def test2(self):
seed(1)
particles=new_plummer_model(10000)
instance = Agama(type="Multipole", particles=particles)
result=instance.get_potential_at_point(
0.|generic_unit_system.length,
0.|generic_unit_system.length,
0.|generic_unit_system.length,
0.|generic_unit_system.length)
self.assertLess(abs(result/(-16./3/3.1416|
generic_unit_system.length**2/generic_unit_system.time**2) - 1), 0.04)
scaleM=1234|units.MSun
scaleR=5.6 |units.parsec
converter=nbody_system.nbody_to_si(scaleM,scaleR)
particles=new_plummer_model(20000, convert_nbody=converter)
instance = Agama(converter, type="Multipole", particles=particles)
x=3.|units.parsec
y=4.|units.parsec
z=5.|units.parsec
r=(x*x+y*y+z*z)**0.5
result=instance.get_gravity_at_point(0|units.parsec, x, y, z)
expected=-constants.G*scaleM/(r*r+(3*3.1416/16*scaleR)**2)**1.5*x
self.assertLess(abs(result[0]/expected-1), 0.03)
self.assertLess(abs(result[2]/result[0]-z/x), 0.03)
instance.stop()
def test1(self):
M=10.
a=2.
x=1.
y=2.
z=3.
r=(x*x+y*y+z*z)**0.5
instance = Agama(type="Dehnen", mass=M|generic_unit_system.mass, scaleRadius=a|generic_unit_system.length)
result=instance.get_potential_at_point(
0.|generic_unit_system.length,
x |generic_unit_system.length,
y |generic_unit_system.length,
z |generic_unit_system.length)
self.assertAlmostEqual(result.value_in(generic_unit_system.length**2/generic_unit_system.time**2), -M/(r+a), places=14)
result=instance.get_gravity_at_point(
0.|generic_unit_system.length,
x |generic_unit_system.length,
y |generic_unit_system.length,
z |generic_unit_system.length)
self.assertAlmostEqual(result[0].value_in(generic_unit_system.length/generic_unit_system.time**2), -M/(r+a)**2 * x/r, places=14)
self.assertAlmostEqual(result[0],result[2]/3, places=14)
scaleM=2.345678|units.MSun
scalea=7.654321|units.parsec
converter=nbody_system.nbody_to_si(scaleM, scalea)
instance = Agama(converter, type="Dehnen", mass=M*scaleM, scaleradius=a*scalea)
result=instance.get_gravity_at_point(
0.|generic_unit_system.length, x*scalea, y*scalea, z*scalea)
scale=M/(r+a)**2 *scaleM/scalea**2*constants.G
self.assertAlmostEqual(result[0], scale * x/r, places=10)
instance.stop()
def test1(self):
M=10.
a=2.
x=1.
y=2.
z=3.
r=(x*x+y*y+z*z)**0.5
instance = Agama(type="Dehnen",
mass=M|generic_unit_system.mass, scaleRadius=a|generic_unit_system.length)
result=instance.get_potential_at_point(
0.|generic_unit_system.length,
x |generic_unit_system.length,
y |generic_unit_system.length,
z |generic_unit_system.length)
self.assertAlmostEqual(result.value_in(
generic_unit_system.length**2/generic_unit_system.time**2), -M/(r+a), places=14)
result=instance.get_gravity_at_point(
0.|generic_unit_system.length,
x |generic_unit_system.length,
y |generic_unit_system.length,
z |generic_unit_system.length)
self.assertAlmostEqual(result[0].value_in(
generic_unit_system.length/generic_unit_system.time**2), -M/(r+a)**2 * x/r, places=14)
self.assertAlmostEqual(result[0],result[2]/3, places=14)
scaleM=2.345678|units.MSun
scalea=7.654321|units.parsec
converter=nbody_system.nbody_to_si(scaleM, scalea)
instance = Agama(converter, type="Dehnen", mass=M*scaleM, scaleradius=a*scalea)
result=instance.get_gravity_at_point(
0.|generic_unit_system.length, x*scalea, y*scalea, z*scalea)
scale=M/(r+a)**2 *scaleM/scalea**2*constants.G
self.assertAlmostEqual(result[0], scale * x/r, places=10)
instance.stop()
def test2(self):
particles=new_plummer_model(10000)
instance = Agama(type="Multipole", points=particles)
result=instance.get_potential_at_point(
0.|generic_unit_system.length,
0.|generic_unit_system.length,
0.|generic_unit_system.length,
0.|generic_unit_system.length)
self.assertLess(abs(result/(-16./3/3.1416| generic_unit_system.length**2/generic_unit_system.time**2) - 1), 0.04)
scaleM=1234|units.MSun
scaleR=5.6 |units.parsec
converter=nbody_system.nbody_to_si(scaleM,scaleR)
particles=new_plummer_model(20000, convert_nbody=converter)
instance = Agama(converter, type="Multipole", points=particles)
x=3.|units.parsec
y=4.|units.parsec
z=5.|units.parsec
r=(x*x+y*y+z*z)**0.5
result=instance.get_gravity_at_point(0|units.parsec, x, y, z)
expected=-constants.G*scaleM/(r*r+(3*3.1416/16*scaleR)**2)**1.5*x
self.assertLess(abs(result[0]/expected-1), 0.03)
self.assertLess(abs(result[2]/result[0]-z/x), 0.03)
