Moose::MFEM::ProblemOperatorBase Class Reference

Connects MFEMProblem's MOOSE solver objects to EquationSystem's mathematics. More...

#include <ProblemOperatorBase.h>

Inheritance diagram for Moose::MFEM::ProblemOperatorBase:

Public Member Functions
	ProblemOperatorBase (MFEMProblem &problem)
virtual	~ProblemOperatorBase ()=default
virtual void	SetGridFunctions ()
virtual void	SetTrialVariablesFromTrueVectors ()
virtual void	Init (mfem::BlockVector &X)
virtual void	Solve ()=0

Public Attributes
mfem::Array< int >	_block_true_offsets_test
mfem::Array< int >	_block_true_offsets_trial
mfem::BlockVector	_true_x
mfem::BlockVector	_true_rhs

Protected Member Functions
void	SolveWithOperator (mfem::Operator &system_operator, mfem::Operator &linear_operator, const mfem::Vector &rhs, mfem::Vector &x)
	Solve the current system operator using the configured nonlinear and linear solvers.
void	SolveWithOperator (mfem::Operator &system_operator, const mfem::Vector &rhs, mfem::Vector &x)
	Solve the current system operator using system_operator.GetGradient(x) as the linear operator.

Protected Attributes
MFEMProblem &	_problem
	Reference to the current problem.
MFEMProblemData &	_problem_data
std::vector< std::string >	_trial_var_names
	Vector of names of state gridfunctions used in formulation, ordered by appearance in block vector during solve.
std::vector< std::string >	_test_var_names
std::vector< mfem::ParGridFunction * >	_trial_variables
std::vector< mfem::ParGridFunction * >	_test_variables
mfem::Vector *	_trial_true_vector = nullptr

Detailed Description

Connects MFEMProblem's MOOSE solver objects to EquationSystem's mathematics.

Three distinct layers collaborate to run an MFEM solve inside MOOSE:

• MFEMProblem owns MOOSE infrastructure: the object factory, the action system, ProblemData, and the configured solver objects. Embedding the mfem::Operator solve-dispatch logic here would couple MOOSE's object-management layer directly to specific MFEM operator patterns, so it delegates to ProblemOperator instead.
• EquationSystem owns the mathematics: it builds weak-form components (bilinear/linear/nonlinear forms contributed by kernels and BCs), forms the constrained linear part, retains nonlinear action forms for residual/Jacobian evaluation, and exposes the resulting mfem::Operator interface consumed by both linear solvers (CG, GMRES, direct) and nonlinear solvers (Newton). Solver selection is a user-configuration concern owned by MFEMProblem; coupling it into EquationSystem would conflate the mathematical description of a PDE with how MOOSE happens to solve it.
• ProblemOperator (this class) connects the two. It provides:
  1. The steady vs. time-dependent dispatch boundary: all subclasses implement Solve() as the MOOSE-level entry point ("do whatever this step requires"). Transient subclasses additionally inherit from mfem::TimeDependentOperator and implement ImplicitSolve(dt, t, x) - a different, MFEM-level contract that MFEM's ODE solvers (BackwardEuler, SDIRK, etc.) call internally. Solve() and ImplicitSolve() live at different abstraction layers and are not interchangeable; ImplicitSolve() carries dt and t precisely because it is the per-step callback in an ODE integration loop.
  2. SolveWithOperator() - the linear/nonlinear dispatch that requires knowing which MOOSE solver objects are configured (jacobian_solver, nonlinear_solver).
  3. Block-vector bookkeeping (trial/test true-DoF offsets and vectors) that bridges between the true-DoF algebraic world with the FE gridfunction world.

Definition at line 52 of file ProblemOperatorBase.h.

Constructor & Destructor Documentation

ProblemOperatorBase()

Moose::MFEM::ProblemOperatorBase::ProblemOperatorBase

(

MFEMProblem &

problem

)

Definition at line 19 of file ProblemOperatorBase.C.

  : _problem(problem), _problem_data(problem.getProblemData())
{
}

~ProblemOperatorBase()

virtual Moose::MFEM::ProblemOperatorBase::~ProblemOperatorBase ( )

virtualdefault

Member Function Documentation

Init()

void Moose::MFEM::ProblemOperatorBase::Init ( mfem::BlockVector &  X )

virtual

Reimplemented in Moose::MFEM::TimeDependentEquationSystemProblemOperator.

Definition at line 49 of file ProblemOperatorBase.C.

{
  X.Update(_block_true_offsets_trial);
  for (const auto i : index_range(_trial_variables))
    X.GetBlock(i) = _trial_variables[i]->GetTrueVector();
  // Sync the flags from the global vector with the sub-vectors (copies to global vector location)
  X.SyncFromBlocks();
 
  // After initial assignment of X from the grid function, which may contain initial conditions,
  // we alias the grid function to X
  for (const auto i : index_range(_trial_variables))
    _trial_variables[i]->MakeTRef(
        _trial_variables[i]->ParFESpace(), X, _block_true_offsets_trial[i]);
  _trial_true_vector = &X;
}

Referenced by Moose::MFEM::TimeDependentEquationSystemProblemOperator::Init().

SetGridFunctions()

void Moose::MFEM::ProblemOperatorBase::SetGridFunctions ( )

virtual

Reimplemented in Moose::MFEM::ComplexEquationSystemProblemOperator, Moose::MFEM::EquationSystemProblemOperator, Moose::MFEM::ProblemOperator, Moose::MFEM::TimeDependentEquationSystemProblemOperator, and Moose::MFEM::TimeDependentProblemOperator.

Definition at line 25 of file ProblemOperatorBase.C.

{
  _trial_variables = _problem_data.gridfunctions.Get(_trial_var_names);
  _test_variables = _problem_data.gridfunctions.Get(_test_var_names);
 
  // Set operator size and block structure for trial spaces
  _block_true_offsets_trial.SetSize(_trial_variables.size() + 1);
  _block_true_offsets_trial[0] = 0;
  for (const auto ind : index_range(_trial_variables))
    _block_true_offsets_trial[ind + 1] = _trial_variables.at(ind)->ParFESpace()->TrueVSize();
  _block_true_offsets_trial.PartialSum();
 
  // Set operator size and block structure for test spaces
  _block_true_offsets_test.SetSize(_test_variables.size() + 1);
  _block_true_offsets_test[0] = 0;
  for (const auto ind : index_range(_test_variables))
    _block_true_offsets_test[ind + 1] = _test_variables.at(ind)->ParFESpace()->TrueVSize();
  _block_true_offsets_test.PartialSum();
 
  _true_x.Update(_block_true_offsets_trial);
  _true_rhs.Update(_block_true_offsets_test);
}

Referenced by Moose::MFEM::ProblemOperator::SetGridFunctions(), and Moose::MFEM::TimeDependentProblemOperator::SetGridFunctions().

SetTrialVariablesFromTrueVectors()

void Moose::MFEM::ProblemOperatorBase::SetTrialVariablesFromTrueVectors ( )

virtual

Definition at line 66 of file ProblemOperatorBase.C.

{
  mooseAssert(_trial_true_vector, "The true vector should already have been set");
  for (const auto trial_var : _trial_variables)
  {
    // Sync the memory flags from the global true vector to the gridfunction aliases
    trial_var->GetTrueVector().SyncMemory(*_trial_true_vector);
    trial_var->SetFromTrueVector();
  }
}

Referenced by Moose::MFEM::TimeDependentEquationSystemProblemOperator::Solve().

Solve()

virtual void Moose::MFEM::ProblemOperatorBase::Solve ( )

pure virtual

Implemented in Moose::MFEM::ComplexEquationSystemProblemOperator, Moose::MFEM::EigenproblemESProblemOperator, Moose::MFEM::EquationSystemProblemOperator, Moose::MFEM::ProblemOperator, Moose::MFEM::TimeDependentEquationSystemProblemOperator, and Moose::MFEM::TimeDependentProblemOperator.

SolveWithOperator() [1/2]

void Moose::MFEM::ProblemOperatorBase::SolveWithOperator ( mfem::Operator &  system_operator, const mfem::Vector &  rhs, mfem::Vector &  x  )

inlineprotected

Solve the current system operator using system_operator.GetGradient(x) as the linear operator.

Definition at line 77 of file ProblemOperatorBase.h.

  {
    return SolveWithOperator(system_operator, system_operator.GetGradient(x), rhs, x);
  }

SolveWithOperator() [2/2]

void Moose::MFEM::ProblemOperatorBase::SolveWithOperator ( mfem::Operator &  system_operator, mfem::Operator &  linear_operator, const mfem::Vector &  rhs, mfem::Vector &  x  )

protected

Solve the current system operator using the configured nonlinear and linear solvers.

Definition at line 78 of file ProblemOperatorBase.C.

{
  // Nonlinear solver path for both linear and nonlinear problems. (as a linear problem may still
  // intentionally be solved through the nonlinear solver machinery when one is provided)
  if (_problem_data.nonlinear_solver)
  {
    auto & nonlinear_solver = *_problem_data.nonlinear_solver;
    if (nonlinear_solver.RequiresExternalLinearSolver())
    {
      if (!_problem_data.jacobian_solver)
        mooseError("The configured MFEM nonlinear solver requires an external linear solver, but "
                   "none was provided.");
      auto & linear_solver = *_problem_data.jacobian_solver;
      linear_solver.SetOperator(linear_operator);
      nonlinear_solver.SetLinearSolver(linear_solver.GetSolver());
    }
 
    nonlinear_solver.SetOperator(system_operator);
    nonlinear_solver.Mult(rhs, x);
  }
  // Linear solver path for linear problems.
  else
  {
    if (!_problem_data.jacobian_solver)
      mooseError("A linear MFEM solve requires a linear solver, but none was provided.");
 
    auto & linear_solver = *_problem_data.jacobian_solver;
    linear_solver.SetOperator(linear_operator);
    linear_solver.Mult(rhs, x);
  }
}

Referenced by Moose::MFEM::TimeDependentEquationSystemProblemOperator::ImplicitSolve(), Moose::MFEM::ComplexEquationSystemProblemOperator::Solve(), Moose::MFEM::EquationSystemProblemOperator::Solve(), and SolveWithOperator().

Member Data Documentation

_block_true_offsets_test

mfem::Array<int> Moose::MFEM::ProblemOperatorBase::_block_true_offsets_test

Definition at line 63 of file ProblemOperatorBase.h.

Referenced by SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::ProblemOperator::SetGridFunctions(), and Moose::MFEM::TimeDependentProblemOperator::SetGridFunctions().

_block_true_offsets_trial

mfem::Array<int> Moose::MFEM::ProblemOperatorBase::_block_true_offsets_trial

Definition at line 64 of file ProblemOperatorBase.h.

Referenced by Init(), SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::ProblemOperator::SetGridFunctions(), and Moose::MFEM::TimeDependentProblemOperator::SetGridFunctions().

_problem

MFEMProblem& Moose::MFEM::ProblemOperatorBase::_problem

protected

Reference to the current problem.

Definition at line 83 of file ProblemOperatorBase.h.

Referenced by Moose::MFEM::TimeDependentEquationSystemProblemOperator::Init(), and Moose::MFEM::TimeDependentEquationSystemProblemOperator::Solve().

_problem_data

MFEMProblemData& Moose::MFEM::ProblemOperatorBase::_problem_data

protected

Definition at line 84 of file ProblemOperatorBase.h.

Referenced by Moose::MFEM::EigenproblemESProblemOperator::EigenproblemESProblemOperator(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::ImplicitSolve(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::Init(), Moose::MFEM::EigenproblemESProblemOperator::RecoverEigenproblemSolution(), SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::EigenproblemESProblemOperator::Solve(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::Solve(), and SolveWithOperator().

_test_var_names

std::vector<std::string> Moose::MFEM::ProblemOperatorBase::_test_var_names

protected

Definition at line 89 of file ProblemOperatorBase.h.

Referenced by SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::EquationSystemProblemOperator::SetGridFunctions(), and Moose::MFEM::TimeDependentEquationSystemProblemOperator::SetGridFunctions().

_test_variables

std::vector<mfem::ParGridFunction *> Moose::MFEM::ProblemOperatorBase::_test_variables

protected

Definition at line 91 of file ProblemOperatorBase.h.

Referenced by SetGridFunctions(), Moose::MFEM::ProblemOperator::SetGridFunctions(), and Moose::MFEM::TimeDependentProblemOperator::SetGridFunctions().

_trial_true_vector

mfem::Vector* Moose::MFEM::ProblemOperatorBase::_trial_true_vector = nullptr

protected

Definition at line 92 of file ProblemOperatorBase.h.

Referenced by Init(), SetTrialVariablesFromTrueVectors(), and Moose::MFEM::TimeDependentEquationSystemProblemOperator::Solve().

_trial_var_names

std::vector<std::string> Moose::MFEM::ProblemOperatorBase::_trial_var_names

protected

Vector of names of state gridfunctions used in formulation, ordered by appearance in block vector during solve.

Definition at line 88 of file ProblemOperatorBase.h.

Referenced by Moose::MFEM::EigenproblemESProblemOperator::RecoverEigenproblemSolution(), SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::EquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::SetGridFunctions(), and Moose::MFEM::TimeDependentEquationSystemProblemOperator::Solve().

_trial_variables

std::vector<mfem::ParGridFunction *> Moose::MFEM::ProblemOperatorBase::_trial_variables

protected

Definition at line 90 of file ProblemOperatorBase.h.

Referenced by Init(), SetGridFunctions(), Moose::MFEM::ProblemOperator::SetGridFunctions(), Moose::MFEM::TimeDependentProblemOperator::SetGridFunctions(), and SetTrialVariablesFromTrueVectors().

_true_rhs

mfem::BlockVector Moose::MFEM::ProblemOperatorBase::_true_rhs

Definition at line 66 of file ProblemOperatorBase.h.

Referenced by Moose::MFEM::EquationSystemProblemOperator::FormEquationSystemOperator(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::FormEquationSystemOperator(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::ImplicitSolve(), SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::Solve(), and Moose::MFEM::EquationSystemProblemOperator::Solve().

_true_x

mfem::BlockVector Moose::MFEM::ProblemOperatorBase::_true_x

Definition at line 66 of file ProblemOperatorBase.h.

Referenced by Moose::MFEM::EigenproblemESProblemOperator::FormEquationSystemOperator(), Moose::MFEM::EquationSystemProblemOperator::FormEquationSystemOperator(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::FormEquationSystemOperator(), Moose::MFEM::TimeDependentEquationSystemProblemOperator::ImplicitSolve(), SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::SetGridFunctions(), Moose::MFEM::ComplexEquationSystemProblemOperator::Solve(), and Moose::MFEM::EquationSystemProblemOperator::Solve().

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The documentation for this class was generated from the following files:

• include/mfem/problem_operators/ProblemOperatorBase.h
• src/mfem/problem_operators/ProblemOperatorBase.C