N-Body Dynamics Simulator
SIMULATES THE DYNAMICS OF N MASSIVE BODIES UNDER THE GRAVITATIONAL FORCE MASSES ARE SIMULATED AS POINT MASSES AND PROPAGATED FORWARD IN TIME VIA KICK-DRIFT-KICK DISCRETE TIME PROPAGATION (SEE n_body.simulate() BELOW)
AUTHOR: KYLE MORGENSTEIN (kylem@utexas.edu)
See www.kylemorgenstein.com for more
DATE: 11/28/2020
USAGE DOCUMENTATION
this example generates the movie file listed in the repository under "n_body_trials/*" using: G = 1 view_lim = 5 save = 100 run_time = 100
set initial conditions
init_conds = np.array([ [100,0,0,0,0,0,0], [1,0,-3,0,3,4,0], [1,0,3,0,-3,-4,0], [1,-3,0,0,0,-4,0], [1,3,0,0,0,4,0] ])
set experiment runtime
run_time = 10 [seconds]
initialize simulation class
sim = n_body(init_conds,run_time)
run simulation
sim.simulate()
plot the results
sets framerate for saved simulation - set to 0 to playback only
save = 100
automatically adjusts view to keep all masses in view
autoscroll = False
better to just generate the video and watch it at full speed
replay = False
scales view to [-view_lim, view_lim]
view_lim = 20
sim.plot(save,autoscroll,replay,view_lim)
saved simulations take up ~2-20 MB depedning on run_time generating the simulated video will take ~1-15 minutes depending on the length of simulation and your hardware
WAIT UNTIL THE CODE FINISHES RUNNING COMPLETLY BEFORE TRYING TO OPEN THE VIDEO FILE
OTHER HELPFUL USAGE TIPS
if you don'y care about selecting parameters, the entire simulation can be run inline as
n = 3
sim = n_body(3).run()
or
randomly generates 2-5 masses
sim = n_body().run()
The parameters you should focus on changing are:
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initial_conds - be creative with your initial conditions!
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self.G - strength of gravity
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self.S - damping on collisions
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run_time - simulation length
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scale - scales maximum radius of uniform random distribution for random poisition generation
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save - frames per second of simulation output video
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view_lim - axes ranges for visualization
DEV NOTES:
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visualizations are mapped from X-Y-Z space to the X-Y plane for visualization
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visualizations are shown in the Center-of-Mass (COM) frame
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everything should work but I wrote this in three days so pls don't roast me on Twitter for my hacky code thx <3
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lmk if something is broken though, thx!!!
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have fun :)