def new_system(star_mass=1 | units.MSun,
star_radius=1 | units.RSun,
disk_minimum_radius=0.05 | units.AU,
disk_maximum_radius=10 | units.AU,
disk_mass=20 | MEarth,
accurancy=0.0001,
planet_density=3 | units.g / units.cm**3,
rng=None,
kepler=None):
central_particle = Particle()
central_particle.mass = star_mass
central_particle.position = (0, 0, 0) | units.AU
central_particle.velocity = (0, 0, 0) | units.kms
central_particle.radius = star_radius
central_particle.name = "star"
central_particle.type = "star"
central_particle.id = 0
if rng is None:
rng = numpy.random
converter = nbody_system.nbody_to_si(1 | units.MSun, 1 | units.AU)
if kepler is None:
kepler = Kepler(converter)
kepler.initialize_code()
m, r, f = new_planet_distribution(disk_minimum_radius, disk_maximum_radius,
disk_mass, accurancy)
planets = make_planets(central_particle,
m,
r,
density=planet_density,
phi=0,
theta=None,
kepler=kepler,
rng=rng)
planets.name = "planet"
planets.type = "planet"
for i in range(len(planets)):
planets[i].id = i
central_particle.planets = planets
kepler.stop()
p = Particles()
p.add_particle(central_particle)
return p
