One Small Suggestion This app is a fantastic tool. My thought is that since many dynamical systems take place on a torus or a cylinder, the user should be able to specify. All I mean is that the user should be able to state whether a particle flying off to the right will keep going or at some point reappear on the left. That would be a cylinder, for a torus you would have the same property on the top and bottom as well. That would expand the use of this app to angular dynamical systems like the damped driven pendulum. Cheers!