def __init__(self, params, physics, mesh):
super().__init__(params, physics, mesh)
self.stepper = stepper_tools.set_stepper(params, self.state_coeffs)
stepper_tools.set_time_stepping_approach(self.stepper, params)
stepper_tools.set_source_treatment(physics)
# Precompute helpers
self.precompute_matrix_helpers()
if self.limiters:
for limiter in self.limiters:
limiter.precompute_helpers(self)
physics.conv_flux_fcn.alloc_helpers(
np.zeros([
mesh.num_interior_faces,
self.int_face_helpers.quad_wts.shape[0], physics.NUM_STATE_VARS
]))
if physics.diff_flux_fcn:
physics.diff_flux_fcn.alloc_helpers(
np.zeros([
mesh.num_interior_faces,
self.int_face_helpers.quad_wts.shape[0],
physics.NUM_STATE_VARS
]))
# Construct the necessary functions dependent upon required physics
solver_tools.set_function_definitions(self, params)
# Initial condition
if params["RestartFile"] is None:
self.init_state_from_fcn()
def set_split_schemes(self, explicit, implicit, U):
'''
Specifies the explicit and implicit schemes to be used in the
operator splitting technique
Inputs:
-------
explicit: name of chosen explicit scheme from params
implicit: name of chosen implicit (ODE) solver from params
U: solution state vector used to initialize solver
[num_elems, nb, ns]
Outputs:
--------
explicit: stepper object instantiation for explicit scheme
implicit: stepper object instantiation for ODE solver
'''
param = {"TimeStepper": explicit}
# call set_stepper from stepper tools for the explicit scheme
self.explicit = stepper_tools.set_stepper(param, U)
if SourceStepperType[implicit] == SourceStepperType.BDF1:
self.implicit = source_stepper.SourceSolvers.BDF1(U)
elif SourceStepperType[implicit] == SourceStepperType.Trapezoidal:
self.implicit = source_stepper.SourceSolvers.Trapezoidal(U)
elif SourceStepperType[implicit] == SourceStepperType.LSODA:
self.implicit = source_stepper.SourceSolvers.LSODA(U)
else:
raise NotImplementedError("Time scheme not supported")
def test_set_stepper_SSPRK3():
'''
Checks setter function for stepper SSPRK3
'''
time_scheme = "SSPRK3"
params = {'TimeStepper': time_scheme}
stepper = stepper_tools.set_stepper(params, None)
expected = stepper_defs.SSPRK3(None)
assert stepper == expected
def test_set_stepper_LSRK4():
'''
Checks setter function for stepper LSRK4
'''
time_scheme = "LSRK4"
params = {'TimeStepper': time_scheme}
stepper = stepper_tools.set_stepper(params, None)
expected = stepper_defs.LSRK4(None)
assert stepper == expected
def test_set_stepper_not_FE():
'''
Checks setter function for stepper not FE
'''
time_scheme = "RK4"
params = {'TimeStepper': time_scheme}
stepper = stepper_tools.set_stepper(params, None)
expected = stepper_defs.FE(None)
assert stepper != expected
def test_set_stepper_Strang():
'''
Checks setter function for stepper Strang
'''
time_scheme = "Strang"
params = {
'TimeStepper': time_scheme,
'OperatorSplittingExplicit': 'SSPRK3',
'OperatorSplittingImplicit': 'BDF1',
}
stepper = stepper_tools.set_stepper(params, None)
expected = stepper_defs.Strang(None)
assert stepper == expected