MFEM  v4.6.0
Finite element discretization library
Public Member Functions | List of all members
mfem::RAPOperator Class Reference

The operator x -> R*A*P*x constructed through the actions of R^T, A and P. More...

#include <operator.hpp>

Inheritance diagram for mfem::RAPOperator:
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Collaboration diagram for mfem::RAPOperator:
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Public Member Functions

 RAPOperator (const Operator &Rt_, const Operator &A_, const Operator &P_)
 Construct the RAP operator given R^T, A and P. More...
 
virtual MemoryClass GetMemoryClass () const
 Return the MemoryClass preferred by the Operator. More...
 
virtual void Mult (const Vector &x, Vector &y) const
 Operator application. More...
 
virtual void AssembleDiagonal (Vector &diag) const
 Approximate diagonal of the RAP Operator. More...
 
virtual void MultTranspose (const Vector &x, Vector &y) const
 Application of the transpose. More...
 
- Public Member Functions inherited from mfem::Operator
void InitTVectors (const Operator *Po, const Operator *Ri, const Operator *Pi, Vector &x, Vector &b, Vector &X, Vector &B) const
 Initializes memory for true vectors of linear system. More...
 
 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 AddMult (const Vector &x, Vector &y, const double a=1.0) const
 Operator application: y+=A(x) (default) or y+=a*A(x). More...
 
virtual void AddMultTranspose (const Vector &x, Vector &y, const double a=1.0) const
 Operator transpose application: y+=A^t(x) (default) or y+=a*A^t(x). More...
 
virtual void ArrayMult (const Array< const Vector *> &X, Array< Vector *> &Y) const
 Operator application on a matrix: Y=A(X). More...
 
virtual void ArrayMultTranspose (const Array< const Vector *> &X, Array< Vector *> &Y) const
 Action of the transpose operator on a matrix: Y=A^t(X). More...
 
virtual void ArrayAddMult (const Array< const Vector *> &X, Array< Vector *> &Y, const double a=1.0) const
 Operator application on a matrix: Y+=A(X) (default) or Y+=a*A(X). More...
 
virtual void ArrayAddMultTranspose (const Array< const Vector *> &X, Array< Vector *> &Y, const double a=1.0) const
 Operator transpose application on a matrix: Y+=A^t(X) (default) or Y+=a*A^t(X). More...
 
virtual OperatorGetGradient (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 OperatorGetProlongation () const
 Prolongation operator from linear algebra (linear system) vectors, to input vectors for the operator. NULL means identity. More...
 
virtual const OperatorGetRestriction () const
 Restriction operator from input vectors for the operator to linear algebra (linear system) vectors. NULL means identity. More...
 
virtual const OperatorGetOutputProlongation () const
 Prolongation operator from linear algebra (linear system) vectors, to output vectors for the operator. NULL means identity. More...
 
virtual const OperatorGetOutputRestrictionTranspose () const
 Transpose of GetOutputRestriction, directly available in this form to facilitate matrix-free RAP-type operators. More...
 
virtual const OperatorGetOutputRestriction () const
 Restriction operator from output 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...
 
void FormRectangularLinearSystem (const Array< int > &trial_tdof_list, const Array< int > &test_tdof_list, Vector &x, Vector &b, Operator *&A, Vector &X, Vector &B)
 Form a column-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() or Operator::FormRectangularLinearSystem(). More...
 
void FormSystemOperator (const Array< int > &ess_tdof_list, Operator *&A)
 Return in A a parallel (on truedofs) version of this square operator. More...
 
void FormRectangularSystemOperator (const Array< int > &trial_tdof_list, const Array< int > &test_tdof_list, Operator *&A)
 Return in A a parallel (on truedofs) version of this rectangular operator (including constraints). More...
 
void FormDiscreteOperator (Operator *&A)
 Return in A a parallel (on truedofs) version of this rectangular operator. More...
 
void PrintMatlab (std::ostream &out, int n, int m=0) const
 Prints operator with input size n and output size m in Matlab format. More...
 
virtual void PrintMatlab (std::ostream &out) const
 Prints operator in Matlab format. More...
 
virtual ~Operator ()
 Virtual destructor. More...
 
Type GetType () const
 Return the type ID of the Operator class. More...
 

Additional Inherited Members

- Public Types inherited from mfem::Operator
enum  DiagonalPolicy { DIAG_ZERO, DIAG_ONE, DIAG_KEEP }
 Defines operator diagonal policy upon elimination of rows and/or columns. More...
 
enum  Type {
  ANY_TYPE, MFEM_SPARSEMAT, Hypre_ParCSR, PETSC_MATAIJ,
  PETSC_MATIS, PETSC_MATSHELL, PETSC_MATNEST, PETSC_MATHYPRE,
  PETSC_MATGENERIC, Complex_Operator, MFEM_ComplexSparseMat, Complex_Hypre_ParCSR,
  Complex_DenseMat, MFEM_Block_Matrix, MFEM_Block_Operator
}
 Enumeration defining IDs for some classes derived from Operator. More...
 
- Protected Member Functions inherited from mfem::Operator
void FormConstrainedSystemOperator (const Array< int > &ess_tdof_list, ConstrainedOperator *&Aout)
 see FormSystemOperator() More...
 
void FormRectangularConstrainedSystemOperator (const Array< int > &trial_tdof_list, const Array< int > &test_tdof_list, RectangularConstrainedOperator *&Aout)
 see FormRectangularSystemOperator() More...
 
OperatorSetupRAP (const Operator *Pi, const Operator *Po)
 Returns RAP Operator of this, using input/output Prolongation matrices Pi corresponds to "P", Po corresponds to "Rt". More...
 
- Protected Attributes inherited from mfem::Operator
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

The operator x -> R*A*P*x constructed through the actions of R^T, A and P.

Definition at line 794 of file operator.hpp.

Constructor & Destructor Documentation

◆ RAPOperator()

mfem::RAPOperator::RAPOperator ( const Operator Rt_,
const Operator A_,
const Operator P_ 
)

Construct the RAP operator given R^T, A and P.

Definition at line 395 of file operator.cpp.

Member Function Documentation

◆ AssembleDiagonal()

virtual void mfem::RAPOperator::AssembleDiagonal ( Vector diag) const
inlinevirtual

Approximate diagonal of the RAP Operator.

Returns the diagonal of A, as returned by its AssembleDiagonal method, multiplied be P^T.

When P is the FE space prolongation operator on a mesh without hanging nodes and Rt = P, the returned diagonal is exact, as long as the diagonal of A is also exact.

Reimplemented from mfem::Operator.

Definition at line 821 of file operator.hpp.

◆ GetMemoryClass()

virtual MemoryClass mfem::RAPOperator::GetMemoryClass ( ) const
inlinevirtual

Return the MemoryClass preferred by the Operator.

This is the MemoryClass that will be used to access the input and output vectors in the Mult() and MultTranspose() methods.

For example, classes using the mfem::forall macro for implementation can return the value returned by Device::GetMemoryClass().

The default implementation of this method in class Operator returns MemoryClass::HOST.

Reimplemented from mfem::Operator.

Definition at line 808 of file operator.hpp.

◆ Mult()

virtual void mfem::RAPOperator::Mult ( const Vector x,
Vector y 
) const
inlinevirtual

Operator application.

Implements mfem::Operator.

Definition at line 811 of file operator.hpp.

◆ MultTranspose()

virtual void mfem::RAPOperator::MultTranspose ( const Vector x,
Vector y 
) const
inlinevirtual

Application of the transpose.

Reimplemented from mfem::Operator.

Definition at line 832 of file operator.hpp.


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