Ifpack2_Details_InverseDiagonalKernel_decl.hpp

// @HEADER
// *****************************************************************************
//       Ifpack2: Templated Object-Oriented Algebraic Preconditioner Package
//
// Copyright 2009 NTESS and the Ifpack2 contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
// @HEADER


#ifndef IFPACK2_DETAILS_INVERSEDIAGONALKERNEL_DECL_HPP
#define IFPACK2_DETAILS_INVERSEDIAGONALKERNEL_DECL_HPP

#include "Ifpack2_config.h"
#include "Tpetra_CrsMatrix_fwd.hpp"
#include "Tpetra_MultiVector_fwd.hpp"
#include "Tpetra_Operator_fwd.hpp"
#include "Tpetra_Vector_fwd.hpp"
#include "Tpetra_Export_fwd.hpp"
#include "Tpetra_Import_fwd.hpp"
#include "Teuchos_RCP.hpp"
#include <memory>

namespace Ifpack2 {
namespace Details {

template<class TpetraOperatorType>
class InverseDiagonalKernel {
private:
  using SC = typename TpetraOperatorType::scalar_type;
  using LO = typename TpetraOperatorType::local_ordinal_type;
  using GO = typename TpetraOperatorType::global_ordinal_type;
  using NT = typename TpetraOperatorType::node_type;

  using crs_matrix_type = Tpetra::CrsMatrix<SC, LO, GO, NT>;
  using multivector_type = Tpetra::MultiVector<SC, LO, GO, NT>;
  using operator_type = Tpetra::Operator<SC, LO, GO, NT>;
  using vector_type = Tpetra::Vector<SC, LO, GO, NT>;
  using magnitude_type = typename Teuchos::ScalarTraits<SC>::magnitudeType;
  using device_type = typename NT::device_type;
  using offset_type = Kokkos::View<size_t*, device_type>;

public:
  InverseDiagonalKernel (const Teuchos::RCP<const operator_type>& A);

  void
  setMatrix (const Teuchos::RCP<const operator_type>& A);

  void
  compute (vector_type& D_inv,
           bool do_l1, magnitude_type L1Eta,
           bool fixTinyDiagEntries, magnitude_type MinDiagonalValue);

private:
  Teuchos::RCP<const operator_type> A_op_;
  Teuchos::RCP<const crs_matrix_type> A_crs_;
  offset_type offsets_;

};

} // namespace Details
} // namespace Ifpack2

#endif // IFPACK2_DETAILS_INVERSEINVERSEDIAGONALKERNEL_DECL_HPP