MueLu_Ifpack2Smoother_def.hpp

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#ifndef MUELU_IFPACK2SMOOTHER_DEF_HPP
#define MUELU_IFPACK2SMOOTHER_DEF_HPP
 
#include "MueLu_ConfigDefs.hpp"
 
#if defined(HAVE_MUELU_IFPACK2)
 
#include <Teuchos_ParameterList.hpp>
 
#include <Tpetra_RowMatrix.hpp>
 
#include <Ifpack2_Chebyshev.hpp>
#include <Ifpack2_RILUK.hpp>
#include <Ifpack2_Relaxation.hpp>
#include <Ifpack2_ILUT.hpp>
#include <Ifpack2_BlockRelaxation.hpp>
#include <Ifpack2_Factory.hpp>
#include <Ifpack2_Parameters.hpp>
 
#include <Xpetra_BlockedCrsMatrix.hpp>
#include <Xpetra_CrsMatrix.hpp>
#include <Xpetra_CrsMatrixWrap.hpp>
#include <Xpetra_TpetraBlockCrsMatrix.hpp>
#include <Xpetra_Matrix.hpp>
#include <Xpetra_MatrixMatrix.hpp>
#include <Xpetra_MultiVectorFactory.hpp>
#include <Xpetra_TpetraMultiVector.hpp>
 
#include <Tpetra_BlockCrsMatrix_Helpers.hpp>
 
#include "MueLu_Ifpack2Smoother_decl.hpp"
#include "MueLu_Level.hpp"
#include "MueLu_Utilities.hpp"
#include "MueLu_Monitor.hpp"
#include "MueLu_Aggregates.hpp"
 
 
#ifdef HAVE_MUELU_INTREPID2
#include "MueLu_IntrepidPCoarsenFactory_decl.hpp"
#include "MueLu_IntrepidPCoarsenFactory_def.hpp"
#include "Intrepid2_Basis.hpp"
#include "Kokkos_DynRankView.hpp"
#endif
 
 
namespace MueLu {
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::Ifpack2Smoother(const std::string& type, const Teuchos::ParameterList& paramList, const LO& overlap)
    : type_(type), overlap_(overlap)
  {
    typedef Tpetra::RowMatrix<SC,LO,GO,NO> tRowMatrix;
    bool isSupported = Ifpack2::Factory::isSupported<tRowMatrix>(type_) || (type_ == "LINESMOOTHING_TRIDI_RELAXATION"        ||
                                                                            type_ == "LINESMOOTHING_TRIDI RELAXATION"        ||
                                                                            type_ == "LINESMOOTHING_TRIDIRELAXATION"         ||
                                                                            type_ == "LINESMOOTHING_TRIDIAGONAL_RELAXATION"  ||
                                                                            type_ == "LINESMOOTHING_TRIDIAGONAL RELAXATION"  ||
                                                                            type_ == "LINESMOOTHING_TRIDIAGONALRELAXATION"   ||
                                                                            type_ == "LINESMOOTHING_BANDED_RELAXATION"       ||
                                                                            type_ == "LINESMOOTHING_BANDED RELAXATION"       ||
                                                                            type_ == "LINESMOOTHING_BANDEDRELAXATION"        ||
                                                                            type_ == "LINESMOOTHING_BLOCK_RELAXATION"        ||
                                                                            type_ == "LINESMOOTHING_BLOCK RELAXATION"        ||
                                                                            type_ == "LINESMOOTHING_BLOCKRELAXATION"         ||
                                                                            type_ == "TOPOLOGICAL"                           ||
                                                                            type_ == "AGGREGATE");
    this->declareConstructionOutcome(!isSupported, "Ifpack2 does not provide the smoother '" + type_ + "'.");
    if (isSupported)
      SetParameterList(paramList);
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetParameterList(const Teuchos::ParameterList& paramList) {
    Factory::SetParameterList(paramList);
 
    if (SmootherPrototype::IsSetup()) {
      // It might be invalid to change parameters after the setup, but it depends entirely on Ifpack implementation.
      // TODO: I don't know if Ifpack returns an error code or exception or ignore parameters modification in this case...
      SetPrecParameters();
    }
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetPrecParameters(const Teuchos::ParameterList& list) const {
    std::string prefix = this->ShortClassName() + ": SetPrecParameters";
    RCP<TimeMonitor> tM = rcp(new TimeMonitor(*this, prefix, Timings0));
    ParameterList& paramList = const_cast<ParameterList&>(this->GetParameterList());
 
    paramList.setParameters(list);
 
    RCP<ParameterList> precList = this->RemoveFactoriesFromList(this->GetParameterList());
 
    // Do we want an Ifpack2 apply timer?
    precList->set("timer for apply", this->IsPrint(Timings));
 
    if(!precList.is_null() && precList->isParameter("partitioner: type") && precList->get<std::string>("partitioner: type") == "linear" &&
       !precList->isParameter("partitioner: local parts")) {
      LO matrixBlockSize = 1;
      int lclSize = A_->getRangeMap()->getLocalNumElements();
      RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_);
      if (!matA.is_null()) {
        lclSize = matA->getLocalNumRows();
        matrixBlockSize = matA->GetFixedBlockSize();
      }
      precList->set("partitioner: local parts", lclSize / matrixBlockSize);
    }
 
    prec_->setParameters(*precList);
 
    paramList.setParameters(*precList); // what about that??
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::DeclareInput(Level& currentLevel) const {
    this->Input(currentLevel, "A");
 
    if (type_ == "LINESMOOTHING_TRIDI_RELAXATION"        ||
        type_ == "LINESMOOTHING_TRIDI RELAXATION"        ||
        type_ == "LINESMOOTHING_TRIDIRELAXATION"         ||
        type_ == "LINESMOOTHING_TRIDIAGONAL_RELAXATION"  ||
        type_ == "LINESMOOTHING_TRIDIAGONAL RELAXATION"  ||
        type_ == "LINESMOOTHING_TRIDIAGONALRELAXATION"   ||
        type_ == "LINESMOOTHING_BANDED_RELAXATION"       ||
        type_ == "LINESMOOTHING_BANDED RELAXATION"       ||
        type_ == "LINESMOOTHING_BANDEDRELAXATION"        ||
        type_ == "LINESMOOTHING_BLOCK_RELAXATION"        ||
        type_ == "LINESMOOTHING_BLOCK RELAXATION"        ||
        type_ == "LINESMOOTHING_BLOCKRELAXATION") {
      this->Input(currentLevel, "CoarseNumZLayers");            // necessary for fallback criterion
      this->Input(currentLevel, "LineDetection_VertLineIds");   // necessary to feed block smoother
    }
    else if (type_ == "BLOCK RELAXATION" ||
             type_ == "BLOCK_RELAXATION" ||
             type_ == "BLOCKRELAXATION" ||
             // Banded
             type_ == "BANDED_RELAXATION" ||
             type_ == "BANDED RELAXATION" ||
             type_ == "BANDEDRELAXATION" ||
             // Tridiagonal
             type_ == "TRIDI_RELAXATION" ||
             type_ == "TRIDI RELAXATION" ||
             type_ == "TRIDIRELAXATION" ||
             type_ == "TRIDIAGONAL_RELAXATION" ||
             type_ == "TRIDIAGONAL RELAXATION" ||
             type_ == "TRIDIAGONALRELAXATION")
    {
      //We need to check for the "partitioner type" = "line"
      ParameterList precList = this->GetParameterList();
      if(precList.isParameter("partitioner: type") &&
         precList.get<std::string>("partitioner: type") == "line") {
        this->Input(currentLevel, "Coordinates");
      }
    }
    else if (type_ == "TOPOLOGICAL")
    {
      // for the topological smoother, we require an element to node map:
      this->Input(currentLevel, "pcoarsen: element to node map");
    }
    else if (type_ == "AGGREGATE")
    {
      // Aggregate smoothing needs aggregates
      this->Input(currentLevel,"Aggregates");
    }
    else if (type_ == "HIPTMAIR") {
      // Hiptmair needs D0 and NodeMatrix
      this->Input(currentLevel,"NodeMatrix");
      this->Input(currentLevel,"D0");
    }
 
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::Setup(Level& currentLevel) {
    FactoryMonitor m(*this, "Setup Smoother", currentLevel);
    A_ = Factory::Get< RCP<Operator> >(currentLevel, "A");
    ParameterList& paramList = const_cast<ParameterList&>(this->GetParameterList());
 
    // If the user asked us to convert the matrix into BlockCrsMatrix form, we do that now
 
    if(paramList.isParameter("smoother: use blockcrsmatrix storage") && paramList.get<bool>("smoother: use blockcrsmatrix storage")) {
      int blocksize = 1;
      RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_);
      if (!matA.is_null())
        blocksize = matA->GetFixedBlockSize();
      if (blocksize) {
        // NOTE: Don't think you can move this out of the if block.  You can't. The test MueLu_MeshTyingBlocked_SimpleSmoother_2dof_medium_MPI_1 will fail
 
        RCP<CrsMatrixWrap> AcrsWrap = rcp_dynamic_cast<CrsMatrixWrap>(A_);
        if(AcrsWrap.is_null())
          throw std::runtime_error("Ifpack2Smoother: Cannot convert matrix A to CrsMatrixWrap object.");
        RCP<CrsMatrix> Acrs =  AcrsWrap->getCrsMatrix();
        if(Acrs.is_null())
          throw std::runtime_error("Ifpack2Smoother: Cannot extract CrsMatrix from matrix A.");
        RCP<TpetraCrsMatrix> At = rcp_dynamic_cast<TpetraCrsMatrix>(Acrs);
        if(At.is_null()) {
          if(!Xpetra::Helpers<Scalar,LO,GO,Node>::isTpetraBlockCrs(matA))
            throw std::runtime_error("Ifpack2Smoother: Cannot extract CrsMatrix or BlockCrsMatrix from matrix A.");
          this->GetOStream(Statistics0) << "Ifpack2Smoother: Using (native) BlockCrsMatrix storage with blocksize "<<blocksize<<std::endl;
          paramList.remove("smoother: use blockcrsmatrix storage");
        }
        else {
          RCP<Tpetra::BlockCrsMatrix<Scalar, LO, GO, Node> > blockCrs = Tpetra::convertToBlockCrsMatrix(*At->getTpetra_CrsMatrix(),blocksize);
          RCP<CrsMatrix> blockCrs_as_crs  = rcp(new TpetraBlockCrsMatrix(blockCrs));
          RCP<CrsMatrixWrap> blockWrap = rcp(new CrsMatrixWrap(blockCrs_as_crs));
          A_ = blockWrap;
          this->GetOStream(Statistics0) << "Ifpack2Smoother: Using BlockCrsMatrix storage with blocksize "<<blocksize<<std::endl;
          
          paramList.remove("smoother: use blockcrsmatrix storage");
        }
      }
    }
 
    if      (type_ == "SCHWARZ")
      SetupSchwarz(currentLevel);
 
    else if (type_ == "LINESMOOTHING_TRIDI_RELAXATION"       ||
             type_ == "LINESMOOTHING_TRIDI RELAXATION"       ||
             type_ == "LINESMOOTHING_TRIDIRELAXATION"        ||
             type_ == "LINESMOOTHING_TRIDIAGONAL_RELAXATION" ||
             type_ == "LINESMOOTHING_TRIDIAGONAL RELAXATION" ||
             type_ == "LINESMOOTHING_TRIDIAGONALRELAXATION"  ||
             type_ == "LINESMOOTHING_BANDED_RELAXATION"      ||
             type_ == "LINESMOOTHING_BANDED RELAXATION"      ||
             type_ == "LINESMOOTHING_BANDEDRELAXATION"       ||
             type_ == "LINESMOOTHING_BLOCK_RELAXATION"       ||
             type_ == "LINESMOOTHING_BLOCK RELAXATION"       ||
             type_ == "LINESMOOTHING_BLOCKRELAXATION")
      SetupLineSmoothing(currentLevel);
 
    else if (type_ == "BLOCK_RELAXATION" ||
             type_ == "BLOCK RELAXATION" ||
             type_ == "BLOCKRELAXATION" ||
             // Banded
             type_ == "BANDED_RELAXATION" ||
             type_ == "BANDED RELAXATION" ||
             type_ == "BANDEDRELAXATION" ||
             // Tridiagonal
             type_ == "TRIDI_RELAXATION" ||
             type_ == "TRIDI RELAXATION" ||
             type_ == "TRIDIRELAXATION" ||
             type_ == "TRIDIAGONAL_RELAXATION" ||
             type_ == "TRIDIAGONAL RELAXATION" ||
             type_ == "TRIDIAGONALRELAXATION")
      SetupBlockRelaxation(currentLevel);
 
    else if (type_ == "CHEBYSHEV")
      SetupChebyshev(currentLevel);
 
    else if (type_ == "TOPOLOGICAL")
    {
#ifdef HAVE_MUELU_INTREPID2
      SetupTopological(currentLevel);
#else
      TEUCHOS_TEST_FOR_EXCEPTION(true, std::invalid_argument, "'TOPOLOGICAL' smoother choice requires Intrepid2");
#endif
    }
    else if (type_ == "AGGREGATE")
      SetupAggregate(currentLevel);
 
    else if (type_ == "HIPTMAIR")
      SetupHiptmair(currentLevel);
 
    else
    {
      SetupGeneric(currentLevel);
    }
 
    SmootherPrototype::IsSetup(true);
 
    this->GetOStream(Statistics1) << description() << std::endl;
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupSchwarz(Level& /* currentLevel */) {
    typedef Tpetra::RowMatrix<SC,LO,GO,NO> tRowMatrix;
 
    bool reusePreconditioner = false;
    if (this->IsSetup() == true) {
      // Reuse the constructed preconditioner
      this->GetOStream(Runtime1) << "MueLu::Ifpack2Smoother::SetupSchwarz(): Setup() has already been called, assuming reuse" << std::endl;
 
      bool isTRowMatrix = true;
      RCP<const tRowMatrix> tA;
      try {
        tA = Utilities::Op2NonConstTpetraRow(A_);
      } catch (Exceptions::BadCast&) {
        isTRowMatrix = false;
      }
 
      RCP<Ifpack2::Details::CanChangeMatrix<tRowMatrix> > prec = rcp_dynamic_cast<Ifpack2::Details::CanChangeMatrix<tRowMatrix> >(prec_);
      if (!prec.is_null() && isTRowMatrix) {
        prec->setMatrix(tA);
        reusePreconditioner = true;
      } else {
        this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupSchwarz(): reuse of this type is not available "
            "(either failed cast to CanChangeMatrix, or to Tpetra Row Matrix), reverting to full construction" << std::endl;
      }
    }
 
    if (!reusePreconditioner) {
      ParameterList& paramList = const_cast<ParameterList&>(this->GetParameterList());
 
      bool isBlockedMatrix = false;
      RCP<Matrix> merged2Mat;
 
      std::string sublistName = "subdomain solver parameters";
      if (paramList.isSublist(sublistName)) {
        // If we are doing "user" partitioning, we assume that what the user
        // really wants to do is make tiny little subdomains with one row
        // assigned to each subdomain. The rows used for these little
        // subdomains correspond to those in the 2nd block row. Then,
        // if we overlap these mini-subdomains, we will do something that
        // looks like Vanka (grabbing all velocities associated with each
        // each pressure unknown). In addition, we put all Dirichlet points
        // as a little mini-domain.
        ParameterList& subList = paramList.sublist(sublistName);
 
        std::string partName = "partitioner: type";
        // Pretty sure no one has been using this. Unfortunately, old if
        // statement (which checked for equality with "user") prevented
        // anyone from employing other types of Ifpack2 user partition
        // options. Leaving this and switching if to "vanka user" just
        // in case some day someone might want to use this.
        if (subList.isParameter(partName) && subList.get<std::string>(partName) == "vanka user") {
          isBlockedMatrix = true;
 
          RCP<BlockedCrsMatrix> bA = rcp_dynamic_cast<BlockedCrsMatrix>(A_);
          TEUCHOS_TEST_FOR_EXCEPTION(bA.is_null(), Exceptions::BadCast,
                                     "Matrix A must be of type BlockedCrsMatrix.");
 
          size_t numVels = bA->getMatrix(0,0)->getLocalNumRows();
          size_t numPres = bA->getMatrix(1,0)->getLocalNumRows();
          size_t numRows = rcp_dynamic_cast<Matrix>(A_, true)->getLocalNumRows();
 
          ArrayRCP<LocalOrdinal> blockSeeds(numRows, Teuchos::OrdinalTraits<LocalOrdinal>::invalid());
 
          size_t numBlocks = 0;
          for (size_t rowOfB = numVels; rowOfB < numVels+numPres; ++rowOfB)
            blockSeeds[rowOfB] = numBlocks++;
 
          RCP<BlockedCrsMatrix> bA2 = rcp_dynamic_cast<BlockedCrsMatrix>(A_);
          TEUCHOS_TEST_FOR_EXCEPTION(bA2.is_null(), Exceptions::BadCast,
                                     "Matrix A must be of type BlockedCrsMatrix.");
 
          merged2Mat = bA2->Merge();
 
          // Add Dirichlet rows to the list of seeds
          ArrayRCP<const bool> boundaryNodes = Utilities::DetectDirichletRows(*merged2Mat, 0.0);
          bool haveBoundary = false;
          for (LO i = 0; i < boundaryNodes.size(); i++)
            if (boundaryNodes[i]) {
              // FIXME:
              // 1. would not this [] overlap with some in the previos blockSeed loop?
              // 2. do we need to distinguish between pressure and velocity Dirichlet b.c.
              blockSeeds[i] = numBlocks;
              haveBoundary = true;
            }
          if (haveBoundary)
            numBlocks++;
 
          subList.set("partitioner: type","user");
          subList.set("partitioner: map",         blockSeeds);
          subList.set("partitioner: local parts", as<int>(numBlocks));
 
        } else {
          RCP<BlockedCrsMatrix> bA = rcp_dynamic_cast<BlockedCrsMatrix>(A_);
          if (!bA.is_null()) {
            isBlockedMatrix = true;
            merged2Mat = bA->Merge();
          }
        }
      }
 
      RCP<const tRowMatrix> tA;
      if (isBlockedMatrix == true) tA = Utilities::Op2NonConstTpetraRow(merged2Mat);
      else                         tA = Utilities::Op2NonConstTpetraRow(A_);
 
      prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
      SetPrecParameters();
 
      prec_->initialize();
    }
 
    prec_->compute();
  }
 
 
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupAggregate(Level& currentLevel) {
 
    ParameterList& paramList = const_cast<ParameterList&>(this->GetParameterList());
 
    if (this->IsSetup() == true) {
      this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupAggregate(): Setup() has already been called" << std::endl;
      this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupAggregate(): reuse of this type is not available, reverting to full construction" << std::endl;
    }
 
    this->GetOStream(Statistics0) << "Ifpack2Smoother: Using Aggregate Smoothing"<<std::endl;
 
    RCP<Aggregates> aggregates = Factory::Get<RCP<Aggregates> >(currentLevel,"Aggregates");
 
    RCP<const LOMultiVector> vertex2AggId = aggregates->GetVertex2AggId();
    ArrayRCP<LO> aggregate_ids = rcp_const_cast<LOMultiVector>(vertex2AggId)->getDataNonConst(0);
    ArrayRCP<LO> dof_ids;
 
    // We need to unamalgamate, if the FixedBlockSize > 1
    LO blocksize = 1;
    RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_);
    if (!matA.is_null())
      blocksize = matA->GetFixedBlockSize();
    if(blocksize > 1) {
      dof_ids.resize(aggregate_ids.size() * blocksize);
      for(LO i=0; i<(LO)aggregate_ids.size(); i++) {
        for(LO j=0; j<(LO)blocksize; j++)
          dof_ids[i*blocksize+j] = aggregate_ids[i];
      }
    }
    else {
      dof_ids = aggregate_ids;
    }
        
    
    paramList.set("partitioner: map", dof_ids);
    paramList.set("partitioner: type", "user");
    paramList.set("partitioner: overlap", 0);
    paramList.set("partitioner: local parts", (int)aggregates->GetNumAggregates());
 
    RCP<const Tpetra::RowMatrix<SC, LO, GO, NO> > tA = Utilities::Op2NonConstTpetraRow(A_);
    
    type_ = "BLOCKRELAXATION";
    prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
    SetPrecParameters();
    prec_->initialize();
    prec_->compute();
  }
 
#ifdef HAVE_MUELU_INTREPID2
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupTopological(Level& currentLevel) {
    /*
     
     basic notion:
     
     Look for user input indicating topo dimension, something like "topological domain type: {node|edge|face}"
     Call something like what you can find in Poisson example line 1180 to set seeds for a smoother
     
     */
    if (this->IsSetup() == true) {
      this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupTopological(): Setup() has already been called" << std::endl;
      this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupTopological(): reuse of this type is not available, reverting to full construction" << std::endl;
    }
    
    ParameterList& paramList = const_cast<ParameterList&>(this->GetParameterList());
    
    typedef typename Node::device_type::execution_space ES;
    
    typedef Kokkos::DynRankView<LocalOrdinal,typename Node::device_type> FCO; //
    
    LocalOrdinal  lo_invalid = Teuchos::OrdinalTraits<LO>::invalid();
    
    using namespace std;
    
    const Teuchos::RCP<FCO> elemToNode = Factory::Get<Teuchos::RCP<FCO> >(currentLevel,"pcoarsen: element to node map");
    
    string basisString = paramList.get<string>("pcoarsen: hi basis");
    int degree;
    // NOTE: To make sure Stokhos works we only instantiate these guys with double.  There's a lot
    // of stuff in the guts of Intrepid2 that doesn't play well with Stokhos as of yet.  Here, we only
    // care about the assignment of basis ordinals to topological entities, so this code is actually
    // independent of the Scalar type--hard-coding double here won't hurt us.
    auto basis = MueLuIntrepid::BasisFactory<double,ES>(basisString, degree);
    
    string topologyTypeString = paramList.get<string>("smoother: neighborhood type");
    int dimension;
    if (topologyTypeString == "node")
      dimension = 0;
    else if (topologyTypeString == "edge")
      dimension = 1;
    else if (topologyTypeString == "face")
      dimension = 2;
    else if (topologyTypeString == "cell")
      dimension = basis->getBaseCellTopology().getDimension();
    else
      TEUCHOS_TEST_FOR_EXCEPTION(true,std::invalid_argument,"Unrecognized smoother neighborhood type.  Supported types are node, edge, face.");
    RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_, true);
    vector<vector<LocalOrdinal>> seeds;
    MueLuIntrepid::FindGeometricSeedOrdinals(basis, *elemToNode, seeds, *matA->getRowMap(), *matA->getColMap());
    
    // Ifpack2 wants the seeds in an array of the same length as the number of local elements,
    // with local partition #s marked for the ones that are seeds, and invalid for the rest
    int myNodeCount = matA->getRowMap()->getLocalNumElements();
    ArrayRCP<LocalOrdinal> nodeSeeds(myNodeCount,lo_invalid);
    int localPartitionNumber = 0;
    for (LocalOrdinal seed : seeds[dimension])
    {
      nodeSeeds[seed] = localPartitionNumber++;
    }
    
    paramList.remove("smoother: neighborhood type");
    paramList.remove("pcoarsen: hi basis");
    
    paramList.set("partitioner: map", nodeSeeds);
    paramList.set("partitioner: type", "user");
    paramList.set("partitioner: overlap", 1);
    paramList.set("partitioner: local parts", int(seeds[dimension].size()));
 
    RCP<const Tpetra::RowMatrix<SC, LO, GO, NO> > tA = Utilities::Op2NonConstTpetraRow(A_);
    
    type_ = "BLOCKRELAXATION";
    prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
    SetPrecParameters();
    prec_->initialize();
    prec_->compute();
  }
#endif
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupLineSmoothing(Level& currentLevel) {
    if (this->IsSetup() == true) {
      this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupLineSmoothing(): Setup() has already been called" << std::endl;
      this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupLineSmoothing(): reuse of this type is not available, reverting to full construction" << std::endl;
    }
 
    ParameterList& myparamList = const_cast<ParameterList&>(this->GetParameterList());
 
    LO CoarseNumZLayers = Factory::Get<LO>(currentLevel,"CoarseNumZLayers");
    if (CoarseNumZLayers > 0) {
      Teuchos::ArrayRCP<LO> TVertLineIdSmoo = Factory::Get< Teuchos::ArrayRCP<LO> >(currentLevel, "LineDetection_VertLineIds");
 
      // determine number of local parts
      LO maxPart = 0;
      for(size_t k = 0; k < Teuchos::as<size_t>(TVertLineIdSmoo.size()); k++) {
        if(maxPart < TVertLineIdSmoo[k]) maxPart = TVertLineIdSmoo[k];
      }
      RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_, true);
      size_t numLocalRows = matA->getLocalNumRows();
 
      TEUCHOS_TEST_FOR_EXCEPTION(numLocalRows % TVertLineIdSmoo.size() != 0, Exceptions::RuntimeError,
        "MueLu::Ifpack2Smoother::Setup(): the number of local nodes is incompatible with the TVertLineIdsSmoo.");
 
      //actualDofsPerNode is the actual number of matrix rows per mesh element.
      //It is encoded in either the MueLu Level, or in the Xpetra matrix block size.
      //This value is needed by Ifpack2 to do decoupled block relaxation.
      int actualDofsPerNode = numLocalRows / TVertLineIdSmoo.size();
      LO matrixBlockSize = matA->GetFixedBlockSize();
      if(matrixBlockSize > 1 && actualDofsPerNode > 1)
      {
        TEUCHOS_TEST_FOR_EXCEPTION(actualDofsPerNode != matrixBlockSize, Exceptions::RuntimeError,
            "MueLu::Ifpack2Smoother::Setup(): A is a block matrix but its block size and DOFs/node from partitioner disagree");
      }
      else if(matrixBlockSize > 1)
      {
        actualDofsPerNode = matrixBlockSize;
      }
      myparamList.set("partitioner: PDE equations", actualDofsPerNode);
 
      if (numLocalRows == Teuchos::as<size_t>(TVertLineIdSmoo.size())) {
        myparamList.set("partitioner: type","user");
        myparamList.set("partitioner: map",TVertLineIdSmoo);
        myparamList.set("partitioner: local parts",maxPart+1);
      } else {
        // we assume a constant number of DOFs per node
        size_t numDofsPerNode = numLocalRows / TVertLineIdSmoo.size();
 
        // Create a new Teuchos::ArrayRCP<LO> of size numLocalRows and fill it with the corresponding information
        Teuchos::ArrayRCP<LO> partitionerMap(numLocalRows, Teuchos::OrdinalTraits<LocalOrdinal>::invalid());
        for (size_t blockRow = 0; blockRow < Teuchos::as<size_t>(TVertLineIdSmoo.size()); ++blockRow)
          for (size_t dof = 0; dof < numDofsPerNode; dof++)
            partitionerMap[blockRow * numDofsPerNode + dof] = TVertLineIdSmoo[blockRow];
        myparamList.set("partitioner: type","user");
        myparamList.set("partitioner: map",partitionerMap);
        myparamList.set("partitioner: local parts",maxPart + 1);
      }
 
      if (type_ == "LINESMOOTHING_BANDED_RELAXATION" ||
          type_ == "LINESMOOTHING_BANDED RELAXATION" ||
          type_ == "LINESMOOTHING_BANDEDRELAXATION")
        type_ = "BANDEDRELAXATION";
      else if (type_ == "LINESMOOTHING_TRIDI_RELAXATION"       ||
               type_ == "LINESMOOTHING_TRIDI RELAXATION"       ||
               type_ == "LINESMOOTHING_TRIDIRELAXATION"        ||
               type_ == "LINESMOOTHING_TRIDIAGONAL_RELAXATION" ||
               type_ == "LINESMOOTHING_TRIDIAGONAL RELAXATION" ||
               type_ == "LINESMOOTHING_TRIDIAGONALRELAXATION")
        type_ = "TRIDIAGONALRELAXATION";
      else
        type_ = "BLOCKRELAXATION";
    } else {
      // line detection failed -> fallback to point-wise relaxation
      this->GetOStream(Runtime0) << "Line detection failed: fall back to point-wise relaxation" << std::endl;
      myparamList.remove("partitioner: type",false);
      myparamList.remove("partitioner: map", false);
      myparamList.remove("partitioner: local parts",false);
      type_ = "RELAXATION";
    }
 
    RCP<const Tpetra::RowMatrix<SC, LO, GO, NO> > tA = Utilities::Op2NonConstTpetraRow(A_);
 
    prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
    SetPrecParameters();
    prec_->initialize();
    prec_->compute();
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupBlockRelaxation(Level& currentLevel) {
    typedef Tpetra::RowMatrix<SC,LO,GO,NO> tRowMatrix;
 
    RCP<BlockedCrsMatrix> bA = rcp_dynamic_cast<BlockedCrsMatrix>(A_);
    if (!bA.is_null())
      A_ = bA->Merge();
 
    RCP<const tRowMatrix> tA = Utilities::Op2NonConstTpetraRow(A_);
 
    bool reusePreconditioner = false;
    if (this->IsSetup() == true) {
      // Reuse the constructed preconditioner
      this->GetOStream(Runtime1) << "MueLu::Ifpack2Smoother::SetupBlockRelaxation(): Setup() has already been called, assuming reuse" << std::endl;
 
      RCP<Ifpack2::Details::CanChangeMatrix<tRowMatrix> > prec = rcp_dynamic_cast<Ifpack2::Details::CanChangeMatrix<tRowMatrix> >(prec_);
      if (!prec.is_null()) {
        prec->setMatrix(tA);
        reusePreconditioner = true;
      } else {
        this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupBlockRelaxation(): reuse of this type is not available (failed cast to CanChangeMatrix), "
            "reverting to full construction" << std::endl;
      }
    }
 
    if (!reusePreconditioner) {
      ParameterList& myparamList = const_cast<ParameterList&>(this->GetParameterList());
      myparamList.print();
      if(myparamList.isParameter("partitioner: type") &&
         myparamList.get<std::string>("partitioner: type") == "line") {
        Teuchos::RCP<Xpetra::MultiVector<typename Teuchos::ScalarTraits<Scalar>::magnitudeType,LO,GO,NO> > xCoordinates =
          Factory::Get<Teuchos::RCP<Xpetra::MultiVector<typename Teuchos::ScalarTraits<Scalar>::magnitudeType,LO,GO,NO> > >(currentLevel, "Coordinates");
        Teuchos::RCP<Tpetra::MultiVector<typename Teuchos::ScalarTraits<Scalar>::magnitudeType,LO,GO,NO> > coordinates = Teuchos::rcpFromRef(Xpetra::toTpetra<typename Teuchos::ScalarTraits<Scalar>::magnitudeType,LO,GO,NO>(*xCoordinates));
 
        RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_);
        size_t lclSize = A_->getRangeMap()->getLocalNumElements();
        if (!matA.is_null())
          lclSize = matA->getLocalNumRows();
        size_t numDofsPerNode = lclSize / xCoordinates->getMap()->getLocalNumElements();
        myparamList.set("partitioner: coordinates", coordinates);
        myparamList.set("partitioner: PDE equations", (int) numDofsPerNode);
      }
 
      prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
      SetPrecParameters();
      prec_->initialize();
    }
 
    prec_->compute();
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupChebyshev(Level& currentLevel) {
    typedef Tpetra::RowMatrix<SC,LO,GO,NO> tRowMatrix;
    using STS = Teuchos::ScalarTraits<SC>;
    RCP<BlockedCrsMatrix> bA = rcp_dynamic_cast<BlockedCrsMatrix>(A_);
    if (!bA.is_null())
      A_ = bA->Merge();
 
    RCP<const tRowMatrix> tA = Utilities::Op2NonConstTpetraRow(A_);
 
    bool reusePreconditioner = false;
 
    if (this->IsSetup() == true) {
      // Reuse the constructed preconditioner
      this->GetOStream(Runtime1) << "MueLu::Ifpack2Smoother::SetupChebyshev(): Setup() has already been called, assuming reuse" << std::endl;
 
      RCP<Ifpack2::Details::CanChangeMatrix<tRowMatrix> > prec = rcp_dynamic_cast<Ifpack2::Details::CanChangeMatrix<tRowMatrix> >(prec_);
      if (!prec.is_null()) {
        prec->setMatrix(tA);
        reusePreconditioner = true;
      } else {
        this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupChebyshev(): reuse of this type is not available (failed cast to CanChangeMatrix), "
            "reverting to full construction" << std::endl;
      }
    }
 
    // Take care of the eigenvalues
    ParameterList& paramList = const_cast<ParameterList&>(this->GetParameterList());
    SC negone = -STS::one();
    SC lambdaMax = SetupChebyshevEigenvalues(currentLevel,"A","",paramList);
 
 
    if (!reusePreconditioner) {
      prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
      SetPrecParameters();
      {
        SubFactoryMonitor(*this, "Preconditioner init", currentLevel);
        prec_->initialize();
      }
    } else
      SetPrecParameters();
 
    {
      SubFactoryMonitor(*this, "Preconditioner compute", currentLevel);
      prec_->compute();
    }
 
    if (lambdaMax == negone) {
      typedef Tpetra::RowMatrix<SC, LO, GO, NO> MatrixType;
 
      Teuchos::RCP<Ifpack2::Chebyshev<MatrixType> > chebyPrec = rcp_dynamic_cast<Ifpack2::Chebyshev<MatrixType> >(prec_);
      if (chebyPrec != Teuchos::null) {
        lambdaMax = chebyPrec->getLambdaMaxForApply();
        RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_);
        if (!matA.is_null())
          matA->SetMaxEigenvalueEstimate(lambdaMax);
        this->GetOStream(Statistics1) << "chebyshev: max eigenvalue (calculated by Ifpack2)" << " = " << lambdaMax << std::endl;
      }
      TEUCHOS_TEST_FOR_EXCEPTION(lambdaMax == negone, Exceptions::RuntimeError, "MueLu::Ifpack2Smoother::Setup(): no maximum eigenvalue estimate");
    }
  }
 
 
 template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupHiptmair(Level&  currentLevel ) {
    typedef Tpetra::RowMatrix<SC,LO,GO,NO> tRowMatrix;
    RCP<BlockedCrsMatrix> bA = rcp_dynamic_cast<BlockedCrsMatrix>(A_);
    if (!bA.is_null())
      A_ = bA->Merge();
 
    RCP<const tRowMatrix> tA = Utilities::Op2NonConstTpetraRow(A_);
 
    bool reusePreconditioner = false;
    if (this->IsSetup() == true) {
      // Reuse the constructed preconditioner
      this->GetOStream(Runtime1) << "MueLu::Ifpack2Smoother::SetupHiptmair(): Setup() has already been called, assuming reuse" << std::endl;
 
      RCP<Ifpack2::Details::CanChangeMatrix<tRowMatrix> > prec = rcp_dynamic_cast<Ifpack2::Details::CanChangeMatrix<tRowMatrix> >(prec_);
      if (!prec.is_null()) {
        prec->setMatrix(tA);
        reusePreconditioner = true;
      } else {
        this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupHiptmair(): reuse of this type is not available (failed cast to CanChangeMatrix), "
            "reverting to full construction" << std::endl;
      }
    }
 
    // If we're doing Chebyshev subsmoothing, we'll need to get the eigenvalues
    ParameterList& paramList = const_cast<ParameterList&>(this->GetParameterList());
    std::string smoother1  = paramList.get("hiptmair: smoother type 1","CHEBYSHEV");
    std::string smoother2  = paramList.get("hiptmair: smoother type 2","CHEBYSHEV");
    //    SC lambdaMax11,lambdaMax22;
 
    if(smoother1 == "CHEBYSHEV") {
      ParameterList & list1 = paramList.sublist("hiptmair: smoother list 1");
      //lambdaMax11 =
      SetupChebyshevEigenvalues(currentLevel,"A","EdgeMatrix ",list1);
    }
    if(smoother2 == "CHEBYSHEV") {
      ParameterList & list2 = paramList.sublist("hiptmair: smoother list 2");
      //lambdaMax22 =
      SetupChebyshevEigenvalues(currentLevel,"A","EdgeMatrix ",list2);
    }
 
    // FIXME: Should really add some checks to make sure the eigenvalue calcs worked like in
    // the regular SetupChebyshev
 
    // Grab the auxillary matrices and stick them on the list
    RCP<Operator> NodeMatrix = currentLevel.Get<RCP<Operator> >("NodeMatrix");
    RCP<Operator> D0         = currentLevel.Get<RCP<Operator> >("D0");
 
    RCP<tRowMatrix> tNodeMatrix = Utilities::Op2NonConstTpetraRow(NodeMatrix);
    RCP<tRowMatrix> tD0         = Utilities::Op2NonConstTpetraRow(D0);
 
 
    Teuchos::ParameterList newlist;
    newlist.set("P",tD0);
    newlist.set("PtAP",tNodeMatrix);
    if (!reusePreconditioner) {
      prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
      SetPrecParameters(newlist);
      prec_->initialize();
    }
 
    prec_->compute();
  }
 
 
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  Scalar Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupChebyshevEigenvalues(Level & currentLevel, const std::string & matrixName, const std::string & label, ParameterList & paramList) const {
    // Helper: This gets used for smoothers that want to set up Chebyhev
    typedef Teuchos::ScalarTraits<SC> STS;
    SC negone = -STS::one();
    RCP<const Matrix> currentA = currentLevel.Get<RCP<Matrix> >(matrixName);
    SC lambdaMax = negone;
 
    std::string maxEigString   = "chebyshev: max eigenvalue";
    std::string eigRatioString = "chebyshev: ratio eigenvalue";
    
    // Get/calculate the maximum eigenvalue
    if (paramList.isParameter(maxEigString)) {
      if (paramList.isType<double>(maxEigString))
        lambdaMax = paramList.get<double>(maxEigString);
      else
        lambdaMax = paramList.get<SC>(maxEigString);
      this->GetOStream(Statistics1) << label << maxEigString << " (cached with smoother parameter list) = " << lambdaMax << std::endl;
      RCP<Matrix> matA = rcp_dynamic_cast<Matrix>(A_);
      if (!matA.is_null())
        matA->SetMaxEigenvalueEstimate(lambdaMax);
      
    } else {
      lambdaMax = currentA->GetMaxEigenvalueEstimate();
      if (lambdaMax != negone) {
        this->GetOStream(Statistics1) << label << maxEigString << " (cached with matrix) = " << lambdaMax << std::endl;
        paramList.set(maxEigString, lambdaMax);
      }
    }
    
    // Calculate the eigenvalue ratio
    const SC defaultEigRatio = 20;
    
    SC ratio = defaultEigRatio;
    if (paramList.isParameter(eigRatioString)) {
      if (paramList.isType<double>(eigRatioString))
        ratio = paramList.get<double>(eigRatioString);
      else
          ratio = paramList.get<SC>(eigRatioString);
    }
    if (currentLevel.GetLevelID()) {
      // Update ratio to be
      //   ratio = max(number of fine DOFs / number of coarse DOFs, defaultValue)
      //
      // NOTE: We don't need to request previous level matrix as we know for sure it was constructed
      RCP<const Matrix> fineA = currentLevel.GetPreviousLevel()->Get<RCP<Matrix> >(matrixName);
      size_t nRowsFine   = fineA->getGlobalNumRows();
      size_t nRowsCoarse = currentA->getGlobalNumRows();
      
      SC levelRatio = as<SC>(as<float>(nRowsFine)/nRowsCoarse);
      if (STS::magnitude(levelRatio) > STS::magnitude(ratio))
        ratio = levelRatio;
    }
    
    this->GetOStream(Statistics1) << label << eigRatioString << " (computed) = " << ratio << std::endl;
    paramList.set(eigRatioString, ratio);
 
    if (paramList.isParameter("chebyshev: use rowsumabs diagonal scaling")) {
      this->GetOStream(Runtime1) << "chebyshev: using rowsumabs diagonal scaling" << std::endl;
      bool doScale = false;
      doScale = paramList.get<bool>("chebyshev: use rowsumabs diagonal scaling");
      paramList.remove("chebyshev: use rowsumabs diagonal scaling");
      double chebyReplaceTol = Teuchos::ScalarTraits<Scalar>::eps()*100;
      std::string paramName = "chebyshev: rowsumabs diagonal replacement tolerance";
      if (paramList.isParameter(paramName)) {
        chebyReplaceTol = paramList.get<double>(paramName);
        paramList.remove(paramName);
      }
      double chebyReplaceVal = Teuchos::ScalarTraits<double>::zero();
      paramName = "chebyshev: rowsumabs diagonal replacement value";
      if (paramList.isParameter(paramName)) {
        chebyReplaceVal = paramList.get<double>(paramName);
        paramList.remove(paramName);
      }
      bool chebyReplaceSingleEntryRowWithZero = false;
      paramName = "chebyshev: rowsumabs replace single entry row with zero";
      if (paramList.isParameter(paramName)) {
        chebyReplaceSingleEntryRowWithZero = paramList.get<bool>(paramName);
        paramList.remove(paramName);
      }
      bool useAverageAbsDiagVal = false;
      paramName = "chebyshev: rowsumabs use automatic diagonal tolerance";
      if (paramList.isParameter(paramName)) {
        useAverageAbsDiagVal = paramList.get<bool>(paramName);
        paramList.remove(paramName);
      }
      if (doScale) {
        const bool doReciprocal = true;
        RCP<Vector> lumpedDiagonal = Utilities::GetLumpedMatrixDiagonal(*currentA, doReciprocal, chebyReplaceTol, chebyReplaceVal, chebyReplaceSingleEntryRowWithZero, useAverageAbsDiagVal);
        const Xpetra::TpetraVector<Scalar,LocalOrdinal,GlobalOrdinal,Node>& tmpVec = dynamic_cast<const Xpetra::TpetraVector<Scalar,LocalOrdinal,GlobalOrdinal,Node>&>(*lumpedDiagonal);
        paramList.set("chebyshev: operator inv diagonal",tmpVec.getTpetra_Vector());
      }
    }
 
    return lambdaMax;
  }
 
 
 
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::SetupGeneric(Level& /* currentLevel */) {
    typedef Tpetra::RowMatrix<SC,LO,GO,NO> tRowMatrix;
    RCP<BlockedCrsMatrix> bA = rcp_dynamic_cast<BlockedCrsMatrix>(A_);
    if (!bA.is_null())
      A_ = bA->Merge();
 
    RCP<const tRowMatrix> tA = Utilities::Op2NonConstTpetraRow(A_);
 
    bool reusePreconditioner = false;
    if (this->IsSetup() == true) {
      // Reuse the constructed preconditioner
      this->GetOStream(Runtime1) << "MueLu::Ifpack2Smoother::SetupGeneric(): Setup() has already been called, assuming reuse" << std::endl;
 
      RCP<Ifpack2::Details::CanChangeMatrix<tRowMatrix> > prec = rcp_dynamic_cast<Ifpack2::Details::CanChangeMatrix<tRowMatrix> >(prec_);
      if (!prec.is_null()) {
        prec->setMatrix(tA);
        reusePreconditioner = true;
      } else {
        this->GetOStream(Warnings0) << "MueLu::Ifpack2Smoother::SetupGeneric(): reuse of this type is not available (failed cast to CanChangeMatrix), "
            "reverting to full construction" << std::endl;
      }
    }
 
    if (!reusePreconditioner) {
      prec_ = Ifpack2::Factory::create(type_, tA, overlap_);
      SetPrecParameters();
      prec_->initialize();
    }
 
    prec_->compute();
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::Apply(MultiVector& X, const MultiVector& B, bool InitialGuessIsZero) const {
    TEUCHOS_TEST_FOR_EXCEPTION(SmootherPrototype::IsSetup() == false, Exceptions::RuntimeError, "MueLu::Ifpack2Smoother::Apply(): Setup() has not been called");
 
    // Forward the InitialGuessIsZero option to Ifpack2
    // TODO:  It might be nice to switch back the internal
    //        "zero starting solution" option of the ifpack2 object prec_ to his
    //        initial value at the end but there is no way right now to get
    //        the current value of the "zero starting solution" in ifpack2.
    //        It's not really an issue, as prec_  can only be used by this method.
    Teuchos::ParameterList paramList;
    bool supportInitialGuess = false;
    const Teuchos::ParameterList params = this->GetParameterList();
 
    if (prec_->supportsZeroStartingSolution()) {
      prec_->setZeroStartingSolution(InitialGuessIsZero);
      supportInitialGuess = true;
    } else if (type_ == "SCHWARZ") {
      paramList.set("schwarz: zero starting solution", InitialGuessIsZero);
      //Because additive Schwarz has "delta" semantics, it's sufficient to
      //toggle only the zero initial guess flag, and not pass in already
      //set parameters.  If we call SetPrecParameters, the subdomain solver
      //will be destroyed.
      prec_->setParameters(paramList);
      supportInitialGuess = true;
    }
 
    //TODO JJH 30Apr2014  Calling SetPrecParameters(paramList) when the smoother
    //is Ifpack2::AdditiveSchwarz::setParameterList() will destroy the subdomain
    //(aka inner) solver.  This behavior is documented but a departure from what
    //it previously did, and what other Ifpack2 solvers currently do.  So I have
    //moved SetPrecParameters(paramList) into the if-else block above.
 
    // Apply
    if (InitialGuessIsZero || supportInitialGuess) {
      Tpetra::MultiVector<SC,LO,GO,NO>&       tpX = Utilities::MV2NonConstTpetraMV(X);
      const Tpetra::MultiVector<SC,LO,GO,NO>& tpB = Utilities::MV2TpetraMV(B);
      prec_->apply(tpB, tpX);
    } else {
      typedef Teuchos::ScalarTraits<Scalar> TST;
 
      RCP<MultiVector> Residual;
      {
        std::string prefix = this->ShortClassName() + ": Apply: ";
        RCP<TimeMonitor> tM = rcp(new TimeMonitor(*this, prefix + "residual calculation", Timings0));
        Residual = Utilities::Residual(*A_, X, B);
      }
 
      RCP<MultiVector> Correction = MultiVectorFactory::Build(A_->getDomainMap(), X.getNumVectors());
 
      Tpetra::MultiVector<SC,LO,GO,NO>&       tpX = Utilities::MV2NonConstTpetraMV(*Correction);
      const Tpetra::MultiVector<SC,LO,GO,NO>& tpB = Utilities::MV2TpetraMV(*Residual);
 
      prec_->apply(tpB, tpX);
 
      X.update(TST::one(), *Correction, TST::one());
    }
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  RCP<MueLu::SmootherPrototype<Scalar, LocalOrdinal, GlobalOrdinal, Node> > Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::Copy() const {
    RCP<Ifpack2Smoother> smoother = rcp(new Ifpack2Smoother(*this) );
    smoother->SetParameterList(this->GetParameterList());
    return smoother;
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  std::string Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::description() const {
    std::ostringstream out;
    if (SmootherPrototype::IsSetup()) {
      out << prec_->description();
    } else {
      out << SmootherPrototype::description();
      out << "{type = " << type_ << "}";
    }
    return out.str();
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  void Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::print(Teuchos::FancyOStream &out, const VerbLevel verbLevel) const {
    MUELU_DESCRIBE;
 
    if (verbLevel & Parameters0)
      out0 << "Prec. type: " << type_ << std::endl;
 
    if (verbLevel & Parameters1) {
      out0 << "Parameter list: " << std::endl;
      Teuchos::OSTab tab2(out);
      out << this->GetParameterList();
      out0 << "Overlap: "        << overlap_ << std::endl;
    }
 
    if (verbLevel & External)
      if (prec_ != Teuchos::null) {
        Teuchos::OSTab tab2(out);
        out << *prec_ << std::endl;
      }
 
    if (verbLevel & Debug) {
      out0 << "IsSetup: " << Teuchos::toString(SmootherPrototype::IsSetup()) << std::endl
           << "-" << std::endl
           << "RCP<prec_>: " << prec_ << std::endl;
    }
  }
 
  template <class Scalar,class LocalOrdinal, class GlobalOrdinal, class Node>
  size_t Ifpack2Smoother<Scalar, LocalOrdinal, GlobalOrdinal, Node>::getNodeSmootherComplexity() const {
    typedef Tpetra::RowMatrix<SC,LO,GO,NO> MatrixType;
    // NOTE: Only works for a subset of Ifpack2's smoothers
    RCP<Ifpack2::Relaxation<MatrixType> > pr     = rcp_dynamic_cast<Ifpack2::Relaxation<MatrixType> >(prec_);
    if(!pr.is_null()) return pr->getNodeSmootherComplexity();
 
    RCP<Ifpack2::Chebyshev<MatrixType> > pc       = rcp_dynamic_cast<Ifpack2::Chebyshev<MatrixType> >(prec_);
    if(!pc.is_null()) return pc->getNodeSmootherComplexity();
 
    RCP<Ifpack2::BlockRelaxation<MatrixType> > pb = rcp_dynamic_cast<Ifpack2::BlockRelaxation<MatrixType> >(prec_);
    if(!pb.is_null()) return pb->getNodeSmootherComplexity();
 
    RCP<Ifpack2::ILUT<MatrixType> > pi            = rcp_dynamic_cast<Ifpack2::ILUT<MatrixType> >(prec_);
    if(!pi.is_null()) return pi->getNodeSmootherComplexity();
 
    RCP<Ifpack2::RILUK<MatrixType> > pk            = rcp_dynamic_cast<Ifpack2::RILUK<MatrixType> >(prec_);
    if(!pk.is_null()) return pk->getNodeSmootherComplexity();
 
 
    return Teuchos::OrdinalTraits<size_t>::invalid();
  }
 
 
} // namespace MueLu
 
#endif // HAVE_MUELU_IFPACK2
#endif // MUELU_IFPACK2SMOOTHER_DEF_HPP