SOrry if this message is a little confused, it most probably reflects the state of the author!
I have made a small program that plots the orbit of a planet in visual python using visual.vector for all values. If i run the program it is clear that the orbit is non-keplerian as the planets gradually moves away from the sun. I am pretty sure the orbit should be keplerian so i guess there must be some source of error in the program. I am using "from __future__ import division" and the initial conditions I have are from NASA's horizons system, all values are accuracte to more than 10 decimal places. I was wondering if there was a way to specify the type of number used by visual.vector, for example, when using an array it is possible to specify the type as float64. If visual.vector was using a smaller amount of memory to store the number could this be the source of the error I am finding? If not what else could be the culprit? I have used a 4th order RK method which I have previously produced Keplerian orbits with. I hope I have made some sense here and look forward to any input Many Thanks Ben -- http://mail.python.org/mailman/listinfo/python-list
