oomph::MatrixVectorProduct Class Reference

#include <matrix_vector_product.h>

Inheritance diagram for oomph::MatrixVectorProduct:

Public Member Functions
	MatrixVectorProduct ()
	Constructor. More...
	MatrixVectorProduct (const MatrixVectorProduct &)=delete
	Broken copy constructor. More...
void	operator= (const MatrixVectorProduct &)=delete
	Broken assignment operator. More...
	~MatrixVectorProduct ()
	Destructor. More...
void	clean_up_memory ()
	clear the memory More...
void	setup (CRDoubleMatrix *matrix_pt, const LinearAlgebraDistribution *col_dist_pt=0)
void	multiply (const DoubleVector &x, DoubleVector &y) const
void	multiply_transpose (const DoubleVector &x, DoubleVector &y) const
const unsigned &	ncol () const
	Access function to the number of columns. More...
Public Member Functions inherited from oomph::DistributableLinearAlgebraObject
	DistributableLinearAlgebraObject ()
	Default constructor - create a distribution. More...
	DistributableLinearAlgebraObject (const DistributableLinearAlgebraObject &matrix)=delete
	Broken copy constructor. More...
void	operator= (const DistributableLinearAlgebraObject &)=delete
	Broken assignment operator. More...
virtual	~DistributableLinearAlgebraObject ()
	Destructor. More...
LinearAlgebraDistribution *	distribution_pt () const
	access to the LinearAlgebraDistribution More...
unsigned	nrow () const
	access function to the number of global rows. More...
unsigned	nrow_local () const
	access function for the num of local rows on this processor. More...
unsigned	nrow_local (const unsigned &p) const
	access function for the num of local rows on this processor. More...
unsigned	first_row () const
	access function for the first row on this processor More...
unsigned	first_row (const unsigned &p) const
	access function for the first row on this processor More...
bool	distributed () const
	distribution is serial or distributed More...
bool	distribution_built () const
void	build_distribution (const LinearAlgebraDistribution *const dist_pt)
void	build_distribution (const LinearAlgebraDistribution &dist)

Private Attributes
bool	Using_trilinos
CRDoubleMatrix *	Oomph_matrix_pt
	an oomph-lib matrix More...
LinearAlgebraDistribution *	Column_distribution_pt
unsigned	Ncol
	number of columns of the matrix More...

Additional Inherited Members
Protected Member Functions inherited from oomph::DistributableLinearAlgebraObject
void	clear_distribution ()

Detailed Description

Matrix vector product helper class - primarily a wrapper to Trilinos's Epetra matrix vector product methods. This allows the epetra matrix to be assembled once and the matrix vector product to be performed many times.

Constructor & Destructor Documentation

MatrixVectorProduct() [1/2]

oomph::MatrixVectorProduct::MatrixVectorProduct ( )

inline

Constructor.

    {
      // null pointers
#ifdef OOMPH_HAS_TRILINOS
      Epetra_matrix_pt = 0;
#endif
      Oomph_matrix_pt = 0;
      Column_distribution_pt = 0;
    }

References Column_distribution_pt, and Oomph_matrix_pt.

MatrixVectorProduct() [2/2]

oomph::MatrixVectorProduct::MatrixVectorProduct ( const MatrixVectorProduct &  )

delete

Broken copy constructor.

~MatrixVectorProduct()

oomph::MatrixVectorProduct::~MatrixVectorProduct ( )

inline

Destructor.

    {
      this->clean_up_memory();
    }

References clean_up_memory().

Member Function Documentation

clean_up_memory()

void oomph::MatrixVectorProduct::clean_up_memory ( )

inline

clear the memory

    {
#ifdef OOMPH_HAS_TRILINOS
      delete Epetra_matrix_pt;
      Epetra_matrix_pt = 0;
#endif
      delete Oomph_matrix_pt;
      Oomph_matrix_pt = 0;
      delete Column_distribution_pt;
      Column_distribution_pt = 0;
    }

References Column_distribution_pt, and Oomph_matrix_pt.

Referenced by oomph::PseudoElasticFSIPreconditioner::clean_up_memory(), setup(), and ~MatrixVectorProduct().

multiply()

void oomph::MatrixVectorProduct::multiply	(	const DoubleVector &	x,
		DoubleVector &	y
	)		const

Apply the operator to the vector x and return the result in the vector y

  {
#ifdef PARANOID
    // check that the distribution of x is setup
    if (!x.built())
    {
      std::ostringstream error_message_stream;
      error_message_stream << "The distribution of the vector x must be setup";
      throw OomphLibError(error_message_stream.str(),
                          OOMPH_CURRENT_FUNCTION,
                          OOMPH_EXCEPTION_LOCATION);
    }
 
    // Check to see if the distribution of the matrix column is the same as the
    // distribution of the vector to be operated on.
    if (*this->Column_distribution_pt != *x.distribution_pt())
    {
      std::ostringstream error_message_stream;
      error_message_stream
        << "The distribution of the x Vector is not the same as"
        << " the column distribution.";
      throw OomphLibError(error_message_stream.str(),
                          OOMPH_CURRENT_FUNCTION,
                          OOMPH_EXCEPTION_LOCATION);
    }
 
    // if y is setup then it should have the same distribution as
    // the matrix used to set this up.
    if (y.built())
    {
      if (!(*y.distribution_pt() == *this->distribution_pt()))
      {
        std::ostringstream error_message_stream;
        error_message_stream
          << "The y vector is setup and therefore must have the same "
          << "distribution as the matrix used to set up the "
             "MatrixVectorProduct";
        throw OomphLibError(error_message_stream.str(),
                            OOMPH_CURRENT_FUNCTION,
                            OOMPH_EXCEPTION_LOCATION);
      }
    }
#endif
 
    // if y is not setup then setup the distribution
    if (!y.built())
    {
      // Resize and initialize the solution vector
      y.build(this->distribution_pt(), 0.0);
    }
 
    // apply the operator
    if (Using_trilinos)
    {
#ifdef OOMPH_HAS_TRILINOS
      trilinos_multiply_helper(x, y);
#endif
    }
    else
    {
      Oomph_matrix_pt->multiply(x, y);
    }
  }

References Column_distribution_pt, oomph::DistributableLinearAlgebraObject::distribution_pt(), oomph::CRDoubleMatrix::multiply(), OOMPH_CURRENT_FUNCTION, OOMPH_EXCEPTION_LOCATION, Oomph_matrix_pt, Using_trilinos, plotDoE::x, and y.

Referenced by oomph::FSIPreconditioner::preconditioner_solve(), oomph::PseudoElasticFSIPreconditioner::preconditioner_solve(), oomph::PressureBasedSolidLSCPreconditioner::preconditioner_solve(), and oomph::SpaceTimeNavierStokesSubsidiaryPreconditioner::preconditioner_solve().

multiply_transpose()

void oomph::MatrixVectorProduct::multiply_transpose	(	const DoubleVector &	x,
		DoubleVector &	y
	)		const

Apply the transpose of the operator to the vector x and return the result in the vector y

  {
#ifdef PARANOID
    // check that the distribution of x is setup
    if (!x.built())
    {
      std::ostringstream error_message_stream;
      error_message_stream << "The distribution of the vector x must be setup";
      throw OomphLibError(error_message_stream.str(),
                          OOMPH_CURRENT_FUNCTION,
                          OOMPH_EXCEPTION_LOCATION);
    }
    // Check to see if x.size() = ncol()
    if (*this->distribution_pt() != *x.distribution_pt())
    {
      std::ostringstream error_message_stream;
      error_message_stream
        << "This class assumes that the y vector has a uniform "
        << "distributed distribution.";
      throw OomphLibError(error_message_stream.str(),
                          OOMPH_CURRENT_FUNCTION,
                          OOMPH_EXCEPTION_LOCATION);
    }
    // if y is setup then it should have the same distribution as x
    if (y.built())
    {
      if (!(*y.distribution_pt() == *this->Column_distribution_pt))
      {
        std::ostringstream error_message_stream;
        error_message_stream
          << "The y vector is setup and therefore must have the same "
          << "distribution as the vector x";
        throw OomphLibError(error_message_stream.str(),
                            OOMPH_CURRENT_FUNCTION,
                            OOMPH_EXCEPTION_LOCATION);
      }
    }
#endif
 
    // if y is not setup then setup the distribution
    if (!y.built())
    {
      // Resize and initialize the solution vector
      y.build(this->Column_distribution_pt, 0.0);
    }
 
    // apply the transpose operator
    if (Using_trilinos)
    {
#ifdef OOMPH_HAS_TRILINOS
      trilinos_multiply_transpose_helper(x, y);
#endif
    }
    else
    {
      Oomph_matrix_pt->multiply_transpose(x, y);
    }
  }

References Column_distribution_pt, oomph::DistributableLinearAlgebraObject::distribution_pt(), oomph::CRDoubleMatrix::multiply_transpose(), OOMPH_CURRENT_FUNCTION, OOMPH_EXCEPTION_LOCATION, Oomph_matrix_pt, Using_trilinos, plotDoE::x, and y.

Referenced by oomph::PressureBasedSolidLSCPreconditioner::preconditioner_solve(), and oomph::SpaceTimeNavierStokesSubsidiaryPreconditioner::preconditioner_solve().

ncol()

const unsigned& oomph::MatrixVectorProduct::ncol ( ) const

inline

Access function to the number of columns.

    {
      return Ncol;
    }

References Ncol.

operator=()

void oomph::MatrixVectorProduct::operator= ( const MatrixVectorProduct &  )

delete

Broken assignment operator.

setup()

void oomph::MatrixVectorProduct::setup	(	CRDoubleMatrix *	matrix_pt,
		const LinearAlgebraDistribution *	col_dist_pt = 0
	)

Setup the matrix vector product operator. WARNING: This class is wrapper to Trilinos Epetra matrix vector multiply methods, if Trilinos is not installed then this class will function as expected, but there will be no computational speed gain. By default the Epetra_CrsMatrix::multiply(...) are employed. The optional argument col_dist_pt is the distribution of: x if using multiply(...) or y if using multiply_transpose(...) where this is A x = y. By default, this is assumed to the uniformly distributed based on matrix_pt->ncol().

  {
    // clean memory
    this->clean_up_memory();
 
    // (re)build distribution_pt
    this->build_distribution(matrix_pt->distribution_pt());
 
    // store the number of columns
    Ncol = matrix_pt->ncol();
 
    // determine whether we are using trilinos
    Using_trilinos = false;
#ifdef OOMPH_HAS_TRILINOS
#ifdef OOMPH_HAS_MPI
    if (MPI_Helpers::mpi_has_been_initialised())
    {
      Using_trilinos = true;
    }
#else
    Using_trilinos = true;
#endif
#endif
 
    // create the column distribution map, if a distribution is not provided,
    // create a uniformly distributed based on matrix_pt->ncol().
    // Otherwise, use the provided distribution.
    if (col_dist_pt == 0)
    {
      Column_distribution_pt = new LinearAlgebraDistribution(
        matrix_pt->distribution_pt()->communicator_pt(),
        matrix_pt->ncol(),
        matrix_pt->distribution_pt()->distributed());
    }
    else
    {
      Column_distribution_pt = new LinearAlgebraDistribution(col_dist_pt);
    }
 
    // setup the operator
    if (Using_trilinos)
    {
#ifdef OOMPH_HAS_TRILINOS
      double t_start = TimingHelpers::timer();
      Epetra_matrix_pt =
        TrilinosEpetraHelpers::create_distributed_epetra_matrix(
          matrix_pt, Column_distribution_pt);
      double t_end = TimingHelpers::timer();
      oomph_info << "Time to build epetra matrix [sec] : " << t_end - t_start
                 << std::endl;
#endif
    }
    else
    {
      double t_start = TimingHelpers::timer();
      Oomph_matrix_pt = new CRDoubleMatrix(*matrix_pt);
      double t_end = TimingHelpers::timer();
      oomph_info << "Time to copy CRDoubleMatrix [sec] : " << t_end - t_start
                 << std::endl;
    }
  }

References oomph::DistributableLinearAlgebraObject::build_distribution(), clean_up_memory(), Column_distribution_pt, oomph::LinearAlgebraDistribution::communicator_pt(), oomph::TrilinosEpetraHelpers::create_distributed_epetra_matrix(), oomph::LinearAlgebraDistribution::distributed(), oomph::DistributableLinearAlgebraObject::distribution_pt(), oomph::MPI_Helpers::mpi_has_been_initialised(), oomph::CRDoubleMatrix::ncol(), Ncol, oomph::oomph_info, Oomph_matrix_pt, oomph::TimingHelpers::timer(), and Using_trilinos.

Referenced by oomph::BlockPreconditioner< MATRIX >::setup_matrix_vector_product().

Member Data Documentation

Column_distribution_pt

LinearAlgebraDistribution* oomph::MatrixVectorProduct::Column_distribution_pt

private

The distribution of: x if using multiply(...) or y if using multiply_transpose(...) where this is A x = y.

Referenced by clean_up_memory(), MatrixVectorProduct(), multiply(), multiply_transpose(), and setup().

Ncol

unsigned oomph::MatrixVectorProduct::Ncol

private

number of columns of the matrix

Referenced by ncol(), and setup().

Oomph_matrix_pt

CRDoubleMatrix* oomph::MatrixVectorProduct::Oomph_matrix_pt

private

an oomph-lib matrix

Referenced by clean_up_memory(), MatrixVectorProduct(), multiply(), multiply_transpose(), and setup().

Using_trilinos

bool oomph::MatrixVectorProduct::Using_trilinos

private

boolean indicating whether we are using trilinos to perform matvec

Referenced by multiply(), multiply_transpose(), and setup().

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

• matrix_vector_product.h
• matrix_vector_product.cc