mfem::L2ProjectionGridTransfer Class Reference

Transfer data between a coarse mesh and an embedded refined mesh using L2 projection. More...

#include <fespace.hpp>

Inheritance diagram for mfem::L2ProjectionGridTransfer:

Collaboration diagram for mfem::L2ProjectionGridTransfer:

Classes
class	L2Projection
class	L2Prolongation

Public Member Functions
	L2ProjectionGridTransfer (FiniteElementSpace &coarse_fes, FiniteElementSpace &fine_fes)
virtual const Operator &	ForwardOperator ()
	Return an Operator that transfers GridFunctions from the domain FE space to GridFunctions in the range FE space. More...
virtual const Operator &	BackwardOperator ()
	Return an Operator that transfers GridFunctions from the range FE space back to GridFunctions in the domain FE space. More...
Public Member Functions inherited from mfem::GridTransfer
	GridTransfer (FiniteElementSpace &dom_fes_, FiniteElementSpace &ran_fes_)
virtual	~GridTransfer ()
	Virtual destructor. More...
void	SetOperatorType (Operator::Type type)
	Set the desired Operator::Type for the construction of all operators defined by the underlying transfer algorithm. More...
virtual const Operator &	TrueForwardOperator ()
	Return an Operator that transfers true-dof Vectors from the domain FE space to true-dof Vectors in the range FE space. More...
virtual const Operator &	TrueBackwardOperator ()
	Return an Operator that transfers true-dof Vectors from the range FE space back to true-dof Vectors in the domain FE space. More...

Protected Attributes
L2Projection *	F
	Forward, coarse-to-fine, operator. More...
L2Prolongation *	B
	Backward, fine-to-coarse, operator. More...
Protected Attributes inherited from mfem::GridTransfer
FiniteElementSpace &	dom_fes
	Domain FE space. More...
FiniteElementSpace &	ran_fes
	Range FE space. More...
Operator::Type	oper_type
	Desired Operator::Type for the construction of all operators defined by the underlying transfer algorithm. It can be ignored by derived classes. More...
OperatorHandle	fw_t_oper
	Forward true-dof operator. More...
OperatorHandle	bw_t_oper
	Backward true-dof operator. More...
bool	parallel

Additional Inherited Members
Protected Member Functions inherited from mfem::GridTransfer
bool	Parallel () const
const Operator &	MakeTrueOperator (FiniteElementSpace &fes_in, FiniteElementSpace &fes_out, const Operator &oper, OperatorHandle &t_oper)

Detailed Description

Transfer data between a coarse mesh and an embedded refined mesh using L2 projection.

The forward, coarse-to-fine, transfer uses L2 projection. The backward, fine-to-coarse, transfer is defined locally (on a coarse element) as B = (F^t M_f F)^{-1} F^t M_f, where F is the forward transfer matrix, and M_f is the mass matrix on the union of all fine elements comprising the coarse element. Note that the backward transfer operator, B, is a left inverse of the forward transfer operator, F, i.e. B F = I. Both F and B are defined in physical space and, generally, vary between different mesh elements.

This class currently only fully supports L2 finite element spaces and fine meshes that are a uniform refinement of the coarse mesh. Generally, the coarse and fine FE spaces can have different orders, however, in order for the backward operator to be well-defined, the number of the fine dofs (in a coarse element) should not be smaller than the number of coarse dofs.

If used on H1 finite element spaces, the transfer will be performed locally, and the value of shared (interface) degrees of freedom will be determined by the value of the last transfer to be performed (according to the element numbering in the finite element space). As a consequence, the mass conservation properties for this operator from the L2 case do not carry over to H1 spaces.

Definition at line 859 of file fespace.hpp.

Constructor & Destructor Documentation

mfem::L2ProjectionGridTransfer::L2ProjectionGridTransfer ( FiniteElementSpace &  coarse_fes, FiniteElementSpace &  fine_fes  )

inline

Definition at line 908 of file fespace.hpp.

Member Function Documentation

const Operator & mfem::L2ProjectionGridTransfer::BackwardOperator ( )

virtual

Return an Operator that transfers GridFunctions from the range FE space back to GridFunctions in the domain FE space.

Implements mfem::GridTransfer.

Definition at line 2745 of file fespace.cpp.

const Operator & mfem::L2ProjectionGridTransfer::ForwardOperator ( )

virtual

Return an Operator that transfers GridFunctions from the domain FE space to GridFunctions in the range FE space.

Implements mfem::GridTransfer.

Definition at line 2739 of file fespace.cpp.

Member Data Documentation

L2Prolongation* mfem::L2ProjectionGridTransfer::B

protected

Backward, fine-to-coarse, operator.

Definition at line 905 of file fespace.hpp.

L2Projection* mfem::L2ProjectionGridTransfer::F

protected

Forward, coarse-to-fine, operator.

Definition at line 904 of file fespace.hpp.

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

• fem/fespace.hpp
• fem/fespace.cpp