def simulation(par):
saturn_a, saturn_e = par
rebound.reset()
rebound.set_min_dt(0.1)
# These parameters are only approximately those of Jupiter and Saturn.
sun = rebound.Particle(m=1.)
rebound.particle_add(sun)
jupiter = rebound.particle_add(primary=sun,m=0.000954, a=5.204, anom=0.600, omega=0.257, e=0.048)
saturn = rebound.particle_add(primary=sun,m=0.000285, a=saturn_a, anom=0.871, omega=1.616, e=saturn_e)
rebound.move_to_center_of_momentum()
rebound.megno_init(1e-16)
rebound.integrate(1e4*2.*np.pi)
return [rebound.get_megno(),1./(rebound.get_lyapunov()*2.*np.pi)] # returns MEGNO and Lypunov timescale in years
def simulation(par):
S, dt,e0 = par
rebound.reset()
rebound.set_integrator("wh")
#rebound.set_integrator("whfast")
rebound.set_dt(dt)
rebound.particle_add(m=1.)
rebound.particle_add(m=0.,a=1.,e=e0)
#rebound.move_to_center_of_momentum()
#rebound.megno_init(1.e-16)
particles = rebound.particles_get()
def starkforce(): # need to put inside simulation(par) to have access to S and particles
particles[1].ax += -S
rebound.set_additional_forces(starkforce)
rebound.integrate(50000.*np.pi)
return [rebound.get_megno(), rebound.get_t()]
# Import the rebound module
import sys; sys.path.append('../')
import rebound
from rebound import Particle
import numpy as np
from interruptible_pool import InterruptiblePool
for i in np.linspace(-2.*np.pi,2.*np.pi,1000):
rebound.reset()
rebound.set_integrator("whfast-nocor")
rebound.set_dt(0.01*2.*np.pi)
try:
rebound.particle_add(m=1.)
rebound.particle_add(m=0., a=1., e=1.01, anom=i)
particles = rebound.particles_get()
print particles[1].x, particles[1].y, i
#rebound.step()
#print particles[1].x, particles[1].y, i
except:
pass
# Import the rebound module
import sys; sys.path.append('../')
import rebound
from rebound import Particle
# Set variables (defaults are G=1, t=0, dt=0.01)
k = 0.01720209895 # Gaussian constant
rebound.set_G(k*k) # Gravitational constant
# Setup particles (data taken from NASA Horizons)
# This could also be easily read in from a file.
rebound.particle_add( Particle( m=1.00000597682, x=-4.06428567034226e-3, y=-6.08813756435987e-3, z=-1.66162304225834e-6, vx=+6.69048890636161e-6, vy=-6.33922479583593e-6, vz=-3.13202145590767e-9) ) # Sun
rebound.particle_add( Particle( m=1./1047.355, x=+3.40546614227466e+0, y=+3.62978190075864e+0, z=+3.42386261766577e-2, vx=-5.59797969310664e-3, vy=+5.51815399480116e-3, vz=-2.66711392865591e-6) ) # Jupiter
rebound.particle_add( Particle( m=1./3501.6, x=+6.60801554403466e+0, y=+6.38084674585064e+0, z=-1.36145963724542e-1, vx=-4.17354020307064e-3, vy=+3.99723751748116e-3, vz=+1.67206320571441e-5) ) # Saturn
rebound.particle_add( Particle( m=1./22869., x=+1.11636331405597e+1, y=+1.60373479057256e+1, z=+3.61783279369958e-1, vx=-3.25884806151064e-3, vy=+2.06438412905916e-3, vz=-2.17699042180559e-5) ) # Uranus
rebound.particle_add( Particle( m=1./19314., x=-3.01777243405203e+1, y=+1.91155314998064e+0, z=-1.53887595621042e-1, vx=-2.17471785045538e-4, vy=-3.11361111025884e-3, vz=+3.58344705491441e-5) ) # Neptune
rebound.particle_add( Particle( m=0, x=-2.13858977531573e+1, y=+3.20719104739886e+1, z=+2.49245689556096e+0, vx=-1.76936577252484e-3, vy=-2.06720938381724e-3, vz=+6.58091931493844e-4) ) # Pluto
# Set the center of momentum to be at the origin
rebound.move_to_center_of_momentum()
# Get the particle data
# Note: this is a pointer and will automatically update as the simulation progresses
particles = rebound.particles_get()
# timestep counter
steps = 0
# Integrate until t=1e6 (unit of time in this example is days)
while rebound.get_t()<1e6:
rebound.step()
steps += 1
# Print particle positions every 100 timesteps
# Import the rebound module
import sys; sys.path.append('../')
import rebound
# Set variables (defaults are G=1, t=0, dt=0.01)
#rebound.set_G(1.)
#rebound.set_t(0.)
#rebound.set_dt(0.01)
# Add particles
# All parameters omitted are set to 0 by default.
rebound.particle_add( m=1. ) # Star
rebound.particle_add( m=1e-3, x=1., vy=1. ) # Planet
# Move particles so that the center of mass is (and stays) at the origin
rebound.move_to_center_of_momentum()
# Integrate until t=100 (roughly 16 orbits)
rebound.integrate(100.)
# Modify particles
# As an example, we are reverting the velocities
particles = rebound.particles_get()
for i in range(rebound.get_N()):
particles[i].vx *= -1.
particles[i].vy *= -1.
particles[i].vz *= -1.
# Integrate another 100 time units, until t=200
rebound.integrate(200.)
# Import the rebound module
import sys; sys.path.append('../')
import rebound
from rebound import Particle
# Add particles
# We work in units where G=1.
rebound.particle_add( Particle(m=1.) ) # Test particle
rebound.particle_add( Particle(m=1e-3,x=1.,vy=1.) ) # Planet
# Move particles so that the center of mass is (and stays) at the origin
rebound.move_to_center_of_momentum()
# You can provide a function, written in python to REBOUND.
# This function gets called every time the forces are evaluated.
# Simple add any any additional (non-gravitational) forces to the
# particle accelerations. Here, we add a simple drag force. This
# will make the planet spiral into the star.
particles = rebound.particles_get() # Pointer to the particle structure
N = rebound.get_N()
def dragforce():
dragcoefficient = 1e-2
for i in range(N):
particles[i].ax += -dragcoefficient * particles[i].vx
particles[i].ay += -dragcoefficient * particles[i].vy
particles[i].az += -dragcoefficient * particles[i].vz
# Tell rebound which function to call
rebound.set_additional_forces(dragforce)
# Integrate until t=100 (roughly 16 orbits at 1 AU)
# Import the rebound module
import sys
sys.path.append("../")
import rebound
from rebound import Particle
# Set variables (defaults are G=1, t=0, dt=0.01)
# rebound.set_G(1.)
# rebound.set_t(0.)
# rebound.set_dt(0.01)
# Add particles
rebound.particle_add(Particle(m=1.0)) # Star
rebound.particle_add(Particle(m=1e-3, x=1.0, vy=1.0)) # Planet
# Move particles so that the center of mass is (and stays) at the origin
rebound.move_to_center_of_momentum()
# Integrate until t=100 (roughly 16 orbits)
rebound.integrate(100.0)
# Modify particles
# As an example, we are reverting the velocities
particles = rebound.particles_get()
for i in range(rebound.get_N()):
particles[i].vx *= -1.0
particles[i].vy *= -1.0
particles[i].vz *= -1.0
# Integrate another 100 time units, until t=200
import sys; sys.path.append('../')
import rebound
# Add a particle at the origin with mass 1
rebound.particle_add(m=1.)
# Add a particle with mass 1e-3 on a Keplerian
# orbit around the center of mass (including all
# particles added so far) with semi-major axis 1
rebound.particle_add(m=1e-3, a=1.)
# Add a test particle (mass=0) on a Keplerian orbit
# around the center of mass (both particles added above)
# with a semi-major axis of 2 and eccentricity of 0.1.
# This corresponds to Jacobi coordinates.
rebound.particle_add(a=1., e=0.1)
# Move all particles to the-center-of-momentum frame.
rebound.move_to_center_of_momentum()
# Print the resulting cartesian coordinates.
p = rebound.particles_get()
for i in range(rebound.get_N()):
print(p[i].m, p[i].x, p[i].y, p[i].z, p[i].vx, p[i].vy, p[i].vz)
# Integrate for 100 time units
rebound.integrate(100.)