def test7(self):
print "Test7: Testing effect of Huayno parameter epsilon_squared"
convert_nbody = nbody_system.nbody_to_si(1.0 | units.MSun,
1.0 | units.AU)
particles = datamodel.Particles(2)
sun = particles[0]
sun.mass = 1.0 | units.MSun
sun.position = [0.0, 0.0, 0.0] | units.AU
sun.velocity = [0.0, 0.0, 0.0] | units.AU / units.yr
sun.radius = 1.0 | units.RSun
earth = particles[1]
earth.mass = 5.9736e24 | units.kg
earth.radius = 6371.0 | units.km
earth.position = [0.0, 1.0, 0.0] | units.AU
earth.velocity = [2.0 * numpy.pi, -0.0001, 0.0] | units.AU / units.yr
initial_direction = math.atan((earth.velocity[0] / earth.velocity[1]))
final_direction = []
for log_eps2 in range(-9, 10, 2):
instance = Huayno(convert_nbody)
instance.initialize_code()
instance.parameters.epsilon_squared = 10.0**log_eps2 | units.AU**2
instance.particles.add_particles(particles)
instance.commit_particles()
instance.evolve_model(0.25 | units.yr)
final_direction.append(
math.atan((instance.particles[1].velocity[0] /
instance.particles[1].velocity[1])))
instance.stop()
# Small values of epsilon_squared should result in normal earth-sun dynamics: rotation of 90 degrees
self.assertAlmostEquals(abs(final_direction[0]),
abs(initial_direction + math.pi / 2.0), 2)
# Large values of epsilon_squared should result in ~ no interaction
self.assertAlmostEquals(final_direction[-1], initial_direction, 2)
# Outcome is most sensitive to epsilon_squared when epsilon_squared = d(earth, sun)^2
delta = [
abs(final_direction[i + 1] - final_direction[i])
for i in range(len(final_direction) - 1)
]
self.assertEquals(delta[len(final_direction) // 2 - 1], max(delta))
def test24(self):
print("test massless particles/ kepler integrator")
N=20
tend=2.| units.yr
numpy.random.seed(12345)
conv=nbody_system.nbody_to_si(4.| units.MSun, 5.|units.AU)
orbiters=plummer.new_plummer_model(N,conv)
sun=datamodel.Particle(mass=1.|units.MSun)
sun.position=[12.3,1.,-.2]|units.AU
sun.velocity=[10,50.,-20.]|units.kms
orbiters.mass*=0.
a0,eps0=elements(sun.mass,orbiters.x,orbiters.y,orbiters.z,
orbiters.vx,orbiters.vy,orbiters.vz)
orbiters.position+=sun.position
orbiters.velocity+=sun.velocity
pos=dict()
for inttype in [20,14]:
code=Huayno(conv)
code.parameters.inttype_parameter=inttype
code.parameters.timestep_parameter=0.1
code.particles.add_particle(sun)
orbiters2=code.particles.add_particles(orbiters).copy()
orbiters2.position-=sun.position
orbiters2.velocity-=sun.velocity
code.evolve_model(tend)
a,eps=elements(sun.mass,orbiters2.x,orbiters2.y,orbiters2.z,
orbiters2.vx,orbiters2.vy,orbiters2.vz)
da=abs((a-a0)/a0)
deps=abs(eps-eps0)/eps0
dev=numpy.where(da > 1.e-12)[0]
self.assertEqual( len(dev),0)
dev=numpy.where(deps > 1.e-12)[0]
self.assertEqual( len(dev),0)
pos[inttype]=[orbiters2.x.value_in(units.AU),orbiters2.y.value_in(units.AU),orbiters2.z.value_in(units.AU)]
self.assertAlmostEqual(pos[20][0],pos[14][0],12)
self.assertAlmostEqual(pos[20][1],pos[14][1],12)
self.assertAlmostEqual(pos[20][2],pos[14][2],12)
def test22(self):
print("Testing zero-mass test particles in Huayno, can be used for removing particles when inside recursive evolve loop")
sun_and_earth = self.new_system_of_sun_and_earth()
period = (4.0 * math.pi**2 * (1.0 | units.AU)**3 / (constants.G * sun_and_earth.total_mass())).sqrt()
convert_nbody = nbody_system.nbody_to_si(1.0 | units.MSun, 1.0 | units.AU)
huayno = Huayno(convert_nbody)
huayno.parameters.epsilon_squared = 0.0 | units.AU**2
huayno.parameters.inttype_parameter = huayno.inttypes.SHARED8
test_particle = datamodel.Particle(mass=0|units.MSun, position=[4,0,0]|units.AU, velocity=[0,0,0]|units.kms)
test_particle.vy = (constants.G * sun_and_earth.total_mass() / (4.0 | units.AU)).sqrt()
sun_and_earth.add_particle(test_particle)
huayno.particles.add_particles(sun_and_earth)
huayno.evolve_model(period)
self.assertAlmostRelativeEqual(huayno.particles[:2].x, sun_and_earth[:2].x, 13)
huayno.evolve_model(1.25 * period)
self.assertAlmostRelativeEqual(huayno.particles[1].y, sun_and_earth[1].x, 13)
huayno.evolve_model(8.0 * period)
self.assertAlmostRelativeEqual(huayno.particles.x, sun_and_earth.x, 8)
huayno.stop()
def test25(self):
print("test massless particles/ kepler integrator, smoothed")
N = 10
tend = 20. | units.yr
numpy.random.seed(12345)
conv = nbody_system.nbody_to_si(4. | units.MSun, 5. | units.AU)
orbiters = plummer.new_plummer_model(N, conv)
sun = datamodel.Particle(mass=1. | units.MSun)
sun.position = [0, 0, 0] | units.AU
sun.velocity = [0, 0, 0] | units.kms
orbiters.mass *= 0.
eps = (5. | units.AU)
e0 = energy(sun.mass, eps, orbiters)
l0 = angular_momentum(orbiters)
pos = dict()
for inttype in [20, 14]:
code = Huayno(conv)
code.parameters.inttype_parameter = inttype
code.parameters.timestep_parameter = 0.1
code.parameters.epsilon_squared = eps**2
code.particles.add_particle(sun)
orbiters2 = code.particles.add_particles(orbiters)
code.evolve_model(tend)
e1 = energy(sun.mass, eps, orbiters2)
l1 = angular_momentum(orbiters2)
de, dl = abs((e1 - e0) / e0).max(), abs((l1 - l0) / l1).max()
self.assertTrue(numpy.all(de < 1.e-8))
self.assertTrue(numpy.all(dl < 1.e-8))
pos[inttype] = [
orbiters2.x.value_in(units.AU),
orbiters2.y.value_in(units.AU),
orbiters2.z.value_in(units.AU)
]
self.assertAlmostRelativeEqual(pos[20][0], pos[14][0],
4) # still not clear why 4
self.assertAlmostRelativeEqual(pos[20][1], pos[14][1], 4)
self.assertAlmostRelativeEqual(pos[20][2], pos[14][2], 4)
def test6(self):
print("Test6: Testing Huayno parameters")
convert_nbody = nbody_system.nbody_to_si(1.0 | units.yr, 1.0 | units.AU)
instance = Huayno(convert_nbody)
(value, error) = instance.legacy_interface.get_eps2()
self.assertEqual(0, error)
self.assertEqual(0.0, value)
self.assertAlmostEqual(0.0 | units.AU**2, instance.parameters.epsilon_squared, in_units=units.AU**2)
for x in [0.01, 0.1, 0.2]:
instance.parameters.epsilon_squared = x | units.AU**2
self.assertAlmostEqual(x | units.AU**2, instance.parameters.epsilon_squared, in_units=units.AU**2)
(value, error) = instance.legacy_interface.get_time()
self.assertEqual(0, error)
self.assertEqual(0.0, value)
self.assertAlmostEqual(0.0 | units.yr, instance.parameters.begin_time, in_units=units.yr)
for x in [1.0, 10.0, 100.0]:
instance.parameters.begin_time = x | units.yr
self.assertAlmostEqual(x | units.yr, instance.parameters.begin_time, in_units=units.yr)
instance.stop()
def test5(self):
convert_nbody = nbody_system.nbody_to_si(5.0 | units.kg,
10.0 | units.m)
instance = Huayno(convert_nbody)
instance.initialize_code()
particles = datamodel.Particles(2)
self.assertEqual(len(instance.particles), 0)
particles.mass = [15.0, 30.0] | units.kg
particles.radius = [10.0, 20.0] | units.m
particles.position = [[10.0, 20.0, 30.0], [20.0, 40.0, 60.0]] | units.m
particles.velocity = [[0.0, 0.0, 0.0], [0.0, 0.0, 0.0]
] | units.m / units.s
instance.particles.add_particles(particles)
self.assertEqual(len(instance.particles), 2)
instance.set_state(1, 16 | units.kg, 20.0 | units.m, 40.0 | units.m,
60.0 | units.m, 1.0 | units.ms, 1.0 | units.ms,
1.0 | units.ms)
curr_state = instance.get_state(1)
for expected, actural in zip(
(16 | units.kg, 20.0 | units.m, 40.0 | units.m, 60.0 | units.m,
1.0 | units.ms, 1.0 | units.ms, 1.0 | units.ms, 0 | units.m),
curr_state):
self.assertAlmostRelativeEquals(actural, expected)
instance.set_state(1, 16 | units.kg, 20.0 | units.m, 40.0 | units.m,
60.0 | units.m, 1.0 | units.ms, 1.0 | units.ms,
1.0 | units.ms, 20.0 | units.m)
curr_state = instance.get_state(1)
for expected, actural in zip(
(16 | units.kg, 20.0 | units.m, 40.0 | units.m, 60.0 | units.m,
1.0 | units.ms, 1.0 | units.ms, 1.0 | units.ms, 20 | units.m),
curr_state):
self.assertAlmostRelativeEquals(actural, expected)
def timerun(N=1000,
f_bin=1.,
tend=1. | nbody_system.time,
inttype=Huayno.inttypes.HOLD_DKD,
seed=12345678,
logamin=-4):
stars = plummer_w_binaries(N=N, f_bin=f_bin, seed=seed, logamin=logamin)
code = Huayno()
code.parameters.inttype_parameter = inttype
code.parameters.timestep_parameter = 0.01
code.particles.add_particles(stars)
E0 = code.kinetic_energy + code.potential_energy
p0 = code.particles.total_momentum()
t1 = time()
code.evolve_model(tend)
t2 = time()
E = code.kinetic_energy + code.potential_energy
p = code.particles.total_momentum()
code.stop()
return t2 - t1, abs(E0 - E) / E0, p0 - p
def test2(self):
convert_nbody = nbody_system.nbody_to_si(1.0 | units.MSun,
149.5e6 | units.km)
instance = Huayno(convert_nbody)
instance.initialize_code()
instance.parameters.epsilon_squared = 0.0 | units.AU**2
stars = self.new_system_of_sun_and_earth()
earth = stars[1]
instance.particles.add_particles(stars)
for x in range(1, 2000, 10):
instance.evolve_model(x | units.day)
instance.particles.copy_values_of_all_attributes_to(stars)
stars.savepoint()
if HAS_MATPLOTLIB:
figure = pyplot.figure()
plot = figure.add_subplot(1, 1, 1)
x_points = earth.get_timeline_of_attribute("x")
y_points = earth.get_timeline_of_attribute("y")
x_points_in_AU = [t_x[1].value_in(units.AU) for t_x in x_points]
y_points_in_AU = [t_x1[1].value_in(units.AU) for t_x1 in y_points]
plot.scatter(x_points_in_AU, y_points_in_AU, color="b", marker='o')
plot.set_xlim(-1.5, 1.5)
plot.set_ylim(-1.5, 1.5)
test_results_path = self.get_path_to_results()
output_file = os.path.join(test_results_path,
"huayno-earth-sun2.svg")
figure.savefig(output_file)
instance.cleanup_code()
del instance
def test1(self):
convert_nbody = nbody_system.nbody_to_si(1.0 | units.MSun,
149.5e6 | units.km)
huayno = Huayno(convert_nbody)
huayno.initialize_code()
huayno.parameters.epsilon_squared = 0.0 | units.AU**2
stars = self.new_system_of_sun_and_earth()
earth = stars[1]
huayno.particles.add_particles(stars)
huayno.evolve_model(365.0 | units.day)
huayno.particles.copy_values_of_all_attributes_to(stars)
position_at_start = earth.position.value_in(units.AU)[0]
position_after_full_rotation = earth.position.value_in(units.AU)[0]
self.assertAlmostEqual(position_at_start, position_after_full_rotation,
6)
huayno.evolve_model(365.0 + (365.0 / 2) | units.day)
huayno.particles.copy_values_of_all_attributes_to(stars)
position_after_half_a_rotation = earth.position.value_in(units.AU)[0]
self.assertAlmostEqual(-position_at_start,
position_after_half_a_rotation, 2)
huayno.evolve_model(365.0 + (365.0 / 2) + (365.0 / 4) | units.day)
huayno.particles.copy_values_of_all_attributes_to(stars)
position_after_half_a_rotation = earth.position.value_in(units.AU)[1]
self.assertAlmostEqual(-position_at_start,
position_after_half_a_rotation, 3)
huayno.cleanup_code()
huayno.stop()
def test4(self):
convert_nbody = nbody_system.nbody_to_si(5.0 | units.kg,
10.0 | units.m)
instance = Huayno(convert_nbody)
instance.initialize_code()
particles = datamodel.Particles(2)
self.assertEqual(len(instance.particles), 0)
particles.mass = [15.0, 30.0] | units.kg
particles.radius = [10.0, 20.0] | units.m
particles.position = [[10.0, 20.0, 30.0], [20.0, 40.0, 60.0]] | units.m
particles.velocity = [[0.0, 0.0, 0.0], [0.0, 0.0, 0.0]
] | units.m / units.s
instance.particles.add_particles(particles)
self.assertEqual(len(instance.particles), 2)
instance.particles.mass = [17.0, 33.0] | units.kg
self.assertEqual(instance.get_mass(0), 17.0 | units.kg)
self.assertEqual(instance.get_mass(1), 33.0 | units.kg)
def test15(self):
particles = plummer.new_plummer_model(512)
expected_positions = None
for mode in ["cpu", "openmp", "opencl"]:
try:
instance = Huayno(mode=mode, number_of_workers=1)#, debugger="xterm")
except:
print("Running huayno with mode=", mode, " was unsuccessful.")
continue
else:
print("Running huayno with mode=", mode, "... ")
instance.initialize_code()
instance.parameters.epsilon_squared = 0.01 | nbody_system.length ** 2
instance.particles.add_particles(particles)
instance.evolve_model(0.2 | nbody_system.time)
instance.synchronize_model()
if expected_positions is None:
expected_positions = instance.particles.position
else:
self.assertAlmostRelativeEquals(expected_positions, instance.particles.position, 8)
instance.stop()
def test29(self):
instance = Huayno()
instance.parameters.epsilon_squared = 0.0 | nbody_system.length**2
particles = datamodel.Particles(2)
particles.position = ([0, 0, 0], [1, 0, 0]) | nbody_system.length
particles.velocity = ([-1, 0, 0], [2, 0, 0]) | nbody_system.speed
particles.radius = 0 | nbody_system.length
particles.mass = 0.1 | nbody_system.mass
instance.particles.add_particles(particles)
instance.stopping_conditions.out_of_box_detection.enable()
instance.parameters.stopping_conditions_out_of_box_size = 2 | nbody_system.length
instance.parameters.stopping_conditions_out_of_box_use_center_of_mass = False
instance.evolve_model(1 | nbody_system.time)
self.assertTrue(
instance.stopping_conditions.out_of_box_detection.is_set())
self.assertEqual(
len(instance.stopping_conditions.out_of_box_detection.particles(
0)), 1)
self.assertEqual(
instance.stopping_conditions.out_of_box_detection.particles(0)
[0].key, particles[1].key)
instance.stop()
def binary_with_planet_run(m1=1. | units.MSun,
m2=1. | units.MSun,
m_planet=1 | units.MJupiter,
r1=None,
r2=None,
r_planet=None,
ecc_binary=0,
P_binary=20 | units.day,
ecc_planet=0.,
P_planet=1. | units.yr,
pangle_planet=0.,
a_planet=None,
tend=100. | units.yr,
hostname=''):
dEcrit = 1.e-6
three = binary_with_planet(m1=m1,
m2=m2,
m_planet=m_planet,
r1=r1,
r2=r2,
r_planet=r_planet,
ecc_binary=ecc_binary,
P_binary=P_binary,
ecc_planet=ecc_planet,
a_planet=a_planet,
pangle_planet=pangle_planet)
convert = nbody_system.nbody_to_si(1 | units.MSun, 1 | units.AU)
code = Huayno(convert, hostname=hostname)
code.parameters.inttype_parameter = code.inttypes.SHARED10
code.parameters.timestep_parameter = .2
code.parameters.timestep = 100. | units.day
dt = 10000. | units.day
code.particles.add_particles(three)
E0 = code.potential_energy + code.kinetic_energy
a0, eps0, pangle0 = elements(three.total_mass(), code.particles.x[2],
code.particles.y[2], code.particles.z[2],
code.particles.vx[2], code.particles.vy[2],
code.particles.vz[2])
t = 0. | units.day
result = "stable"
while (t < tend - dt / 2):
t = t + dt
code.evolve_model(t)
E = code.potential_energy + code.kinetic_energy
dE = abs(((E - E0) / E0))
a, eps, pangle = elements(three.total_mass(), code.particles.x[2],
code.particles.y[2], code.particles.z[2],
code.particles.vx[2], code.particles.vy[2],
code.particles.vz[2])
if dE > dEcrit or a < 0.5 * a0 or a > 2. * a0:
result = "unstable"
if dE > dEcrit:
result = "failed"
break
code.stop()
return result, t, dE, a.in_(units.AU), eps, pangle
def evolve_triple_with_wind(M1, M2, M3, Pora, Pin_0, ain_0, aout_0, ein_0,
eout_0, t_end, nsteps, scheme, dtse_fac):
import random
from amuse.ext.solarsystem import get_position
time_framework = 0
print "Initial masses:", M1, M2, M3
t_stellar = 4.0 | units.Myr
triple = Particles(3)
triple[0].mass = M1
triple[1].mass = M2
triple[2].mass = M3
stellar = SeBa()
stellar.particles.add_particles(triple)
channel_from_stellar = stellar.particles.new_channel_to(triple)
t0 = ctime.time()
stellar.evolve_model(t_stellar)
delta_t = ctime.time() - t0
time_framework += delta_t
channel_from_stellar.copy_attributes(["mass"])
M1 = triple[0].mass
M2 = triple[1].mass
M3 = triple[2].mass
print "T=", stellar.model_time.in_(units.Myr)
print "M=", stellar.particles.mass.in_(units.MSun)
print "Masses at time T:", M1, M2, M3
# Inner binary
tmp_stars = Particles(2)
tmp_stars[0].mass = M1
tmp_stars[1].mass = M2
if Pora == 1:
ain_0 = semimajor_axis(Pin_0, M1 + M2)
else:
Pin_0 = orbital_period(ain_0, M1 + M2)
print 'ain_0 =', ain_0
print 'M1+M2 =', M1 + M2
print 'Pin_0 =', Pin_0.value_in(units.day), '[day]'
#print 'semi:', semimajor_axis(Pin_0, M1+M2).value_in(units.AU), 'AU'
#print 'period:', orbital_period(ain_0, M1+M2).value_in(units.day), '[day]'
dt = 0.1 * Pin_0
ma = 180
inc = 30
aop = 180
lon = 0
r, v = get_position(M1, M2, ein_0, ain_0, ma, inc, aop, lon, dt)
tmp_stars[1].position = r
tmp_stars[1].velocity = v
tmp_stars.move_to_center()
# Outer binary
r, v = get_position(M1 + M2, M3, eout_0, aout_0, 0, 0, 0, 0, dt)
tertiary = Particle()
tertiary.mass = M3
tertiary.position = r
tertiary.velocity = v
tmp_stars.add_particle(tertiary)
tmp_stars.move_to_center()
triple.position = tmp_stars.position
triple.velocity = tmp_stars.velocity
Mtriple = triple.mass.sum()
Pout = orbital_period(aout_0, Mtriple)
print "T=", stellar.model_time.in_(units.Myr)
print "M=", stellar.particles.mass.in_(units.MSun)
print "Pout=", Pout.in_(units.Myr)
converter = nbody_system.nbody_to_si(triple.mass.sum(), aout_0)
gravity = Huayno(converter)
gravity.particles.add_particles(triple)
channel_from_framework_to_gd = triple.new_channel_to(gravity.particles)
channel_from_gd_to_framework = gravity.particles.new_channel_to(triple)
Etot_init = gravity.kinetic_energy + gravity.potential_energy
Etot_prev = Etot_init
gravity.particles.move_to_center()
time = 0.0 | t_end.unit
ts = t_stellar + time # begin when stars have formed after 4.0 Myr years
ain, ein, aout, eout, iin, iout = get_orbital_elements_of_triple(triple)
print "Triple elements t=", time, \
"inner:", triple[0].mass, triple[1].mass, ain, ein, iin, \
"outer:", triple[2].mass, aout, eout, iout
dt_diag = t_end / float(
nsteps) # how often we want to save the generated data
t_diag = dt_diag
t = [time.value_in(units.Myr)]
smai = [ain / ain_0]
ecci = [ein / ein_0]
smao = [aout / aout_0]
ecco = [eout / eout_0]
inci = [iin]
inco = [iout]
ain = ain_0
def advance_stellar(ts, dt):
E0 = gravity.kinetic_energy + gravity.potential_energy
ts += dt
stellar.evolve_model(ts)
channel_from_stellar.copy_attributes(["mass"])
channel_from_framework_to_gd.copy_attributes(["mass"])
return ts, gravity.kinetic_energy + gravity.potential_energy - E0
def advance_stellar_with_massloss(
ts,
time_framework,
dt_massloss=15e-9 | units.Myr,
max_massloss=3e-4
| units.MSun): # Scheme 3: dt 8*10^-7, dm = 2*10^-5 (
max_massloss = 0.0 | units.MSun # massloss over full gravtiational time step massloss0
#max_massloss= 3e-6 | units.MSun # massloss over full gravtiational time step massloss1
#max_massloss= 1e-6 | units.MSun # massloss over full gravtiational time step massloss2
E0 = gravity.kinetic_energy + gravity.potential_energy
massloss = -1 | units.MSun
mass_0 = numpy.sum(stellar.particles.mass)
dt_stellar = 0 | units.Myr
niter = 0
while massloss < max_massloss:
ts += dt_massloss
dt_stellar += dt_massloss # counter for full time
niter += 1
t0 = ctime.time()
stellar.evolve_model(ts)
delta_t = ctime.time() - t0
time_framework += delta_t
massloss = 2. * (
mass_0 - numpy.sum(stellar.particles.mass)
) # massloss over full gravtiational time step is x2
channel_from_stellar.copy_attributes(["mass"])
channel_from_framework_to_gd.copy_attributes(["mass"])
print 'Tstellar:', dt_stellar, ', Total Mloss:', massloss, ' Niter:', niter
return ts, time_framework, gravity.kinetic_energy + gravity.potential_energy - E0, dt_stellar
def advance_gravity(tg, dt):
tg += dt
gravity.evolve_model(tg)
channel_from_gd_to_framework.copy()
return tg
global_time = []
global_massloss = []
global_dmdt = []
while time < t_end:
Pin = orbital_period(ain, triple[0].mass + triple[1].mass)
dt = dtse_fac * Pin
dt *= random.random(
) # time step is chosen random between 0 and 50*Pin
if scheme == 1:
ts, dE_se = advance_stellar(ts, dt)
time = advance_gravity(time, dt)
elif scheme == 2:
time = advance_gravity(time, dt)
ts, dE_se = advance_stellar(ts, dt)
elif scheme == 3:
# inital mass
mass_init = stellar.particles.mass.sum()
# perform step
ts, dE_se = advance_stellar(ts, dt / 2)
time = advance_gravity(time, dt)
ts, dE = advance_stellar(ts, dt / 2)
dE_se += dE
# add right vlaues
global_time = numpy.append(global_time, time.value_in(units.Myr))
global_massloss = numpy.append(
global_massloss,
mass_init.value_in(units.MSun) -
numpy.sum(stellar.particles.mass).value_in(units.MSun))
else: # our scheme is 4
# inital mass
mass_init = stellar.particles.mass.sum()
time_init = time.value_in(units.Myr) | units.Myr
# get optimal dt to perform a time step without losing too much mass
ts, time_framework, dE_se, dt_stellar = advance_stellar_with_massloss(
ts, time_framework)
# perform time step dt
t0 = ctime.time()
time = advance_gravity(time, dt_stellar * 2)
ts, dE = advance_stellar(ts, dt_stellar)
delta_t = ctime.time() - t0
time_framework += delta_t
dE_se += dE
# save everything
global_time = numpy.append(global_time, time.value_in(units.Myr))
global_massloss = numpy.append(
global_massloss,
mass_init.value_in(units.MSun) -
numpy.sum(stellar.particles.mass).value_in(units.MSun))
global_dmdt = numpy.append(
global_dmdt,
(mass_init.value_in(units.MSun) -
numpy.sum(stellar.particles.mass).value_in(units.MSun)) /
(time.value_in(units.Myr) - time_init.value_in(units.Myr)))
if time >= t_diag:
t_diag = time + dt_diag
Ekin = gravity.kinetic_energy
Epot = gravity.potential_energy
Etot = Ekin + Epot
dE = Etot_prev - Etot
Mtot = triple.mass.sum()
print "T=", time #,
#print "M=", Mtot, "(dM[SE]=", Mtot/Mtriple, ")",
#print "E= ", Etot, "Q= ", Ekin/Epot,
#print "dE=", (Etot_init-Etot)/Etot, "ddE=", (Etot_prev-Etot)/Etot,
#print "(dE[SE]=", dE_se/Etot, ")"
Etot_init -= dE
Etot_prev = Etot
ain, ein, aout, eout, iin, iout = get_orbital_elements_of_triple(
triple)
#print "Triple elements t=", (4|units.Myr) + time, \
# "inner:", triple[0].mass, triple[1].mass, ain, ein, \
# "outer:", triple[2].mass, aout, eout
t.append(time.value_in(units.Myr))
smai.append(ain / ain_0)
ecci.append(ein / ein_0)
smao.append(aout / aout_0)
ecco.append(eout / eout_0)
inci.append(iin)
inco.append(iout)
if eout > 1.0 or aout <= zero:
print "Binary ionized or merged"
break
pyplot.close()
data = numpy.array(zip(global_time, global_massloss, global_dmdt))
numpy.save('massloss0', data)
return t, smai, ecci, smao, ecco, inci, inco, time_framework
def main_function(number_of_stars=1000,
end_time=4.0e4 | units.yr,
steps=100,
number_of_workers=6,
animate=True,
save_animation=False,
escape=False,
Q=0.5,
D=2.6,
filename="default.mp4",
use_huayno=False,
use_tree=False):
"""
Simulates a cluster of stars with varying masses.
Input:
:param number_of_stars: Number of stars to simulate, default: 1000
:param end_time: Total time at which to stop in nbody_system.time units (I think),
default 10 | nbody_system.time
:param steps: Total number of steps to save, default: 1000
:param number_of_workers: Number of cores/threads to use, does nothing when using Huayno, default: 5
:param animate: Makes an animation of the stars at each step (size depends on star mass), default: True
:param save_animation: Saves the animation as mp4 file, default: True
:param Q: Kinectic to potential energy fraction (I think) default: 0.5
:param D: Measure of fragmentedness, must be between 1.5 and 3, default 2.6
:param filename: Determines the name of the mp4 file, default: "default.mp4"
:param use_huayno: Use alternative Huayno gravity evolver, default: False
:return: (array of position arrays at each time step, array of time at each time step)
"""
start_time = clock_time()
particles = new_cluster(number_of_stars=number_of_stars, Q=Q, D=D)
total_mass = particles.mass.sum()
convert_nbody = nbody_system.nbody_to_si(total_mass, 1.0 | units.parsec)
# Initialize gravity can use others for tests, but hermite is used
if use_huayno:
gravity = Huayno(convert_nbody,
number_of_workers=number_of_workers / 2)
elif use_tree:
gravity = BHTree(convert_nbody,
number_of_workers=1,
epsilon_squared=0.05 | nbody_system.length**2)
else:
gravity = Hermite(convert_nbody,
number_of_workers=number_of_workers / 2)
gravity.parameters.epsilon_squared = 0.05 | nbody_system.length**2
# gravity.parameters.epsilon_squared = 0.15 | nbody_system.length ** 2 # Used to be this
gravity.particles.add_particles(particles)
from_gravity_to_model = gravity.particles.new_channel_to(particles)
# particles.scale_to_standard() Cannot scale to standard if not using nbody_system units
# Initialize the Evolution
if not use_tree:
stellar_evolution = SSE(number_of_workers=number_of_workers / 2)
else:
stellar_evolution = SSE(number_of_workers=number_of_workers - 1)
stellar_evolution.particles.add_particles(particles)
from_stellar_evolution_to_model = stellar_evolution.particles.new_channel_to(
particles)
from_stellar_evolution_to_model.copy_attributes(
["mass", "luminosity", "temperature"])
# Initial time (note * end_time for correct units)
time = 0.0 * end_time
# Save initial conditions and make arrays (lists) for each step
total_energy_at_t0 = gravity.kinetic_energy + gravity.potential_energy
save_positions = [particles.position]
save_velocities = [particles.velocity]
save_masses = [particles.mass]
save_luminosities = [particles.luminosity]
save_temperatures = [particles.temperature]
times = [time]
while time < end_time:
time += end_time / steps
# Evolve gravity
gravity.evolve_model(time)
from_gravity_to_model.copy()
# Evolve stars
stellar_evolution.evolve_model(time)
from_gravity_to_model.copy()
from_stellar_evolution_to_model.copy_attributes(
["mass", "luminosity", "temperature"])
# Save data
save_positions.append(particles.position)
save_velocities.append(particles.velocity)
save_masses.append(particles.mass)
save_luminosities.append(particles.luminosity)
save_temperatures.append(particles.temperature)
times.append(time)
total_energy = gravity.kinetic_energy + gravity.potential_energy
if np.abs(
(total_energy - total_energy_at_t0) / total_energy_at_t0) > 0.001:
print(
"Warning! Total energy of the system is changing too significantly!"
)
print "Time: %.4g" % time.number
total_mass = particles.mass.sum()
print total_mass
if escape:
escaped_stars_3d, escaped_stars_2d = find_escapees(particles)
gravity.stop()
stellar_evolution.stop()
print "It took %.3g seconds clock time" % (clock_time() - start_time)
if animate:
make_animation(save_positions,
save_luminosities,
save_temperatures,
times,
save_animation=save_animation,
filename=filename)
if escape:
return save_positions[-1], save_velocities[-1], save_masses[
-1], escaped_stars_3d, escaped_stars_2d
else:
return save_positions, save_velocities
def evolve_triple_with_wind(M1, M2, M3, Pora, Pin_0, ain_0, aout_0,
ein_0, eout_0, t_end, nsteps, scheme, integrator,
t_stellar, dt_se, dtse_fac, interp):
import random
from amuse.ext.solarsystem import get_position
numpy.random.seed(42)
print("Initial masses:", M1, M2, M3)
triple = Particles(3)
triple[0].mass = M1
triple[1].mass = M2
triple[2].mass = M3
stellar = SeBa()
stellar.particles.add_particles(triple)
channel_from_stellar = stellar.particles.new_channel_to(triple)
# Evolve to t_stellar.
stellar.evolve_model(t_stellar)
channel_from_stellar.copy_attributes(["mass"])
M1 = triple[0].mass
M2 = triple[1].mass
M3 = triple[2].mass
print("t=", stellar.model_time.in_(units.Myr))
print("M=", stellar.particles.mass.in_(units.MSun))
print("R=", stellar.particles.radius.in_(units.RSun))
print("L=", stellar.particles.luminosity.in_(units.LSun))
print("T=", stellar.particles.temperature.in_(units.K))
print("Mdot=", \
-stellar.particles.wind_mass_loss_rate.in_(units.MSun/units.yr))
# Start the dynamics.
# Inner binary:
tmp_stars = Particles(2)
tmp_stars[0].mass = M1
tmp_stars[1].mass = M2
if Pora == 1:
ain_0 = semimajor_axis(Pin_0, M1+M2)
else:
Pin_0 = orbital_period(ain_0, M1+M2)
print('Pin =', Pin_0)
print('ain_0 =', ain_0)
print('M1+M2 =', M1+M2)
print('Pin_0 =', Pin_0.value_in(units.day), '[day]')
#print 'semi:', semimajor_axis(Pin_0, M1+M2).value_in(units.AU), 'AU'
#print 'period:', orbital_period(ain_0, M1+M2).value_in(units.day), '[day]'
dt_init = 0.01*Pin_0
ma = 180
inc = 60
aop = 180
lon = 0
r,v = get_position(M1, M2, ein_0, ain_0, ma, inc, aop, lon, dt_init)
tmp_stars[1].position = r
tmp_stars[1].velocity = v
tmp_stars.move_to_center()
# Outer binary:
r,v = get_position(M1+M2, M3, eout_0, aout_0, 0, 0, 0, 0, dt_init)
tertiary = Particle()
tertiary.mass = M3
tertiary.position = r
tertiary.velocity = v
tmp_stars.add_particle(tertiary)
tmp_stars.move_to_center()
triple.position = tmp_stars.position
triple.velocity = tmp_stars.velocity
Mtriple = triple.mass.sum()
Pout = orbital_period(aout_0, Mtriple)
print("T=", stellar.model_time.in_(units.Myr))
print("M=", stellar.particles.mass.in_(units.MSun))
print("Pout=", Pout.in_(units.Myr))
print('tK =', ((M1+M2)/M3)*Pout**2*(1-eout_0**2)**1.5/Pin_0)
converter = nbody_system.nbody_to_si(triple.mass.sum(), aout_0)
if integrator == 0:
gravity = Hermite(converter)
gravity.parameters.timestep_parameter = 0.01
elif integrator == 1:
gravity = SmallN(converter)
gravity.parameters.timestep_parameter = 0.01
gravity.parameters.full_unperturbed = 0
elif integrator == 2:
gravity = Huayno(converter)
gravity.parameters.inttype_parameter = 20
gravity.parameters.timestep = (1./256)*Pin_0
else:
gravity = symple(converter)
gravity.parameters.integrator = 10
#gravity.parameters.timestep_parameter = 0.
gravity.parameters.timestep = (1./128)*Pin_0
print(gravity.parameters)
gravity.particles.add_particles(triple)
channel_from_framework_to_gd = triple.new_channel_to(gravity.particles)
channel_from_gd_to_framework = gravity.particles.new_channel_to(triple)
Etot_init = gravity.kinetic_energy + gravity.potential_energy
Etot_prev = Etot_init
gravity.particles.move_to_center()
# Note: time = t_diag = 0 at the start of the dynamical integration.
dt_diag = t_end/float(nsteps)
t_diag = dt_diag
time = 0.0 | t_end.unit
t_se = t_stellar + time
print('t_end =', t_end)
print('dt_diag =', dt_diag)
ain, ein, aout, eout = get_orbital_elements_of_triple(triple)
print("Triple elements t=", time, \
"inner:", triple[0].mass, triple[1].mass, ain, ein, \
"outer:", triple[2].mass, aout, eout)
t = [time.value_in(units.Myr)]
Mtot = triple.mass.sum()
mtot = [Mtot.value_in(units.MSun)]
smai = [ain/ain_0]
ecci = [ein/ein_0]
smao = [aout/aout_0]
ecco = [eout/eout_0]
if interp:
# Create arrays of stellar times and masses for interpolation.
times = [time]
masses = [triple.mass.copy()]
while time < t_end:
time += dt_se
stellar.evolve_model(t_stellar+time)
channel_from_stellar.copy_attributes(["mass"])
times.append(time)
masses.append(triple.mass.copy())
time = 0.0 | t_end.unit
print('\ntimes:', times, '\n')
# Evolve the system.
def advance_stellar(t_se, dt):
E0 = gravity.kinetic_energy + gravity.potential_energy
t_se += dt
if interp:
t = t_se-t_stellar
i = int(t/dt_se)
mass = masses[i] + (t-times[i])*(masses[i+1]-masses[i])/dt_se
triple.mass = mass
#print 't_se =', t_se, 'masses =', mass
else:
stellar.evolve_model(t_se)
channel_from_stellar.copy_attributes(["mass"])
channel_from_framework_to_gd.copy_attributes(["mass"])
return t_se, gravity.kinetic_energy + gravity.potential_energy - E0
def advance_gravity(tg, dt):
tg += dt
gravity.evolve_model(tg)
channel_from_gd_to_framework.copy()
return tg
while time < t_end:
if scheme == 1:
# Advance to the next diagnostic time.
dE_se = zero
dt = t_diag - time
if dt > 0|dt.unit:
time = advance_gravity(time, dt)
elif scheme == 2:
# Derive dt from Pin using dtse_fac.
dt = dtse_fac*Pin_0
if time + dt > t_diag: dt = t_diag - time
if dt > 0|dt.unit:
t_se, dE_se = advance_stellar(t_se, dt)
time = advance_gravity(time, dt)
elif scheme == 3:
# Derive dt from Pin using dtse_fac.
dt = dtse_fac*Pin_0
if time + dt > t_diag: dt = t_diag - time
if dt > 0|dt.unit:
time = advance_gravity(time, dt)
t_se, dE_se = advance_stellar(t_se, dt)
elif scheme == 4:
# Derive dt from Pin using dtse_fac.
dt = dtse_fac*Pin_0
if time + dt > t_diag: dt = t_diag - time
if dt > 0|dt.unit:
t_se, dE_se = advance_stellar(t_se, 0.5*dt)
time = advance_gravity(time, dt)
t_se, dE_se2 = advance_stellar(t_se, 0.5*dt)
dE_se += dE_se2
elif scheme == 5:
# Use the specified dt_se.
dE_se = zero
dt = dt_se
if time + dt > t_diag: dt = t_diag - time
if dt > 0|dt.unit:
# For use with symple only: set up average mass loss.
channel_from_stellar.copy_attributes(["mass"])
m0 = triple.mass.copy()
stellar.evolve_model(t_se+dt)
channel_from_stellar.copy_attributes(["mass"])
t_se = stellar.model_time
m1 = triple.mass
dmdt = (m1-m0)/dt
for i in range(len(dmdt)):
gravity.set_dmdt(i, dmdt[i])
time = advance_gravity(time, dt)
else:
print('unknown option')
sys.exit(0)
if time >= t_diag:
t_diag = time + dt_diag
Ekin = gravity.kinetic_energy
Epot = gravity.potential_energy
Etot = Ekin + Epot
dE = Etot_prev - Etot
Mtot = triple.mass.sum()
print("T=", time, end=' ')
print("M=", Mtot, "(dM[SE]=", Mtot/Mtriple, ")", end=' ')
print("E= ", Etot, "Q= ", Ekin/Epot, end=' ')
print("dE=", (Etot_init-Etot)/Etot, "ddE=", (Etot_prev-Etot)/Etot, end=' ')
print("(dE[SE]=", dE_se/Etot, ")")
Etot_init -= dE
Etot_prev = Etot
ain, ein, aout, eout = get_orbital_elements_of_triple(triple)
print("Triple elements t=", t_stellar + time, \
"inner:", triple[0].mass, triple[1].mass, ain, ein, \
"outer:", triple[2].mass, aout, eout)
t.append(time.value_in(units.yr))
mtot.append(Mtot.value_in(units.MSun))
smai.append(ain/ain_0)
ecci.append(ein/ein_0)
smao.append(aout/aout_0)
ecco.append(eout/eout_0)
if eout > 1 or aout <= zero:
print("Binary ionized or merged")
break
gravity.stop()
stellar.stop()
return t, mtot, smai, ecci, smao, ecco
def evolution_of_the_cluster(self, cluster):
'''
Function that makes de cluster evolution.
input: cluster -> defined in an inertial frame (centered at the Galactic center)
steps in this function:
1. From cluster, another cluster is defined in a rotating frame
2. The gravity code is initialized
3. The stellar evolution is initialized
4. the Galaxy model is constructed
5. The Galaxy and the cluster in the rotating frame are coupled via the Rotating Bridge
6. The evolution of the system is made
7. the cluster properties are transformed back to the inertial frame
'''
cluster_in_rotating_frame = self.creation_cluster_in_rotating_frame(
cluster)
# N body code
epsilon = self.softening(cluster)
convert_nbody = nbody_system.nbody_to_si(cluster.mass.sum(),
cluster.virial_radius())
gravity = Huayno(convert_nbody)
gravity.parameters.timestep = self.dt_bridge / 3.
gravity.particles.add_particles(cluster_in_rotating_frame)
gravity.parameters.epsilon_squared = epsilon**2
channel_from_gravity_to_rotating_cluster = gravity.particles.new_channel_to(
cluster_in_rotating_frame)
channel_from_rotating_cluster_to_gravity = cluster_in_rotating_frame.new_channel_to(
gravity.particles)
#stellar evolution code
se = SeBa()
se.particles.add_particles(cluster_in_rotating_frame)
channel_from_rotating_cluster_to_se = cluster_in_rotating_frame.new_channel_to(
se.particles)
channel_from_se_to_rotating_cluster = se.particles.new_channel_to(
cluster_in_rotating_frame)
# Galaxy model and Rotating bridge
MW = self.galactic_model()
system = Rotating_Bridge(self.omega_system,
timestep=self.dt_bridge,
verbose=False,
method=self.method)
system.add_system(gravity, (MW, ), False)
system.add_system(MW, (), False)
X = []
Y = []
T = []
#Cluster evolution
while (self.time <= self.t_end - self.dt_bridge / 2):
self.time += self.dt_bridge
system.evolve_model(self.time)
se.evolve_model(self.time)
channel_from_gravity_to_rotating_cluster.copy_attributes(
['x', 'y', 'z', 'vx', 'vy', 'vz'])
channel_from_se_to_rotating_cluster.copy_attributes([
'mass', 'radius', 'luminosity', 'age', 'temperature',
'stellar_type'
])
channel_from_rotating_cluster_to_gravity.copy_attributes(['mass'])
self.from_noinertial_to_cluster_in_inertial_frame(
cluster_in_rotating_frame, cluster)
time = self.time.value_in(units.Myr)
cm = cluster.center_of_mass()
# write data
if ((time == 2) or (time == 50) or (time == 100) or (time == 150)):
X.append((cluster.x - cm[0]).value_in(units.kpc))
Y.append((cluster.y - cm[1]).value_in(units.kpc))
T.append(time)
gravity.stop()
se.stop()
return T, X, Y
def test_run():
three = binary_with_planet(m1=0.6897 | units.MSun,
m2=0.20255 | units.MSun,
m_planet=0.333 | units.MJupiter,
r1=0.6489 | units.RSun,
r2=0.22623 | units.RSun,
r_planet=0.754 | units.RJupiter,
ecc_binary=0.15944,
P_binary=41.08 | units.day,
ecc_planet=0.00685,
a_planet=.7048 | units.AU,
pangle_planet=0.)
convert = nbody_system.nbody_to_si(1 | units.MSun, 1 | units.AU)
code = Huayno(convert)
code.parameters.inttype_parameter = code.inttypes.SHARED4
code.parameters.timestep_parameter = 0.1
# tend=100. | units.yr
tend = 100. | units.day
snapfreq = 1
dt = 10. | units.day
# dt=convert.to_si( 1. | nbody_system.time).in_(units.day)
code.particles.add_particles(three)
x = AdaptingVectorQuantity()
y = AdaptingVectorQuantity()
z = AdaptingVectorQuantity()
vx = AdaptingVectorQuantity()
vy = AdaptingVectorQuantity()
vz = AdaptingVectorQuantity()
x.append(code.particles.x)
y.append(code.particles.y)
z.append(code.particles.z)
vx.append(code.particles.vx)
vy.append(code.particles.vy)
vz.append(code.particles.vz)
ts = [0.]
E0 = code.potential_energy + code.kinetic_energy
dE = [1.e-14]
t = 0. | units.day
i = 0
while (t < tend - dt / 2):
i += 1
t = t + dt
if i % snapfreq == 0:
print t
ts.append(t.value_in(units.day))
code.evolve_model(t)
x.append(code.particles.x)
y.append(code.particles.y)
z.append(code.particles.z)
vx.append(code.particles.vx)
vy.append(code.particles.vy)
vz.append(code.particles.vz)
E = code.potential_energy + code.kinetic_energy
dE.append(abs(((E - E0) / E0)))
code.stop()
a, eps, pangle = elements(three.total_mass(), x[:, 2], y[:, 2], z[:, 2],
vx[:, 2], vy[:, 2], vz[:, 2])
x = x.value_in(units.AU)
y = y.value_in(units.AU)
a = a.value_in(units.AU)
eps = eps
print a[-1], eps[-1], pangle[-1]
f = pyplot.figure(figsize=(8, 8))
pyplot.plot(x[:, 0], y[:, 0], 'r.')
pyplot.plot(x[:, 1], y[:, 1], 'g.')
pyplot.plot(x[:, 2], y[:, 2], 'b.')
pyplot.xlim(-3, 3)
pyplot.ylim(-3, 3)
pyplot.xlabel('AU')
pyplot.savefig('three_16b.eps')
f = pyplot.figure(figsize=(8, 8))
pyplot.semilogy(ts, dE, 'g.')
pyplot.xlabel('time (day)')
pyplot.ylabel('dE/E0')
pyplot.savefig('three_16b_eerr.eps')
f = pyplot.figure(figsize=(8, 8))
pyplot.plot(ts, a, 'g.')
pyplot.xlabel('time (day)')
pyplot.ylabel('a (AU)')
pyplot.savefig('three_16b_a.eps')
f = pyplot.figure(figsize=(8, 8))
pyplot.plot(ts, eps, 'g.')
pyplot.xlabel('time (day)')
pyplot.ylabel('eccentricity')
pyplot.savefig('three_16b_ecc.eps')
f = pyplot.figure(figsize=(8, 8))
pyplot.plot(ts, pangle, 'g.')
pyplot.xlabel('time (day)')
pyplot.ylabel('long. of periapsis')
pyplot.savefig('three_16b_pangle.eps')
def get_huayno(converter):
instance = Huayno(converter)
instance.initialize_code()
instance.parameters.set_defaults()
return instance
def _run_collision_with_integrator(self, inttype_parameter):
particles = datamodel.Particles(7)
particles.mass = 0.001 | nbody_system.mass
particles.radius = 0.01 | nbody_system.length
particles.x = [-101.0, -100.0, -0.5, 0.5, 100.0, 101.0, 104.0
] | nbody_system.length
particles.y = 0 | nbody_system.length
particles.z = 0 | nbody_system.length
particles.velocity = [[2, 0, 0], [-2, 0, 0]
] * 3 + [[-4, 0, 0]] | nbody_system.speed
instance = Huayno()
instance.parameters.inttype_parameter = inttype_parameter
instance.particles.add_particles(particles)
collisions = instance.stopping_conditions.collision_detection
collisions.enable()
instance.evolve_model(1.0 | nbody_system.time)
self.assertTrue(collisions.is_set())
self.assertTrue(instance.model_time < 0.5 | nbody_system.time)
self.assertEquals(len(collisions.particles(0)), 3)
self.assertEquals(len(collisions.particles(1)), 3)
self.assertEquals(
len(particles - collisions.particles(0) - collisions.particles(1)),
1)
self.assertEquals(
abs(collisions.particles(0).x - collisions.particles(1).x) <=
(collisions.particles(0).radius + collisions.particles(1).radius),
[True, True, True])
sticky_merged = datamodel.Particles(len(collisions.particles(0)))
sticky_merged.mass = collisions.particles(
0).mass + collisions.particles(1).mass
sticky_merged.radius = collisions.particles(0).radius
for p1, p2, merged in zip(collisions.particles(0),
collisions.particles(1), sticky_merged):
merged.position = (p1 + p2).center_of_mass()
merged.velocity = (p1 + p2).center_of_mass_velocity()
print instance.model_time
print instance.particles
instance.particles.remove_particles(
collisions.particles(0) + collisions.particles(1))
instance.particles.add_particles(sticky_merged)
instance.evolve_model(1.0 | nbody_system.time)
print
print instance.model_time
print instance.particles
self.assertTrue(collisions.is_set())
self.assertTrue(instance.model_time < 1.0 | nbody_system.time)
self.assertEquals(len(collisions.particles(0)), 1)
self.assertEquals(len(collisions.particles(1)), 1)
self.assertEquals(
len(instance.particles - collisions.particles(0) -
collisions.particles(1)), 2)
self.assertEquals(
abs(collisions.particles(0).x - collisions.particles(1).x) <=
(collisions.particles(0).radius + collisions.particles(1).radius),
[True])
instance.stop()
