MFEMEigenvaluesPostprocessor

Overview

Retrieves the computed eigenvalues from an MFEM eigensolver after each solve and exports them as a vector quantity. This postprocessor must be used in conjunction with an MFEMEigenproblem problem type; using it with any other problem type will result in an error.

The number of eigenvalues reported corresponds to the num_modes parameter set on MFEMEigenproblem. The eigenvalues are stored in ascending order and are typically written to a CSV output file for further analysis.

Example Input File Syntax

[VectorPostprocessors<<<{"href": "../../../syntax/VectorPostprocessors/index.html"}>>>]
  [eigenvalues]
    type = MFEMEigenvaluesPostprocessor<<<{"description": "Retrieves the eigenvalues from an eigensolve for exporting.", "href": "MFEMEigenvaluesPostprocessor.html"}>>>
  []
[]

[Outputs<<<{"href": "../../../syntax/Outputs/index.html"}>>>]
  [ReportedPostprocessors]
    type = CSV<<<{"description": "Output for postprocessors, vector postprocessors, and scalar variables using comma seperated values (CSV).", "href": "../../outputs/CSV.html"}>>>
    file_base<<<{"description": "The desired solution output name without an extension. If not provided, MOOSE sets it with Outputs/file_base when available. Otherwise, MOOSE uses input file name and this object name for a master input or uses master file_base, the subapp name and this object name for a subapp input to set it."}>>> = OutputData/DiffusionEigenproblem
  []
[]

Input Parameters

contains_complete_historyFalseSet this flag to indicate that the values in all vectors declared by this VPP represent a time history (e.g. with each invocation, new values are added and old values are never removed). This changes the output so that only a single file is output and updated with each invocation
Default:False
C++ Type:bool
Controllable:No
Description:Set this flag to indicate that the values in all vectors declared by this VPP represent a time history (e.g. with each invocation, new values are added and old values are never removed). This changes the output so that only a single file is output and updated with each invocation
execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
Default:TIMESTEP_END
C++ Type:ExecFlagEnum
Options:XFEM_MARK, FORWARD, ADJOINT, HOMOGENEOUS_FORWARD, ADJOINT_TIMESTEP_BEGIN, ADJOINT_TIMESTEP_END, NONE, INITIAL, LINEAR, LINEAR_CONVERGENCE, NONLINEAR, NONLINEAR_CONVERGENCE, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, MULTIAPP_FIXED_POINT_CONVERGENCE, FINAL, CUSTOM
Controllable:No
Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
parallel_typeREPLICATEDSet how the data is represented within the VectorPostprocessor (VPP); 'distributed' indicates that data within the VPP is distributed and no auto communication is performed, this setting will result in parallel output within the CSV output; 'replicated' indicates that the data within the VPP is correct on processor 0, the data will automatically be broadcast to all processors unless the '_auto_broadcast' param is set to false within the validParams function.
Default:REPLICATED
C++ Type:MooseEnum
Options:DISTRIBUTED, REPLICATED
Controllable:No
Description:Set how the data is represented within the VectorPostprocessor (VPP); 'distributed' indicates that data within the VPP is distributed and no auto communication is performed, this setting will result in parallel output within the CSV output; 'replicated' indicates that the data within the VPP is correct on processor 0, the data will automatically be broadcast to all processors unless the '_auto_broadcast' param is set to false within the validParams function.

Optional Parameters

control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Controllable:No
Description:Adds user-defined labels for accessing object parameters via control logic.
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:No
Description:Set the enabled status of the MooseObject.
outputsVector of output names where you would like to restrict the output of variables(s) associated with this object
C++ Type:std::vector<OutputName>
Controllable:No
Description:Vector of output names where you would like to restrict the output of variables(s) associated with this object

Advanced Parameters

Input Files

(test/tests/mfem/kernels/diffusion_eigenproblem.i)
(test/tests/mfem/kernels/maxwell_eigenproblem.i)

(test/tests/mfem/kernels/diffusion_eigenproblem.i)

[Mesh]
  type = MFEMMesh
  file = ../mesh/star.mesh
  dim = 2
  serial_refine = 1
[]

[Problem]
  type = MFEMEigenproblem
  num_modes = 5
[]

[FESpaces]
  [H1FESpace]
    type = MFEMScalarFESpace
    fec_type = H1
    fec_order = FIRST
  []
[]

[Variables]
  [u]
    type = MFEMVariable
    fespace = H1FESpace
  []
[]

[BCs]
  [all]
    type = MFEMScalarDirichletBC
    variable = u
    coefficient = 1.0
  []
[]

[Kernels]
  [diff]
    type = MFEMDiffusionKernel
    variable = u
  []
[]

[Preconditioner]
  [boomeramg]
    type = MFEMHypreBoomerAMG
    print_level = 0
  []
[]

[Solver]
  type = MFEMHypreLOBPCG
  preconditioner = boomeramg
  print_level = 0
  l_tol = 1e-10
  l_max_its = 300
  random_seed = 75
[]

[Executioner]
  type = MFEMSteady
  device = cpu
[]

[VectorPostprocessors]
  [eigenvalues]
    type = MFEMEigenvaluesPostprocessor
  []
[]

[Outputs]
  [ReportedPostprocessors]
    type = CSV
    file_base = OutputData/DiffusionEigenproblem
  []
[]

(test/tests/mfem/kernels/diffusion_eigenproblem.i)

[Mesh]
  type = MFEMMesh
  file = ../mesh/star.mesh
  dim = 2
  serial_refine = 1
[]

[Problem]
  type = MFEMEigenproblem
  num_modes = 5
[]

[FESpaces]
  [H1FESpace]
    type = MFEMScalarFESpace
    fec_type = H1
    fec_order = FIRST
  []
[]

[Variables]
  [u]
    type = MFEMVariable
    fespace = H1FESpace
  []
[]

[BCs]
  [all]
    type = MFEMScalarDirichletBC
    variable = u
    coefficient = 1.0
  []
[]

[Kernels]
  [diff]
    type = MFEMDiffusionKernel
    variable = u
  []
[]

[Preconditioner]
  [boomeramg]
    type = MFEMHypreBoomerAMG
    print_level = 0
  []
[]

[Solver]
  type = MFEMHypreLOBPCG
  preconditioner = boomeramg
  print_level = 0
  l_tol = 1e-10
  l_max_its = 300
  random_seed = 75
[]

[Executioner]
  type = MFEMSteady
  device = cpu
[]

[VectorPostprocessors]
  [eigenvalues]
    type = MFEMEigenvaluesPostprocessor
  []
[]

[Outputs]
  [ReportedPostprocessors]
    type = CSV
    file_base = OutputData/DiffusionEigenproblem
  []
[]

(test/tests/mfem/kernels/maxwell_eigenproblem.i)

[Mesh]
  type = MFEMMesh
  file = ../mesh/beam-tet.mesh
  dim = 3
[]

[Problem]
  type = MFEMEigenproblem
  num_modes = 5
[]

[FESpaces]
  [HCurlFESpace]
    type = MFEMVectorFESpace
    fec_type = ND
    fec_order = FIRST
  []
[]

[Variables]
  [E]
    type = MFEMVariable
    fespace = HCurlFESpace
  []
[]

[BCs]
  [all]
    type = MFEMVectorTangentialDirichletBC
    variable = E
    vector_coefficient = '0 0 0'
  []
[]

[Kernels]
  [diff]
    type = MFEMCurlCurlKernel
    variable = E
  []
[]

[Preconditioner]
  [ams]
    type = MFEMHypreAMS
    fespace = HCurlFESpace
    print_level = 0
    singular = true
  []
[]

[Solver]
  type = MFEMHypreAME
  preconditioner = ams
  print_level = 0
  l_tol = 1e-8
  l_max_its = 100
[]

[Executioner]
  type = MFEMSteady
  device = cpu
[]

[VectorPostprocessors]
  [eigenvalues]
    type = MFEMEigenvaluesPostprocessor
  []
[]

[Outputs]
  execute_on = 'timestep_end'
  csv = true
  file_base = OutputData/MaxwellEigenproblem
[]

Overview
Example Input File Syntax
Input Parameters
Input Files