Lotka-Volterra 4d

Integrating the default problem gives a quasi-periodic trajectory; here is its projection onto the $(q_1, q_2)$ plane:

using GeometricProblems.LotkaVolterra4d
using GeometricIntegrators: integrate, Gauss
using CairoMakie

sol = integrate(odeproblem(), Gauss(2))
plot_phase_portrait(sol)