def simulation(par):
    saturn_a, saturn_e = par
    rebound.reset()
    rebound.integrator = "whfast-nocor"
    rebound.min_dt = 5.
    rebound.dt = 1.

    # These parameters are only approximately those of Jupiter and Saturn.
    sun = rebound.Particle(m=1.)
    rebound.add(sun)
    jupiter = rebound.add(primary=sun,
                          m=0.000954,
                          a=5.204,
                          anom=0.600,
                          omega=0.257,
                          e=0.048)
    saturn = rebound.add(primary=sun,
                         m=0.000285,
                         a=saturn_a,
                         anom=0.871,
                         omega=1.616,
                         e=saturn_e)

    rebound.move_to_com()
    rebound.init_megno(1e-16)
    rebound.integrate(1e3 * 2. * np.pi)

    return [
        rebound.calculate_megno(),
        1. / (rebound.calculate_lyapunov() * 2. * np.pi)
    ]  # returns MEGNO and Lypunov timescale in years
Exemple #2
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def simulation(par):
    saturn_a, saturn_e = par
    rebound.reset()
    rebound.integrator = "whfast"
    rebound.integrator_whfast_safe_mode = 0 
    rebound.dt = 5.
    
    # These parameters are only approximately those of Jupiter and Saturn.
    rebound.add(m=1.)
    rebound.add(m=0.000954, a=5.204, anom=0.600, omega=0.257, e=0.048)
    rebound.add(m=0.000285, a=saturn_a, anom=0.871, omega=1.616, e=saturn_e)

    rebound.move_to_com()
    rebound.init_megno(1e-16)
    rebound.integrate(5e2*2.*np.pi) # integrator for 500 years

    return [rebound.calculate_megno(),1./(rebound.calculate_lyapunov()*2.*np.pi)] # returns MEGNO and Lypunov timescale in years
def simulation(par):
    saturn_a, saturn_e = par
    rebound.reset()
    rebound.integrator = "whfast-nocor"
    rebound.min_dt = 5.
    rebound.dt = 1.
    
    # These parameters are only approximately those of Jupiter and Saturn.
    sun     = rebound.Particle(m=1.)
    rebound.add(sun)
    jupiter = rebound.add(primary=sun,m=0.000954, a=5.204, anom=0.600, omega=0.257, e=0.048)
    saturn  = rebound.add(primary=sun,m=0.000285, a=saturn_a, anom=0.871, omega=1.616, e=saturn_e)

    rebound.move_to_com()
    rebound.init_megno(1e-16)
    rebound.integrate(1e3*2.*np.pi)

    return [rebound.calculate_megno(),1./(rebound.calculate_lyapunov()*2.*np.pi)] # returns MEGNO and Lypunov timescale in years