As an example of ODEs, the following equations are the Lotka–Volterra equations (also known as the predator–prey equations)

where r is the rabbit population, and f  is the population of foxes. This is an example of a system of two coupled ODEs.

Enter these equations as a*r-b*r*f-rt for r and -c*f+d*r*f-ft for f, where a, b, c, and d are scalar values defined using the Parameters node’s Settings window. For this first-order ODE, specify initial values for r and f.