Abstract operator. More...

#include <operator.hpp>

Inherited by mfem::BlockOperator, mfem::ConformingProlongationOperator, mfem::ConstrainedOperator, mfem::HypreParMatrix, mfem::IdentityOperator, mfem::Matrix, mfem::miniapps::IrrotationalProjector, mfem::NonlinearForm, mfem::PetscParMatrix, mfem::RAPOperator, mfem::Solver, mfem::STRUMPACKRowLocMatrix, mfem::SuperLURowLocMatrix, mfem::TBilinearForm< meshType, solFESpace, IR, IntegratorType, solVecLayout_t, complex_t, real_t >, mfem::TimeDependentOperator, mfem::TransposeOperator, mfem::TripleProductOperator, ReducedSystemOperator, ReducedSystemOperator, ReducedSystemOperator, ReducedSystemOperator, and ReducedSystemOperator.

Public Types
enum	Type { MFEM_SPARSEMAT, Hypre_ParCSR, PETSC_MATAIJ, PETSC_MATIS, PETSC_MATSHELL, PETSC_MATNEST, PETSC_MATHYPRE, PETSC_MATGENERIC }
	Enumeration defining IDs for some classes derived from Operator. More...

Public Member Functions
	Operator (int s=0)
	Construct a square Operator with given size s (default 0). More...

	Operator (int h, int w)
	Construct an Operator with the given height (output size) and width (input size). More...

int	Height () const
	Get the height (size of output) of the Operator. Synonym with NumRows(). More...

int	NumRows () const
	Get the number of rows (size of output) of the Operator. Synonym with Height(). More...

int	Width () const
	Get the width (size of input) of the Operator. Synonym with NumCols(). More...

int	NumCols () const
	Get the number of columns (size of input) of the Operator. Synonym with Width(). More...

virtual void	Mult (const Vector &x, Vector &y) const =0
	Operator application: `y=A(x)`. More...

virtual void	MultTranspose (const Vector &x, Vector &y) const
	Action of the transpose operator: `y=A^t(x)`. The default behavior in class Operator is to generate an error. More...

virtual Operator &	GetGradient (const Vector &x) const
	Evaluate the gradient operator at the point x. The default behavior in class Operator is to generate an error. More...

virtual const Operator *	GetProlongation () const
	Prolongation operator from linear algebra (linear system) vectors, to input vectors for the operator. `NULL` means identity. More...

virtual const Operator *	GetRestriction () const
	Restriction operator from input vectors for the operator to linear algebra (linear system) vectors. `NULL` means identity. More...

void	FormLinearSystem (const Array< int > &ess_tdof_list, Vector &x, Vector &b, Operator *&A, Vector &X, Vector &B, int copy_interior=0)
	Form a constrained linear system using a matrix-free approach. More...

virtual void	RecoverFEMSolution (const Vector &X, const Vector &b, Vector &x)
	Reconstruct a solution vector x (e.g. a GridFunction) from the solution X of a constrained linear system obtained from Operator::FormLinearSystem(). More...

void	PrintMatlab (std::ostream &out, int n=0, int m=0) const
	Prints operator with input size n and output size m in Matlab format. More...

virtual	~Operator ()
	Virtual destructor. More...

Protected Attributes
int	height
	Dimension of the output / number of rows in the matrix. More...

int	width
	Dimension of the input / number of columns in the matrix. More...

Detailed Description

Abstract operator.

Definition at line 21 of file operator.hpp.

Member Enumeration Documentation

enum mfem::Operator::Type

Enumeration defining IDs for some classes derived from Operator.

Enumerator
MFEM_SPARSEMAT
Hypre_ParCSR
PETSC_MATAIJ
PETSC_MATIS
PETSC_MATSHELL
PETSC_MATNEST
PETSC_MATHYPRE
PETSC_MATGENERIC

Definition at line 123 of file operator.hpp.

Constructor & Destructor Documentation

mfem::Operator::Operator ( int s = 0 )

inlineexplicit

Construct a square Operator with given size s (default 0).

Definition at line 29 of file operator.hpp.

mfem::Operator::Operator	(	int	h,
		int	w
	)

inline

Construct an Operator with the given height (output size) and width (input size).

Definition at line 33 of file operator.hpp.

virtual mfem::Operator::~Operator ( )

inlinevirtual

Virtual destructor.

Definition at line 120 of file operator.hpp.

Member Function Documentation

void mfem::Operator::FormLinearSystem	(	const Array< int > &	ess_tdof_list,
		Vector &	x,
		Vector &	b,
		Operator *&	A,
		Vector &	X,
		Vector &	B,
		int	copy_interior = `0`
	)

Form a constrained linear system using a matrix-free approach.

Assuming square operator, form the operator linear system A(X)=B, corresponding to it and the right-hand side b, by applying any necessary transformations such as: parallel assembly, conforming constraints for non-conforming AMR and eliminating boundary conditions.

Note: Static condensation and hybridization are not supported for general operators (cf. the analogous methods BilinearForm::FormLinearSystem() and ParBilinearForm::FormLinearSystem()).

The constraints are specified through the prolongation P from GetProlongation(), and restriction R from GetRestriction() methods, which are e.g. available through the (parallel) finite element space of any (parallel) bilinear form operator. We assume that the operator is square, using the same input and output space, so we have: A(X)=[P^t (*this) P](X), B=P^t(b), and x=P(X).

The vector x must contain the essential boundary condition values. These are eliminated through the ConstrainedOperator class and the vector X is initialized by setting its essential entries to the boundary conditions and all other entries to zero (copy_interior == 0) or copied from x (copy_interior != 0).

After solving the system A(X)=B, the (finite element) solution x can be recovered by calling Operator::RecoverFEMSolution() with the same vectors X, b, and x.

Note: The caller is responsible for destroying the output operator A!; If there are no transformations, X simply reuses the data of x.

Definition at line 21 of file operator.cpp.

virtual Operator& mfem::Operator::GetGradient ( const Vector & x ) const

inlinevirtual

Evaluate the gradient operator at the point x. The default behavior in class Operator is to generate an error.

Reimplemented in mfem::NonlinearForm, and mfem::ParNonlinearForm.

Definition at line 57 of file operator.hpp.

virtual const Operator* mfem::Operator::GetProlongation ( ) const

inlinevirtual

Prolongation operator from linear algebra (linear system) vectors, to input vectors for the operator. NULL means identity.

Reimplemented in mfem::BilinearForm, mfem::ParBilinearForm, mfem::TBilinearForm< meshType, solFESpace, IR, IntegratorType, solVecLayout_t, complex_t, real_t >, and mfem::ParNonlinearForm.

Definition at line 65 of file operator.hpp.

virtual const Operator* mfem::Operator::GetRestriction ( ) const

inlinevirtual

Restriction operator from input vectors for the operator to linear algebra (linear system) vectors. NULL means identity.

Reimplemented in mfem::BilinearForm, mfem::ParBilinearForm, mfem::TBilinearForm< meshType, solFESpace, IR, IntegratorType, solVecLayout_t, complex_t, real_t >, and mfem::ParNonlinearForm.

Definition at line 68 of file operator.hpp.

int mfem::Operator::Height ( ) const

inline

Get the height (size of output) of the Operator. Synonym with NumRows().

Definition at line 36 of file operator.hpp.

virtual void mfem::Operator::Mult	(	const Vector &	x,
		Vector &	y
	)		const

pure virtual

Operator application: y=A(x).

Implemented in mfem::HypreSolver, mfem::PetscNonlinearSolver, mfem::HypreSmoother, mfem::DenseMatrixInverse, mfem::PetscPreconditioner, mfem::PetscLinearSolver, mfem::ConstrainedOperator, mfem::KLUSolver, mfem::HypreParMatrix, mfem::KinSolver, mfem::MixedBilinearForm, mfem::UMFPackSolver, mfem::TripleProductOperator, mfem::RAPOperator, mfem::SLBQPOptimizer, mfem::TransposeOperator, mfem::ConformingProlongationOperator, mfem::IdentityOperator, mfem::NewtonSolver, mfem::BlockLowerTriangularPreconditioner, mfem::MINRESSolver, mfem::PetscParMatrix, mfem::BiCGSTABSolver, mfem::TimeDependentOperator, mfem::electromagnetics::MagneticDiffusionEOperator, mfem::SparseMatrix, mfem::miniapps::DivergenceFreeProjector, mfem::FGMRESSolver, mfem::BlockDiagonalPreconditioner, mfem::GMRESSolver, mfem::BilinearForm, mfem::miniapps::IrrotationalProjector, mfem::CGSolver, mfem::DenseMatrix, mfem::TBilinearForm< meshType, solFESpace, IR, IntegratorType, solVecLayout_t, complex_t, real_t >, mfem::BlockMatrix, mfem::SuperLUSolver, mfem::SLISolver, mfem::AbstractSparseMatrix, mfem::BlockOperator, FE_Evolution, mfem::STRUMPACKSolver, mfem::NonlinearForm, FE_Evolution, FE_Evolution, mfem::DSmoother, FE_Evolution, FE_Evolution, mfem::SuperLURowLocMatrix, mfem::GSSmoother, mfem::ParNonlinearForm, mfem::STRUMPACKRowLocMatrix, and FE_Evolution.

virtual void mfem::Operator::MultTranspose	(	const Vector &	x,
		Vector &	y
	)		const

inlinevirtual

Action of the transpose operator: y=A^t(x). The default behavior in class Operator is to generate an error.

Reimplemented in mfem::KLUSolver, mfem::HypreParMatrix, mfem::MixedBilinearForm, mfem::UMFPackSolver, mfem::TripleProductOperator, mfem::RAPOperator, mfem::TransposeOperator, mfem::ConformingProlongationOperator, mfem::BlockLowerTriangularPreconditioner, mfem::PetscParMatrix, mfem::SparseMatrix, mfem::BilinearForm, mfem::BlockDiagonalPreconditioner, mfem::DenseMatrix, mfem::BlockMatrix, mfem::AbstractSparseMatrix, and mfem::BlockOperator.

Definition at line 52 of file operator.hpp.

int mfem::Operator::NumCols ( ) const

inline

Get the number of columns (size of input) of the Operator. Synonym with Width().

Definition at line 45 of file operator.hpp.

int mfem::Operator::NumRows ( ) const

inline

Get the number of rows (size of output) of the Operator. Synonym with Height().

Definition at line 39 of file operator.hpp.

void mfem::Operator::PrintMatlab	(	std::ostream &	out,
		int	n = `0`,
		int	m = `0`
	)		const

Prints operator with input size n and output size m in Matlab format.

Definition at line 72 of file operator.cpp.

void mfem::Operator::RecoverFEMSolution	(	const Vector &	X,
		const Vector &	b,
		Vector &	x
	)

virtual

Reconstruct a solution vector x (e.g. a GridFunction) from the solution X of a constrained linear system obtained from Operator::FormLinearSystem().

Call this method after solving a linear system constructed using Operator::FormLinearSystem() to recover the solution as an input vector, x, for this Operator (presumably a finite element grid function). This method has identical signature to the analogous method for bilinear forms, though currently b is not used in the implementation.

Reimplemented in mfem::BilinearForm, and mfem::ParBilinearForm.

Definition at line 57 of file operator.cpp.

int mfem::Operator::Width ( ) const

inline

Get the width (size of input) of the Operator. Synonym with NumCols().

Definition at line 42 of file operator.hpp.

Member Data Documentation

int mfem::Operator::height

protected

Dimension of the output / number of rows in the matrix.

Definition at line 24 of file operator.hpp.

int mfem::Operator::width

protected

Dimension of the input / number of columns in the matrix.

Definition at line 25 of file operator.hpp.

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

Public Types

Public Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation