%% 
%%  A DANTE-Edition example
%% 
%%  Example 28-02-26 on page 540.
%% 
%%  Copyright (C) 2011 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[]{article}
\pagestyle{empty}
\setlength\textwidth{201.70511pt}
\setlength\parindent{0pt}

\usepackage{pst-func}

\begin{document}
\psset{xunit=1.2cm,yunit=10cm,plotpoints=200}
\begin{pspicture*}(-0.75,-0.07)(9.5,0.85)
 \psGammaDist[linewidth=1pt,linecolor=red]{0.01}{9}
 \psGammaDist[linewidth=1pt,linecolor=blue,alpha=0.3,beta=0.7]{0.01}{9}
 \psGammaDist[linewidth=1pt,linecolor=green,alpha=2,beta=2]{0.01}{9}
 \psGammaDist[linewidth=1pt,linecolor=cyan,alpha=2,beta=1]{0.01}{9}
 \psaxes[Dy=0.1]{->}(0,0)(9.5,.8)
\end{pspicture*}
\end{document}