%% 
%%  A DANTE-Edition example
%% 
%%  Example 30-04-15 on page 614.
%% 
%%  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{225.70511pt}
\setlength\parindent{0pt}

\usepackage{pstricks-add}

\begin{document}
\psset{unit=0.5cm,plotpoints=500,
  method=rk4}
\begin{pspicture}(-6,-4)(5,6)
  \psaxes{->}(0,0)(-6,-4)(5,6)
  \psplotDiffEqn[linewidth=1.5pt,
    whichabs=1,whichord=0,
    algebraic]{0}{24}{5 0}%
      {y[1]|-y[1]/4-2*y[0]}
\end{pspicture}
\end{document}