GroIMP wiki - 02_user_tutorials:23_ode
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https://dokuwiki.grogra.de/lib/exe/fetch.php?media=wiki:dokuwiki.svgtext/html2025-12-10T16:32:23+00:00Anonymous (anonymous@undisclosed.example.com)How to use the ODE framework
https://dokuwiki.grogra.de/doku.php?id=02_user_tutorials:23_ode:getting_started&rev=1765384343&do=diff
How to use the ODE framework
Since GroIMP 1.0 a new ODE framework is available to modellers. This allows easy specification and solution of differential equations, which are used in many FSPMs. The key component of this framework is a new operator :'= called the deferred rate assignment operator. $y' = f(t,y),y(t0) = y0$$$
\begin{align}
k_1 &= y_n+\tfrac{1}{6}\left(k_1+2k_2+2k_3+k_4 \right)\\
t_{n+1} &= t_n+h
\end{align}$$
where $$ is the RK4 approximation of $$$
\begin{align}
k_1 &= f(t_n,y_…