def test_gravity(self):
g_const = [1, 2, 3]
gravity = constraints.Gravity(g=g_const)
self.assertSequenceEqual(gravity.g, g_const)
self.system.constraints.add(gravity)
if espressomd.has_features("MASS"):
p = self.system.part.add(pos=[0, 0, 0], mass=3.1)
else:
p = self.system.part.add(pos=[0, 0, 0])
self.system.integrator.run(0)
np.testing.assert_almost_equal(g_const, np.copy(p.f) / p.mass)
self.assertAlmostEqual(self.system.analysis.energy()['total'], 0.)
def test_gravity(self):
g_const = np.array([1, 2, 3])
gravity = constraints.Gravity(g=g_const)
np.testing.assert_almost_equal(g_const, np.copy(gravity.g))
self.system.constraints.add(gravity)
if espressomd.has_features("MASS"):
p = self.system.part.add(pos=[0, 0, 0], mass=3.1)
else:
p = self.system.part.add(pos=[0, 0, 0])
self.system.integrator.run(0)
np.testing.assert_almost_equal(g_const, np.copy(p.f) / p.mass)
self.assertAlmostEqual(self.system.analysis.energy()['total'], 0.)
# Virtual sites don't feel gravity
if espressomd.has_features("VIRTUAL_SITES"):
self.system.part[0].virtual = True
self.system.integrator.run(0)
np.testing.assert_allclose(np.copy(self.system.part[0].f), 0)
acc_time_series.update()
acc_correlator.update()
system.part[0].pos = [1.0, 2.0, 3.0]
acc_mean_variance.update()
acc_time_series.update()
acc_correlator.update()
system.auto_update_accumulators.add(acc_mean_variance)
system.auto_update_accumulators.add(acc_time_series)
system.auto_update_accumulators.add(acc_correlator)
# constraints
system.constraints.add(shape=Sphere(center=system.box_l / 2, radius=0.1),
particle_type=17)
system.constraints.add(shape=Wall(normal=[1. / np.sqrt(3)] * 3, dist=0.5))
system.constraints.add(constraints.Gravity(g=[1., 2., 3.]))
system.constraints.add(constraints.HomogeneousMagneticField(H=[1., 2., 3.]))
system.constraints.add(
constraints.HomogeneousFlowField(u=[1., 2., 3.], gamma=2.3))
pot_field_data = constraints.ElectricPotential.field_from_fn(
system.box_l, np.ones(3), lambda x: np.linalg.norm(10 * np.ones(3) - x))
checkpoint.register("pot_field_data")
system.constraints.add(
constraints.PotentialField(field=pot_field_data,
grid_spacing=np.ones(3),
default_scale=1.6))
vec_field_data = constraints.ForceField.field_from_fn(
system.box_l, np.ones(3), lambda x: 10 * np.ones(3) - x)
checkpoint.register("vec_field_data")
system.constraints.add(
constraints.ForceField(field=vec_field_data,
