add abs sqrt}
 \rput(45,0.85){$\varphi=0$}
 \rput(120,0.9){$\varphi=\pi/2$}
\end{pspicture}
\end{document}