MueLu_ThresholdAFilterFactory_def.hpp

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#ifndef MUELU_THRESHOLDAFILTERFACTORY_DEF_HPP
#define MUELU_THRESHOLDAFILTERFACTORY_DEF_HPP

#include <Xpetra_Matrix.hpp>
#include <Xpetra_CrsMatrixWrap.hpp>

#include "MueLu_ThresholdAFilterFactory_decl.hpp"

#include "MueLu_Level.hpp"
#include "MueLu_Monitor.hpp"

namespace MueLu {

  template <class Scalar, class LocalOrdinal, class GlobalOrdinal, class Node>
  ThresholdAFilterFactory<Scalar, LocalOrdinal, GlobalOrdinal, Node>::ThresholdAFilterFactory(const std::string& ename, const Scalar threshold, const bool keepDiagonal, const GlobalOrdinal expectedNNZperRow)
    : varName_(ename), threshold_(threshold), keepDiagonal_(keepDiagonal), expectedNNZperRow_(expectedNNZperRow)
  { }

  template <class Scalar, class LocalOrdinal, class GlobalOrdinal, class Node>
  void ThresholdAFilterFactory<Scalar, LocalOrdinal, GlobalOrdinal, Node>::DeclareInput(Level &currentLevel) const {
    Input(currentLevel, varName_);
  }

  template <class Scalar, class LocalOrdinal, class GlobalOrdinal, class Node>
  void ThresholdAFilterFactory<Scalar, LocalOrdinal, GlobalOrdinal, Node>::
  Build (Level & currentLevel) const
  {
    FactoryMonitor m (*this, "A filter (thresholding)", currentLevel);

    RCP<Matrix> Ain = Get< RCP<Matrix> >(currentLevel, varName_);
    RCP<CrsMatrixWrap> Aout =
            MueLu::Utilities<Scalar, LocalOrdinal, GlobalOrdinal, Node>::GetThresholdedMatrix(Ain, threshold_, keepDiagonal_, expectedNNZperRow_);

    GetOStream(Statistics0) << "Nonzeros in " << varName_ << "(input): " << Ain->getGlobalNumEntries() << ", Nonzeros after filtering " << varName_ << " (parameter: " << threshold_ << "): " << Aout->getGlobalNumEntries() << std::endl;
    currentLevel.Set(varName_, Teuchos::rcp_dynamic_cast<Matrix>(Aout), this);
  }

} // namespace MueLu

#endif // MUELU_THRESHOLDAFILTERFACTORY_DEF_HPP