%% 
%%  Ein Beispiel der DANTE-Edition
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%%  7. Auflage
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%%  Beispiel 32-03-78 auf Seite 771.
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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{193.16928pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{pst-stru}
%StopShownPreambleCommands
\begin{document}
\def\BMdistributed#1#2#3{#2 x sub 0.5 #1 x mul mul mul #3 mul}
\begin{pspicture}(-1,-1.4)(11,2)
\pnode(0,0){A}\pnode(10,0){B}\rput{0}(A){\hinge}\rput{0}(B){\roller}
\rput(0,-1){\Large A}\rput(10,-1){\Large B}\psline[linecolor=blue](A)(B)
\pscustom[linecolor=blue,linewidth=1pt,fillstyle=solid,fillcolor=yellow]{%
  \psplot[linecolor=blue]{0}{10}{\BMdistributed{12}{10}{0.01}}\psline(10,0)(0,0)}
\psset{arrowsize=1.5mm}\multido{\nStart=0.0+0.2}{51}{%
 \pnode(\nStart,0){E1}\pnode(!/x \nStart\space def x \BMdistributed{12}{10}{0.01}){E2}
 \psline[linecolor=blue,arrowinset=0,arrowsize=1mm]{->}(E2)(E1) }
\end{pspicture}
\end{document}