def _create_linear_solver(self):
"""Create the eigensolver.
This overrides the base class method and replaces the usual linear solver
with an eigenvalue problem solver.
"""
if self.eigensolver_settings["solver_type"].GetString() == "FEAST":
feast_system_solver_settings = self.eigensolver_settings[
"linear_solver_settings"]
if feast_system_solver_settings["solver_type"].GetString(
) == "complex_skyline_lu_solver":
# default built-in feast system solver
linear_solver = ExternalSolversApplication.FEASTSolver(
self.eigensolver_settings)
elif feast_system_solver_settings["solver_type"].GetString(
) == "pastix":
feast_system_solver = ExternalSolversApplication.PastixComplexSolver(
feast_system_solver_settings)
linear_solver = ExternalSolversApplication.FEASTSolver(
self.eigensolver_settings, feast_system_solver)
else:
raise Exception(
"Unsupported FEAST system solver_type: " +
feast_system_solver_settings["solver_type"].GetString())
else:
raise Exception(
"Unsupported eigensolver solver_type: " +
self.eigensolver_settings["solver_type"].GetString())
return linear_solver
def Initialize(self):
self.compute_model_part = self.GetComputeModelPart()
self.eigensolver_settings = self.settings["eigensolver_settings"]
if self.eigensolver_settings["solver_type"].GetString() == "FEAST":
linear_solver_settings = self.eigensolver_settings["linear_solver_settings"]
if linear_solver_settings["solver_type"].GetString() == "skyline_lu":
# default built-in feast system solver
self.eigen_solver = ExternalSolversApplication.FEASTSolver(self.eigensolver_settings)
else:
# external feast system solver
feast_system_solver = self._GetFEASTSystemSolver(linear_solver_settings)
self.eigen_solver = ExternalSolversApplication.FEASTSolver(self.eigensolver_settings, feast_system_solver)
else:
raise Exception("solver_type is not yet implemented: " + self.eigensolver_settings["solver_type"].GetString())
if self.settings["solution_type"].GetString() == "Dynamic":
self.scheme = StructuralMechanicsApplication.EigensolverDynamicScheme()
else:
raise Exception("solution_type is not yet implemented.")
self.builder_and_solver = KratosMultiphysics.ResidualBasedBlockBuilderAndSolver(self.eigen_solver)
self.solver = StructuralMechanicsApplication.EigensolverStrategy(
self.compute_model_part,
self.scheme,
self.builder_and_solver)
def _solve_eigen(self, mp, echo=0):
feast_system_solver_settings = KratosMultiphysics.Parameters("""{ }""")
eigensolver_settings = KratosMultiphysics.Parameters("""
{
"perform_stochastic_estimate": false,
"lambda_min": 1.0e-2,
"lambda_max": 25.0,
"search_dimension": 7
}
""")
if not (hasattr(KratosMultiphysics.ExternalSolversApplication,
"PastixComplexSolver")):
self.skipTest('"PastixComplexSolver" not available')
feast_system_solver = ExternalSolversApplication.PastixComplexSolver(
feast_system_solver_settings)
eigen_solver = ExternalSolversApplication.FEASTSolver(
eigensolver_settings, feast_system_solver)
builder_and_solver = KratosMultiphysics.ResidualBasedBlockBuilderAndSolver(
eigen_solver)
eigen_scheme = StructuralMechanicsApplication.EigensolverDynamicScheme(
)
eig_strategy = StructuralMechanicsApplication.EigensolverStrategy(
mp, eigen_scheme, builder_and_solver)
eig_strategy.SetEchoLevel(echo)
eig_strategy.Solve()
def test_undamped_mdof_system_eigen(self):
import KratosMultiphysics.ExternalSolversApplication as ExternalSolversApplication
# FEAST is available otherwise this test is not being called
if not hasattr(KratosMultiphysics.ExternalSolversApplication,
"PastixSolver"):
self.skipTest("Pastix Solver is not available")
current_model = KratosMultiphysics.Model()
mp = self._set_up_mdof_system(current_model)
#set parameters
mp.Elements[1].SetValue(KratosMultiphysics.NODAL_MASS, 20.0)
mp.Elements[2].SetValue(
StructuralMechanicsApplication.NODAL_DISPLACEMENT_STIFFNESS,
[200.0, 200.0, 200.0])
mp.Elements[3].SetValue(KratosMultiphysics.NODAL_MASS, 40.0)
mp.Elements[4].SetValue(
StructuralMechanicsApplication.NODAL_DISPLACEMENT_STIFFNESS,
[400.0, 400.0, 400.0])
#create solver
eigen_solver_parameters = KratosMultiphysics.Parameters("""
{
"solver_type": "FEAST",
"print_feast_output": false,
"perform_stochastic_estimate": false,
"solve_eigenvalue_problem": true,
"lambda_min": 0.0,
"lambda_max": 4.0e5,
"number_of_eigenvalues": 2,
"search_dimension": 18,
"linear_solver_settings": {
"solver_type" : "pastix",
"echo_level" : 0
}
}""")
feast_system_solver = ExternalSolversApplication.PastixComplexSolver(
eigen_solver_parameters["linear_solver_settings"])
eigen_solver = ExternalSolversApplication.FEASTSolver(
eigen_solver_parameters, feast_system_solver)
scheme = StructuralMechanicsApplication.EigensolverDynamicScheme()
builder_and_solver = KratosMultiphysics.ResidualBasedBlockBuilderAndSolver(
eigen_solver)
solver = StructuralMechanicsApplication.EigensolverStrategy(
mp, scheme, builder_and_solver)
solver.Solve()
current_eigenvalues = [
ev for ev in mp.ProcessInfo[
StructuralMechanicsApplication.EIGENVALUE_VECTOR]
]
analytical_eigenvalues = [5, 20]
for ev in range(len(analytical_eigenvalues)):
self.assertAlmostEqual(current_eigenvalues[ev],
analytical_eigenvalues[ev])
def ConstructSolver(settings):
if not isinstance(settings, KM.Parameters):
raise Exception(
"Input is expected to be provided as a Kratos Parameters object")
solver_type = settings["solver_type"].GetString()
if solver_type == "eigen_eigensystem":
if kratos_utils.CheckIfApplicationsAvailable(
"EigenSolversApplication"):
import KratosMultiphysics.EigenSolversApplication as EiSA
eigen_solver = EiSA.EigensystemSolver(settings)
return eigen_solver
else:
raise Exception("EigenSolversApplication not available")
linear_solver_configuration = settings["linear_solver_settings"]
if linear_solver_configuration.Has(
"solver_type"): # user specified a linear solver
linear_solver = linear_solver_factory.ConstructSolver(
linear_solver_configuration)
else:
linear_solver = linear_solver_factory.CreateFastestAvailableDirectLinearSolver(
)
if solver_type == "power_iteration_eigenvalue_solver":
eigen_solver = KM.PowerIterationEigenvalueSolver(
settings, linear_solver)
elif solver_type == "power_iteration_highest_eigenvalue_solver":
eigen_solver = KM.PowerIterationHighestEigenvalueSolver(
settings, linear_solver)
elif solver_type == "rayleigh_quotient_iteration_eigenvalue_solver":
eigen_solver = KM.RayleighQuotientIterationEigenvalueSolver(
settings, linear_solver)
elif solver_type == "FEAST" or solver_type == "feast":
if kratos_utils.CheckIfApplicationsAvailable(
"ExternalSolversApplication"):
import KratosMultiphysics.ExternalSolversApplication as ExSA
eigen_solver = ExSA.FEASTSolver(settings, linear_solver)
else:
raise Exception("ExternalSolversApplication not available")
else:
raise Exception("Solver type not found. Asking for :" + solver_type)
return eigen_solver
def Initialize(self):
self.eigensolver_settings = self.settings["eigensolver_settings"]
solver_type = self.eigensolver_settings["solver_type"].GetString()
solution_type = self.settings["solution_type"].GetString()
if solver_type == "FEAST":
self.linear_solver = KratosExternal.FEASTSolver(self.eigensolver_settings)
else:
raise Exception("solver_type is not yet implemented.")
if solution_type == "Dynamic":
self.scheme = KratosStructural.EigensolverDynamicScheme()
else:
raise Exception("solution_type is not yet implemented.")
self.builder_and_solver = KratosMultiphysics.ResidualBasedBlockBuilderAndSolver(self.linear_solver)
self.solver = KratosStructural.EigensolverStrategy(
self.main_model_part,
self.scheme,
self.builder_and_solver)
