45 lines
1.7 KiB
Python
Executable File
45 lines
1.7 KiB
Python
Executable File
#!/usr/bin/python
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# -*- coding:utf-8 -*-
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from sys import exit as sysexit
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import numpy as np
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import matplotlib.pyplot as plt
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from lib.objects import Body, System
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from lib.plots import display_parameters
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from lib.units import *
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def main():
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#initialisation
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m = np.array([1., 1., 0])*Ms # Masses in Solar mass
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a = np.array([1., 1., 5.])*au # Semi-major axis in astronomical units
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e = np.array([0., 0., 1./4.]) # Eccentricity
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psi = np.array([0., 0., 0.])*np.pi/180. # Inclination of the orbital plane in degrees
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x1 = np.array([0., -1., 0.])*a[0]
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x2 = np.array([0., 1., 0.])*a[1]
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x3 = np.array([np.cos(psi[2]), 0., np.sin(psi[2])])*a[2]
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q = np.array([x1, x2, x3])
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v1 = np.array([np.sqrt(G*m[1]**2/((m[0]+m[1])*np.sqrt(np.sum((q[0]-q[1])**2)))), 0., 0.])
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v2 = np.array([-np.sqrt(G*m[0]**2/((m[0]+m[1])*np.sqrt(np.sum((q[0]-q[1])**2)))), 0., 0.])
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v3 = np.array([0., np.sqrt(G*(m[0]+m[1])*(2./np.sqrt(np.sum(q[2]**2))-1./a[2])), 0.])
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v = np.array([v1, v2, v3])
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bodylist = []
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for i in range(3):
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bodylist.append(Body(m[i], q[i], v[i]))
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dyn_syst = System(bodylist)
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dyn_syst.COMShift()
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duration, step1, step2 = 100*yr, 1e4, 1e5
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E1, L1 = dyn_syst.leapfrog(duration, step1, recover_param=True)#, display=True)
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E2, L2 = dyn_syst.leapfrog(duration, step2, recover_param=True)#, display=True)
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#E1, L1 = dyn_syst.hermite(duration, step1, recover_param=True)#, display=True)
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#E2, L2 = dyn_syst.hermite(duration, step2, recover_param=True)#, display=True)
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parameters = [duration, [step1, step2], dyn_syst, "leapfrog"]
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display_parameters([E1, E2], [L1, L2], parameters=parameters, savename="3bodies_leapfrog")
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return 0
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if __name__ == '__main__':
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sysexit(main())
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