On Tue, 17 Jun 2008 08:13:40 -0400, Phil Hobbs wrote: > [EMAIL PROTECTED] wrote: [snip] >> I have a physical system set up in which a body is supposed to >> accelerate and to get very close to lightspeed, while never really >> attaining it. After approx. 680 seconds, Python gets stuck and tells >> me the object has passed lightspeed. I put the same equations in >> Mathematica, again I get the same mistake around 680 seconds. So I >> think, I have a problem with my model! Then I pump up the >> WorkingPrecision in Mathematica to about 10. I run the same equations >> again, and it works! At least for the first 10,000 seconds, the object >> does not pass lightspeed. >> I concluded that I need Python to work at a higher precision. [snip] > You need to change your representation. Try redoing the algebra using > (c-v) as the independent variable, and calculate that.
Or represent the velocity as c*tanh(b), where b is the independent variable. If memory serves, this is the representation in which constant acceleration corresponds to db/dt = constant. -- To email me, substitute nowhere->spamcop, invalid->net. -- http://mail.python.org/mailman/listinfo/python-list