PreconditionerJacobi.hpp

/*
 * ------------------------------------------------------------------------------------------------------------
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 * Copyright (c) 2016-2024 Lawrence Livermore National Security LLC
 * Copyright (c) 2018-2024 Total, S.A
 * Copyright (c) 2018-2024 The Board of Trustees of the Leland Stanford Junior University
 * Copyright (c) 2023-2024 Chevron
 * Copyright (c) 2019-     GEOS/GEOSX Contributors
 * All rights reserved
 *
 * See top level LICENSE, COPYRIGHT, CONTRIBUTORS, NOTICE, and ACKNOWLEDGEMENTS files for details.
 * ------------------------------------------------------------------------------------------------------------
 */
 
#ifndef GEOS_LINEARALGEBRA_SOLVERS_PRECONDITIONERJACOBI_HPP_
#define GEOS_LINEARALGEBRA_SOLVERS_PRECONDITIONERJACOBI_HPP_
 
#include "linearAlgebra/common/LinearOperator.hpp"
#include "linearAlgebra/common/PreconditionerBase.hpp"
 
namespace geos
{
 
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 setup( Matrix const & mat ) override
  {
    GEOS_LAI_ASSERT( mat.ready() );
    m_diagInv.createWithLocalSize( mat.numLocalRows(), mat.comm() );
    mat.extractDiagonal( m_diagInv );
    m_diagInv.reciprocal();
  }
 
  virtual void clear() override
  {
    m_diagInv.reset();
  }
 
  virtual globalIndex numGlobalRows() const override final
  {
    GEOS_LAI_ASSERT( m_diagInv.ready() );
    return m_diagInv.globalSize();
  }
 
  virtual globalIndex numGlobalCols() const override final
  {
    GEOS_LAI_ASSERT( m_diagInv.ready() );
    return m_diagInv.globalSize();
  }
 
  virtual void apply( Vector const & src,
                      Vector & dst ) const override
  {
    GEOS_LAI_ASSERT( m_diagInv.ready() );
    GEOS_LAI_ASSERT_EQ( this->numGlobalRows(), dst.globalSize() );
    GEOS_LAI_ASSERT_EQ( this->numGlobalCols(), src.globalSize() );
 
    m_diagInv.pointwiseProduct( src, dst );
  }
 
private:
 
  Vector m_diagInv;
};
 
}
 
#endif //GEOS_LINEARALGEBRA_SOLVERS_PRECONDITIONERJACOBI_HPP_