an> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="idp35241728"></a><h2>Description</h2>
<p>The Runge-Kutta method of fourth order is one standard method for solving ordinary differential equations and is widely used, see also <a href="http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods" target="_top">en.wikipedia.org/wiki/Runge-Kutta_methods</a> The m