def test_modify_mass(self):
name = 'modify_mass'
try:
rebbin = os.path.join(THIS_DIR, 'binaries/' + name + '.sa')
rebxbin = os.path.join(THIS_DIR, 'binaries/' + name + '.rebx')
sa = reboundx.SimulationArchive(rebbin, rebxbin)
except:
sim = rebound.Simulation('binaries/twoplanets.bin')
sim.automateSimulationArchive('binaries/' + name + '.sa',
interval=1e3,
deletefile=True)
rebx = reboundx.Extras(sim)
mod = rebx.load_operator(name)
rebx.add_operator(mod)
ps = sim.particles
ps[0].params['tau_mass'] = -1e4
rebx.save('binaries/' + name + '.rebx')
sim.integrate(1.e4)
sa = reboundx.SimulationArchive('binaries/' + name + '.sa',
'binaries/' + name + '.rebx')
simf, rebx = sa[-1]
sim, rebx = sa[0]
sim.integrate(simf.t)
self.assertEqual(sim.particles[0].x, simf.particles[0].x)
def test_gr(self):
name = 'gr'
try:
rebbin = os.path.join(THIS_DIR, 'binaries/' + name + '.sa')
rebxbin = os.path.join(THIS_DIR, 'binaries/' + name + '.rebx')
sa = reboundx.SimulationArchive(rebbin, rebxbin)
except:
sim = rebound.Simulation('binaries/twoplanets.bin')
sim.automateSimulationArchive('binaries/' + name + '.sa',
interval=1e3,
deletefile=True)
rebx = reboundx.Extras(sim)
force = rebx.load_force(name)
rebx.add_force(force)
force.params['c'] = 1.e4
ps = sim.particles
rebx.save('binaries/' + name + '.rebx')
sim.integrate(1.e4)
sa = reboundx.SimulationArchive('binaries/' + name + '.sa',
'binaries/' + name + '.rebx')
simf, rebx = sa[-1]
sim, rebx = sa[0]
sim.integrate(simf.t)
self.assertEqual(sim.particles[0].x, simf.particles[0].x)
def test_modify_orbits_forces(self):
name = "modify_orbits_forces"
try:
rebbin = os.path.join(THIS_DIR, 'binaries/' + name + '.sa')
rebxbin = os.path.join(THIS_DIR, 'binaries/' + name + '.rebx')
sa = reboundx.SimulationArchive(rebbin, rebxbin)
except:
try:
sim = rebound.Simulation('binaries/twoplanets.bin')
except:
sim = rebound.Simulation()
sim.add(m=1.)
sim.add(m=1.e-4, a=1., e=0.1)
sim.add(m=1.e-4, a=2, e=0.1, inc=0.2)
sim.integrator = "whfast"
sim.dt = sim.particles[1].P / 100
sim.move_to_com()
sim.save('binaries/twoplanets.bin')
sim.automateSimulationArchive('binaries/modify_orbits_forces.sa',
interval=1e3,
deletefile=True)
rebx = reboundx.Extras(sim)
mod = rebx.load_force('binaries/modify_orbits_forces')
rebx.add_force(mod)
ps = sim.particles
ps[1].params['tau_a'] = -1e4
ps[1].params['tau_e'] = -1e3
ps[2].params['tau_e'] = -1e3
ps[2].params['tau_inc'] = -1e3
rebx.save('binaries/modify_orbits_forces.rebx')
sim.integrate(1.e4)
sa = reboundx.SimulationArchive(
'binaries/modify_orbits_forces.sa',
'binaries/modify_orbits_forces.rebx')
simf, rebx = sa[-1]
sim, rebx = sa[0]
sim.integrate(simf.t)
self.assertEqual(sim.particles[0].x, simf.particles[0].x)
def test_pre(self):
for integrator in integrators:
for rebxintegrator in rebxintegrators:
self.setUp()
self.sim.integrator = integrator
self.sim.ri_ias15.epsilon = 0 # use fixed timesteps for ias15 if used, no problem otherwise
self.integforce = self.rebx.load_operator("integrate_force")
self.integforce.params['force'] = self.gr
self.rebx.add_operator(self.integforce,
dtfraction=1.,
timing="pre")
self.sim.integrate(1000)
E = self.rebx.gr_hamiltonian(self.gr)
# Test effect is actually doing something to the pericenter
self.assertGreater(
self.sim.particles[1].pomega,
0.1,
msg='REB integrator: {0}, REBX integrator: {1}'.format(
integrator, rebxintegrator))
# test energy conservtaion
self.assertLess(
np.abs((E - self.E0) / self.E0),
1.e-4,
msg='REB integrator: {0}, REBX integrator: {1}'.format(
integrator, rebxintegrator))
# test bitwise reproducibility starting from an intermediate snapshot
self.sim.simulationarchive_snapshot('test.sa', deletefile=True)
self.rebx.save('test.rebx')
self.sim.integrate(2000)
self.sim.simulationarchive_snapshot('test.sa')
sa = reboundx.SimulationArchive('test.sa', 'test.rebx')
simf, rebxf = sa[-1]
tmax = simf.t
sim, rebx = sa[0]
sim.integrate(tmax)
self.assertEqual(
self.sim.particles[1].x,
sim.particles[1].x,
msg='REB integrator: {0}, REBX integrator: {1}'.format(
integrator, rebxintegrator))
def test_force(self):
for integrator in integrators + ['mercurius']:
for rebxintegrator in rebxintegrators:
self.setUp()
self.sim.integrator = integrator
self.rebx.add_force(self.gr)
self.sim.integrate(1000)
E = self.rebx.gr_hamiltonian(self.gr)
# Test effect is actually doing something to the pericenter
self.assertGreater(
self.sim.particles[1].pomega,
0.1,
msg='REB integrator: {0}, REBX integrator: {1}'.format(
integrator, rebxintegrator))
# test energy conservtaion
self.assertLess(
np.abs((E - self.E0) / self.E0),
1.e-4,
msg='REB integrator: {0}, REBX integrator: {1}'.format(
integrator, rebxintegrator))
# test bitwise reproducibility starting from an intermediate snapshot
self.sim.simulationarchive_snapshot('test.sa', deletefile=True)
self.rebx.save('test.rebx')
self.sim.integrate(2000)
self.sim.simulationarchive_snapshot('test.sa')
sa = reboundx.SimulationArchive('test.sa', 'test.rebx')
simf, rebxf = sa[-1]
tmax = simf.t
sim, rebx = sa[0]
sim.integrate(tmax)
self.assertEqual(
self.sim.particles[1].x,
sim.particles[1].x,
msg='REB integrator: {0}, REBX integrator: {1}'.format(
integrator, rebxintegrator))
