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Lepton · 1:41+ Arse Scratcher

Does anyone have experience with these? I am considering writing some code on my spare time this summer, and N-body seems like an appropriate avenue. Specifically, I'd like to model galactic collisions using a few thousand randomly-distributed point masses. Do I have any easy alteratives to the Leapfrog method for orbits? Is the softening factor really necessary?

Dr. Borodog · Mad Scientist

You may be able to download some excellent codes that do just that if you don't want to reinvent the wheel.

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You will respect my philosophai.

Dr. Borodog · Mad Scientist

If you do intend to write your own code, made sure you use an energy-conserving finite difference method such as Euler-Cromer, rather than something like plain Euler. Regular Euler methods do not conserve energy, and your point masses will spiral away from your galactic centers.

The Euler-Cromer method uses the previous values of position and velocity to update the velocity, and the previous values of position and the NEW values of velocity to update the position.

If you need more details, let me know.

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You will respect my philosophai.