MueLu_IsolatedNodeAggregationAlgorithm_def.hpp

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/*
 * MueLu_IsolatedNodeAggregationAlgorithm_def.hpp
 *
 *  Created on: Mar 4, 2013
 *      Author: wiesner
 */

#ifndef MUELU_ISOLATEDNODEAGGREGATIONALGORITHM_DEF_HPP_
#define MUELU_ISOLATEDNODEAGGREGATIONALGORITHM_DEF_HPP_


#include <Teuchos_Comm.hpp>
#include <Teuchos_CommHelpers.hpp>

#include <Xpetra_Vector.hpp>

#include "MueLu_IsolatedNodeAggregationAlgorithm.hpp"

#include "MueLu_GraphBase.hpp"
#include "MueLu_Aggregates.hpp"
#include "MueLu_Exceptions.hpp"
#include "MueLu_Monitor.hpp"

namespace MueLu {

  template <class LocalOrdinal, class GlobalOrdinal, class Node>
  void IsolatedNodeAggregationAlgorithm<LocalOrdinal, GlobalOrdinal, Node>::BuildAggregates(const ParameterList& /* params */, const GraphBase& graph, Aggregates& /* aggregates */, std::vector<unsigned>& aggStat, LO& numNonAggregatedNodes) const {
    Monitor m(*this, "BuildAggregates");

    const LO  numRows = graph.GetNodeNumVertices();

    // Remove all isolated nodes
    for (LO i = 0; i < numRows; i++)
      if (aggStat[i] != AGGREGATED && aggStat[i] != IGNORED && graph.getNeighborVertices(i).size() == 1) {
        aggStat[i] = IGNORED;
        numNonAggregatedNodes--;
      }
  }

} // end namespace

#endif /* MUELU_ISOLATEDNODEAGGREGATIONALGORITHM_DEF_HPP_ */