Fyi, a picture of the program is below. I added a simple GUI front end for ease of use. It asks the user for the initial position/velocity vectors and to select the type of problem to solve (either supply a delta time or a delta Nu). Then when the user hits ‘RUN’ the program will generate all the properties of the orbit, keeps track of where the probe is as the simulation is running, display the ‘r’ vector, rp, ra as the probe is moving.

I still need to have the program generate the classical orbital elements.