def test15(self):
particles = datamodel.Particles(2)
particles.x = [0.0,10.0] | nbody_system.length
particles.y = 0.0 | nbody_system.length
particles.z = 0.0 | nbody_system.length
particles.vx = 0.0 | nbody_system.speed
particles.vy = 0.0 | nbody_system.speed
particles.vz = 0.0 | nbody_system.speed
particles.mass = 1.0 | nbody_system.mass
instance = Hermite()
instance.particles.add_particles(particles)
instance.commit_particles()
self.assertEquals(instance.particles[0].radius, 0.0 | nbody_system.length)
p = datamodel.Particle(
x = 1.0 | nbody_system.length,
y = 2.0 | nbody_system.length,
z = 3.0 | nbody_system.length,
vx = 1.0 | nbody_system.speed,
vy = 2.0 | nbody_system.speed,
vz = 3.0 | nbody_system.speed,
mass = 1.0 | nbody_system.mass,
radius = 4.0 | nbody_system.length,
)
instance.particles.add_particle(p)
self.assertEquals(instance.particles[0].radius, 0.0 | nbody_system.length)
self.assertEquals(instance.particles[1].radius, 0.0 | nbody_system.length)
self.assertEquals(instance.particles[2].radius, 4.0 | nbody_system.length)
instance.stop()
def test18(self):
particles = datamodel.Particles(2)
particles.x = [0.0,1.0] | nbody_system.length
particles.y = 0.0 | nbody_system.length
particles.z = 0.0 | nbody_system.length
particles.vx = 0.0 | nbody_system.speed
particles.vy = 0.0 | nbody_system.speed
particles.vz = 0.0 | nbody_system.speed
particles.mass = 1.0 | nbody_system.mass
instance = Hermite()
instance.particles.add_particles(particles)
instance.commit_particles()
self.assertEquals(instance.particles[0].radius, 0.0 | nbody_system.length)
instance.parameters.end_time_accuracy_factor = 1.0
instance.evolve_model(0.1 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.10563767746 |nbody_system.time, 5)
instance.parameters.end_time_accuracy_factor = -1.0
instance.evolve_model(0.3 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.266758127609 |nbody_system.time, 5)
instance.parameters.end_time_accuracy_factor = 0.0
instance.evolve_model(0.4 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.4 |nbody_system.time, 6)
instance.parameters.end_time_accuracy_factor = -0.5
instance.evolve_model(0.5 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.48974930698 |nbody_system.time, 6)
instance.parameters.end_time_accuracy_factor = +0.5
instance.evolve_model(0.6 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.6042733579 |nbody_system.time, 6)
instance.stop()
def test15(self):
particles = datamodel.Particles(2)
particles.x = [0.0, 10.0] | nbody_system.length
particles.y = 0.0 | nbody_system.length
particles.z = 0.0 | nbody_system.length
particles.vx = 0.0 | nbody_system.speed
particles.vy = 0.0 | nbody_system.speed
particles.vz = 0.0 | nbody_system.speed
particles.mass = 1.0 | nbody_system.mass
instance = Hermite()
instance.particles.add_particles(particles)
instance.commit_particles()
self.assertEquals(instance.particles[0].radius,
0.0 | nbody_system.length)
p = datamodel.Particle(
x=1.0 | nbody_system.length,
y=2.0 | nbody_system.length,
z=3.0 | nbody_system.length,
vx=1.0 | nbody_system.speed,
vy=2.0 | nbody_system.speed,
vz=3.0 | nbody_system.speed,
mass=1.0 | nbody_system.mass,
radius=4.0 | nbody_system.length,
)
instance.particles.add_particle(p)
self.assertEquals(instance.particles[0].radius,
0.0 | nbody_system.length)
self.assertEquals(instance.particles[1].radius,
0.0 | nbody_system.length)
self.assertEquals(instance.particles[2].radius,
4.0 | nbody_system.length)
instance.stop()
def test18(self):
particles = datamodel.Particles(2)
particles.x = [0.0,1.0] | nbody_system.length
particles.y = 0.0 | nbody_system.length
particles.z = 0.0 | nbody_system.length
particles.vx = 0.0 | nbody_system.speed
particles.vy = 0.0 | nbody_system.speed
particles.vz = 0.0 | nbody_system.speed
particles.mass = 1.0 | nbody_system.mass
instance = Hermite()
instance.particles.add_particles(particles)
instance.commit_particles()
self.assertEquals(instance.particles[0].radius, 0.0 | nbody_system.length)
instance.parameters.end_time_accuracy_factor = 1.0
instance.evolve_model(0.1 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.10563767746 |nbody_system.time, 5)
instance.parameters.end_time_accuracy_factor = -1.0
instance.evolve_model(0.3 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.266758127609 |nbody_system.time, 5)
instance.parameters.end_time_accuracy_factor = 0.0
instance.evolve_model(0.4 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.4 |nbody_system.time, 6)
instance.parameters.end_time_accuracy_factor = -0.5
instance.evolve_model(0.5 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.48974930698 |nbody_system.time, 6)
instance.parameters.end_time_accuracy_factor = +0.5
instance.evolve_model(0.6 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.6042733579 |nbody_system.time, 6)
instance.stop()
def test19(self):
particles = datamodel.Particles(2)
particles.x = [0.0,200.0] | nbody_system.length
particles.y = 0.0 | nbody_system.length
particles.z = 0.0 | nbody_system.length
particles.vx = 0.0 | nbody_system.speed
particles.vy = 0.0 | nbody_system.speed
particles.vz = 0.0 | nbody_system.speed
particles.mass = 1.0 | nbody_system.mass
instance = Hermite()
instance.particles.add_particles(particles)
instance.commit_particles()
self.assertEquals(instance.particles[0].radius, 0.0 | nbody_system.length)
instance.parameters.end_time_accuracy_factor = 0.0
instance.evolve_model(0.1 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.1 |nbody_system.time, 5)
instance.stop()
def test19(self):
particles = datamodel.Particles(2)
particles.x = [0.0,200.0] | nbody_system.length
particles.y = 0.0 | nbody_system.length
particles.z = 0.0 | nbody_system.length
particles.vx = 0.0 | nbody_system.speed
particles.vy = 0.0 | nbody_system.speed
particles.vz = 0.0 | nbody_system.speed
particles.mass = 1.0 | nbody_system.mass
instance = Hermite()
instance.particles.add_particles(particles)
instance.commit_particles()
self.assertEquals(instance.particles[0].radius, 0.0 | nbody_system.length)
instance.parameters.end_time_accuracy_factor = 0.0
instance.evolve_model(0.1 | nbody_system.time)
self.assertAlmostRelativeEquals(instance.model_time, 0.1 |nbody_system.time, 5)
instance.stop()
def test7(self):
print "Test7: Testing effect of Hermite 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 = Hermite(convert_nbody)
instance.parameters.end_time_accuracy_factor = 0.0
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 test7(self):
print "Test7: Testing effect of Hermite 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 = Hermite(convert_nbody)
instance.parameters.end_time_accuracy_factor = 0.0
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))
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
instance = Hermite(convert_nbody)
instance.initialize_code()
instance.particles.add_particles(particles)
instance.commit_particles()
channelp = instance.particles.new_channel_to(particles)
start = 0 |units.yr
end = 150 | units.yr
step = 10|units.day
timerange = VectorQuantity.arange(start, end, step)
masses = []|units.MSun
for i, time in enumerate(timerange):
instance.evolve_model(time)
channelp.copy()
particles.savepoint(time)
def new_star_code_hermite(self):
result = Hermite(self.converter)
result.parameters.epsilon_squared = self.star_epsilon ** 2
result.particles.add_particles(self.new_particles_cluster())
result.commit_particles()
return result
def new_star_code_hermite(self):
result = Hermite()
result.parameters.epsilon_squared = self.star_epsilon**2
result.particles.add_particles(self.new_particles_cluster())
result.commit_particles()
return result
