def test3(self):
print("Testing virial radius of an Evrard model.")
target_number_of_particles = 100
gas_parts = new_evrard_gas_sphere(target_number_of_particles,
do_scale=True,
seed=1234)
self.assertAlmostEqual(gas_parts.virial_radius(), 1.00 | nbody.length)
def run_evrard(
hydro_legacy_codes,
number_of_particles,
random_seed=None,
name_of_the_figure="evrard_collapse_test.png"):
print(
"\nThe spherical collapse of an initially-cold adiabatic gas cloud,\n",
"consisting of ",
str(number_of_particles),
"particles will be simulated...\n"
)
# (3 natural timescales)
t_end = 3.0 * convert_nbody_units.to_si(1.0 | nbody_system.time)
print "Evolving to (3 natural timescales): ", t_end.as_quantity_in(
units.Myr)
n_steps = 100
gas = new_evrard_gas_sphere(
number_of_particles,
convert_nbody_units,
do_scale=True,
seed=random_seed)
gas.h_smooth = 0.01 | units.kpc
times = [] | units.Myr
kinetic_energies = []
potential_energies = []
thermal_energies = []
for hydro_legacy_code in hydro_legacy_codes:
try:
hydro_legacy_code.parameters.timestep = t_end / n_steps
except Exception as exc:
if "parameter is read-only" not in str(exc):
raise
hydro_legacy_code.gas_particles.add_particles(gas)
kinetic_energies.append([] | units.J)
potential_energies.append([] | units.J)
thermal_energies.append([] | units.J)
for time in [i*t_end/n_steps for i in range(1, n_steps+1)]:
for i, hydro_legacy_code in enumerate(hydro_legacy_codes):
hydro_legacy_code.evolve_model(time)
kinetic_energies[i].append(hydro_legacy_code.kinetic_energy)
potential_energies[i].append(hydro_legacy_code.potential_energy)
thermal_energies[i].append(hydro_legacy_code.thermal_energy)
times.append(time)
for hydro_legacy_code in hydro_legacy_codes:
hydro_legacy_code.stop()
energy_plot(times, kinetic_energies, potential_energies,
thermal_energies, name_of_the_figure)
print "All done!\n"
def test2(self):
print "Testing properties of an Evrard model."
target_number_of_particles = 1000
gas_parts = new_evrard_gas_sphere(target_number_of_particles, do_scale=True, seed=1234)
self.assertEquals(len(gas_parts), 1000)
self.assertAlmostEqual(gas_parts.kinetic_energy(), 0.00 | nbody.energy)
self.assertAlmostEqual(gas_parts.potential_energy(G=nbody.G), -0.50 | nbody.energy)
self.assertAlmostEqual(gas_parts.center_of_mass(), [0,0,0] | nbody.length)
self.assertAlmostEqual(gas_parts.center_of_mass_velocity(), [0,0,0] | nbody.speed)
self.assertAlmostEqual(gas_parts.mass.sum(), 1.00 | nbody.mass)
def run_evrard(hydro_legacy_codes,
number_of_particles,
random_seed=None,
name_of_the_figure="evrard_collapse_test.png"):
print(
"\nThe spherical collapse of an initially-cold adiabatic gas cloud,\n",
"consisting of ", str(number_of_particles),
"particles will be simulated...\n")
# (3 natural timescales)
t_end = 3.0 * convert_nbody_units.to_si(1.0 | nbody_system.time)
print("Evolving to (3 natural timescales): ",
t_end.as_quantity_in(units.Myr))
n_steps = 100
gas = new_evrard_gas_sphere(number_of_particles,
convert_nbody_units,
do_scale=True,
seed=random_seed)
gas.h_smooth = 0.01 | units.kpc
times = [] | units.Myr
kinetic_energies = []
potential_energies = []
thermal_energies = []
for hydro_legacy_code in hydro_legacy_codes:
try:
hydro_legacy_code.parameters.timestep = t_end / n_steps
except Exception as exc:
if "parameter is read-only" not in str(exc):
raise
hydro_legacy_code.gas_particles.add_particles(gas)
kinetic_energies.append([] | units.J)
potential_energies.append([] | units.J)
thermal_energies.append([] | units.J)
for time in [i * t_end / n_steps for i in range(1, n_steps + 1)]:
for i, hydro_legacy_code in enumerate(hydro_legacy_codes):
hydro_legacy_code.evolve_model(time)
kinetic_energies[i].append(hydro_legacy_code.kinetic_energy)
potential_energies[i].append(hydro_legacy_code.potential_energy)
thermal_energies[i].append(hydro_legacy_code.thermal_energy)
times.append(time)
for hydro_legacy_code in hydro_legacy_codes:
hydro_legacy_code.stop()
energy_plot(times, kinetic_energies, potential_energies, thermal_energies,
name_of_the_figure)
print("All done!\n")
def test3(self):
print("Demonstrate new_sink_particles usage (using Gadget2)")
UnitLength = 1.0 | units.kpc
UnitMass = 1.0e10 | units.MSun
UnitVelocity = 1.0 | units.km / units.s
convert_nbody = nbody_system.nbody_to_si(UnitLength, UnitMass)
converter = ConvertBetweenGenericAndSiUnits(UnitLength, UnitMass, UnitVelocity)
number_gas_particles = 1000
gas = new_evrard_gas_sphere(number_gas_particles, convert_nbody, do_scale=True, seed=12345)
sph_code = Gadget2(converter)
sph_code.initialize_code()
sph_code.parameters.stopping_condition_maximum_density = 10 * UnitMass / UnitLength**3
sph_code.gas_particles.add_particles(gas)
self.assertIsOfOrder(max(sph_code.gas_particles.density), UnitMass / UnitLength**3)
density_limit_detection = sph_code.stopping_conditions.density_limit_detection
density_limit_detection.enable()
sph_code.evolve_model(10.0 | units.Myr)
self.assertTrue(density_limit_detection.is_set())
self.assertTrue(sph_code.model_time < 10.0 | units.Myr)
print("density_limit exceeded at t =", sph_code.model_time.as_quantity_in(units.Myr))
self.assertEqual(len(density_limit_detection.particles()), 1)
self.assertTrue(density_limit_detection.particles().density >
10 * UnitMass / UnitLength**3)
clumps = density_limit_detection.particles().copy()
sph_code.gas_particles.remove_particles(clumps)
clumps_in_code = sph_code.dm_particles.add_particles(clumps)
sinks = new_sink_particles(clumps_in_code,looping_over=self.looping_over)
self.assertEqual(sinks.sink_radius, clumps.radius)
self.assertAlmostRelativeEqual(sinks.mass, UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sinks.position, clumps.position, 10)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 1)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
self.assertEqual(set(sinks.get_attribute_names_defined_in_store()) - set(["sink_radius","lx","ly","lz"]),
set(sph_code.particles.get_attribute_names_defined_in_store()))
sinks.accrete(sph_code.gas_particles)
self.assertAlmostRelativeEqual(sinks.mass, 3 * UnitMass / number_gas_particles, 10)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 3)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
sinks.accrete(sph_code.particles) # Nothing happens: gas already gone, and cannot accrete itself
self.assertAlmostRelativeEqual(sinks.mass, 3 * UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
steps = 0
while True:
sph_code.evolve_model(sph_code.model_time + (0.1 | units.Myr))
sinks.sink_radius = 4 * clumps_in_code.radius
sinks.accrete(sph_code.gas_particles)
steps += 1
if density_limit_detection.is_set():
break
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 7)
self.assertAlmostRelativeEqual(sinks.mass, 7 * UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
self.assertTrue(density_limit_detection.is_set())
self.assertEqual(steps, 5)
self.assertTrue(sph_code.model_time < 10.0 | units.Myr)
print("density_limit exceeded at t =", sph_code.model_time.as_quantity_in(units.Myr))
self.assertEqual(len(density_limit_detection.particles()), 5)
self.assertTrue((density_limit_detection.particles().density >
10 * UnitMass / UnitLength**3).all())
clumps = density_limit_detection.particles().copy()
sph_code.gas_particles.remove_particles(clumps)
clumps_in_code = sph_code.dm_particles.add_particles(clumps)
sinks.add_sinks(clumps_in_code, sink_radius=0.1|units.kpc)
self.assertEqual(sinks[1:].sink_radius, 0.1 | units.kpc)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 12)
self.assertAlmostRelativeEqual(sinks.mass[1:], UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sinks.position[1:], clumps.position, 10)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
sinks.accrete(sph_code.gas_particles)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 66)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass().as_quantity_in(units.MSun), UnitMass, 10)
self.assertAlmostRelativeEqual(sinks.mass, [7.0, 13.0, 15.0, 9.0, 11.0, 11.0] * UnitMass / number_gas_particles, 10)
def test1(self):
print("First test: making an Evrard gas sphere model.")
target_number_of_particles = 1000
gas_parts = new_evrard_gas_sphere(target_number_of_particles,
seed=1234)
self.assertEqual(len(gas_parts), 1000)
def test3(self):
print "Demonstrate new_sink_particles usage (using Gadget2)"
UnitLength = 1.0 | units.kpc
UnitMass = 1.0e10 | units.MSun
UnitVelocity = 1.0 | units.km / units.s
convert_nbody = nbody_system.nbody_to_si(UnitLength, UnitMass)
converter = ConvertBetweenGenericAndSiUnits(UnitLength, UnitMass, UnitVelocity)
number_gas_particles = 1000
gas = new_evrard_gas_sphere(number_gas_particles, convert_nbody, do_scale=True, seed=12345)
sph_code = Gadget2(converter)
sph_code.initialize_code()
sph_code.parameters.stopping_condition_maximum_density = 10 * UnitMass / UnitLength**3
sph_code.gas_particles.add_particles(gas)
self.assertIsOfOrder(max(sph_code.gas_particles.density), UnitMass / UnitLength**3)
density_limit_detection = sph_code.stopping_conditions.density_limit_detection
density_limit_detection.enable()
sph_code.evolve_model(10.0 | units.Myr)
self.assertTrue(density_limit_detection.is_set())
self.assertTrue(sph_code.model_time < 10.0 | units.Myr)
print "density_limit exceeded at t =", sph_code.model_time.as_quantity_in(units.Myr)
self.assertEquals(len(density_limit_detection.particles()), 1)
self.assertTrue(density_limit_detection.particles().density >
10 * UnitMass / UnitLength**3)
clumps = density_limit_detection.particles().copy()
sph_code.gas_particles.remove_particles(clumps)
clumps_in_code = sph_code.dm_particles.add_particles(clumps)
sinks = new_sink_particles(clumps_in_code,looping_over=self.looping_over)
self.assertEqual(sinks.sink_radius, clumps.radius)
self.assertAlmostRelativeEqual(sinks.mass, UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sinks.position, clumps.position, 10)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 1)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
self.assertEqual(set(sinks.get_attribute_names_defined_in_store()) - set(["sink_radius","lx","ly","lz"]),
set(sph_code.particles.get_attribute_names_defined_in_store()))
sinks.accrete(sph_code.gas_particles)
self.assertAlmostRelativeEqual(sinks.mass, 3 * UnitMass / number_gas_particles, 10)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 3)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
sinks.accrete(sph_code.particles) # Nothing happens: gas already gone, and cannot accrete itself
self.assertAlmostRelativeEqual(sinks.mass, 3 * UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
steps = 0
while True:
sph_code.evolve_model(sph_code.model_time + (0.1 | units.Myr))
sinks.sink_radius = 4 * clumps_in_code.radius
sinks.accrete(sph_code.gas_particles)
steps += 1
if density_limit_detection.is_set():
break
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 7)
self.assertAlmostRelativeEqual(sinks.mass, 7 * UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
self.assertTrue(density_limit_detection.is_set())
self.assertEqual(steps, 5)
self.assertTrue(sph_code.model_time < 10.0 | units.Myr)
print "density_limit exceeded at t =", sph_code.model_time.as_quantity_in(units.Myr)
self.assertEquals(len(density_limit_detection.particles()), 5)
self.assertTrue((density_limit_detection.particles().density >
10 * UnitMass / UnitLength**3).all())
clumps = density_limit_detection.particles().copy()
sph_code.gas_particles.remove_particles(clumps)
clumps_in_code = sph_code.dm_particles.add_particles(clumps)
sinks.add_sinks(clumps_in_code, sink_radius=0.1|units.kpc)
self.assertEqual(sinks[1:].sink_radius, 0.1 | units.kpc)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 12)
self.assertAlmostRelativeEqual(sinks.mass[1:], UnitMass / number_gas_particles, 10)
self.assertAlmostRelativeEqual(sinks.position[1:], clumps.position, 10)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass(), UnitMass, 10)
self.assertAlmostRelativeEqual(sph_code.gas_particles.total_mass(), UnitMass - sinks.total_mass(), 10)
sinks.accrete(sph_code.gas_particles)
self.assertEqual(len(sph_code.gas_particles), number_gas_particles - 66)
self.assertAlmostRelativeEqual(sph_code.particles.total_mass().as_quantity_in(units.MSun), UnitMass, 10)
self.assertAlmostRelativeEqual(sinks.mass, [7.0, 13.0, 15.0, 9.0, 11.0, 11.0] * UnitMass / number_gas_particles, 10)
def test1(self):
print "First test: making an Evrard gas sphere model."
target_number_of_particles = 1000
gas_parts = new_evrard_gas_sphere(target_number_of_particles, seed=1234)
self.assertEquals(len(gas_parts), 1000)
def test3(self):
print "Testing virial radius of an Evrard model."
target_number_of_particles = 100
gas_parts = new_evrard_gas_sphere(target_number_of_particles, do_scale=True, seed=1234)
self.assertAlmostEqual(gas_parts.virial_radius(), 1.00 | nbody.length)