PreconditionerJacobi.hpp

/*
 * ------------------------------------------------------------------------------------------------------------
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 * Copyright (c) 2018-2019 Lawrence Livermore National Security LLC
 * Copyright (c) 2018-2019 The Board of Trustees of the Leland Stanford Junior University
 * Copyright (c) 2018-2019 Total, S.A
 * Copyright (c) 2019-     GEOSX Contributors
 * All right reserved
 *
 * See top level LICENSE, COPYRIGHT, CONTRIBUTORS, NOTICE, and ACKNOWLEDGEMENTS files for details.
 * ------------------------------------------------------------------------------------------------------------
 */

#ifndef GEOSX_LINEARALGEBRA_SOLVERS_PRECONDITIONERJACOBI_HPP_
#define GEOSX_LINEARALGEBRA_SOLVERS_PRECONDITIONERJACOBI_HPP_

#include "linearAlgebra/interfaces/LinearOperator.hpp"
#include "linearAlgebra/solvers/PreconditionerBase.hpp"

namespace geosx
{

template< typename LAI >
class PreconditionerJacobi : public PreconditionerBase< LAI >
{
public:

  using Base = PreconditionerBase< LAI >;

  using Vector = typename Base::Vector;

  using Matrix = typename Base::Matrix;

  virtual void compute( Matrix const & mat ) override
  {
    GEOSX_LAI_ASSERT( mat.ready() );
    m_diagInv.createWithLocalSize( mat.numLocalRows(), mat.getComm() );
    mat.extractDiagonal( m_diagInv );
    m_diagInv.reciprocal();
  }

  virtual void compute( Matrix const & mat,
                        DofManager const & dofManager ) override
  {
    GEOSX_UNUSED_VAR( dofManager );
    compute( mat );
  }

  virtual void clear() override
  {
    m_diagInv.reset();
  }

  virtual globalIndex numGlobalRows() const override final
  {
    GEOSX_LAI_ASSERT( m_diagInv.ready() );
    return m_diagInv.globalSize();
  }

  virtual globalIndex numGlobalCols() const override final
  {
    GEOSX_LAI_ASSERT( m_diagInv.ready() );
    return m_diagInv.globalSize();
  }

  virtual void apply( Vector const & src,
                      Vector & dst ) const override
  {
    GEOSX_LAI_ASSERT( m_diagInv.ready() );
    GEOSX_LAI_ASSERT_EQ( this->numGlobalRows(), dst.globalSize() );
    GEOSX_LAI_ASSERT_EQ( this->numGlobalCols(), src.globalSize() );

    m_diagInv.pointwiseProduct( src, dst );
  }

private:

  Vector m_diagInv;
};

}

#endif //GEOSX_LINEARALGEBRA_SOLVERS_PRECONDITIONERJACOBI_HPP_