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_decl.hpp"

#include "MueLu_LWGraph.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 LWGraph& 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).length == 1) {
      aggStat[i] = IGNORED;
      numNonAggregatedNodes--;
    }
}

}  // namespace MueLu

#endif /* MUELU_ISOLATEDNODEAGGREGATIONALGORITHM_DEF_HPP_ */