On Jun 17, 3:13 pm, Phil Hobbs <[EMAIL PROTECTED]> wrote: > [EMAIL PROTECTED] wrote: > > On Jun 15, 7:43 pm, Peter Otten <[EMAIL PROTECTED]> wrote: > >> [EMAIL PROTECTED] wrote: > >>> On Jun 15, 6:58 pm, Christian Meesters <[EMAIL PROTECTED]> wrote: > >>>>> I do need speed. Is there an option? > >>>> Mind telling us what you *actually* want to achieve? (What do you want to > >>>> calculate?) > >>>> Christian > >>> Physical simulations of objects with near-lightspeed velocity. > >> How did you determine that standard python floats are not good enough? > > > 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. > > >> Everything beyond that is unlikely to be supported by the hardware and will > >> therefore introduce a speed penalty. > > > I have thought of that as well. However I have no choice. I must do > > these calculations. If you know of any way that is supported by the > > hardware, it will be terrific, but for now the slower things will have > > to do. > > You need to change your representation. Try redoing the algebra using > (c-v) as the independent variable, and calculate that. > > Cheers, > > Phil Hobbs
That was suggested. Problem is, that sometimes the velocities are near zero. So this solution, by itself, is not general enough. -- http://mail.python.org/mailman/listinfo/python-list
