NodeFamilyDefiner.h

/**************************************************************************
 * basf2 (Belle II Analysis Software Framework)                           *
 * Author: The Belle II Collaboration                                     *
 *                                                                        *
 * See git log for contributors and copyright holders.                    *
 * This file is licensed under LGPL-3.0, see LICENSE.md.                  *
 **************************************************************************/
#pragma once
 
#include <framework/logging/Logger.h>
 
namespace Belle2 {

  template<class ContainerType, class NodeType, class NeighbourContainerType>
  class NodeFamilyDefiner {
  public:

    static short defineFamilies(ContainerType& aNetwork)
    {
      short currentFamily = 0;
      for (NodeType* aNode : aNetwork) {
        if (aNode->getFamily() != -1) {
          continue;
        }
 
        aNode->setFamily(currentFamily);
 
        NeighbourContainerType& innerNeighbours = aNode->getInnerNodes();
        NeighbourContainerType& outerNeighbours = aNode->getOuterNodes();
        NeighbourContainerType neighbours;
        neighbours.reserve(innerNeighbours.size() + outerNeighbours.size());
        neighbours.insert(neighbours.end(), innerNeighbours.begin(), innerNeighbours.end());
        neighbours.insert(neighbours.end(), outerNeighbours.begin(), outerNeighbours.end());
 
        while (neighbours.size() != 0) {
          neighbours = markNodes(currentFamily, neighbours);
        }
        currentFamily++;
      }
      return currentFamily;
    }
 
  private:
    static NeighbourContainerType markNodes(short family, const NeighbourContainerType& neighbours)
    {
      NeighbourContainerType newNeighbours;
      for (auto& neighbour : neighbours) {
        // If node was already touched continue;
        if (neighbour->getFamily() != -1) {
          short tmpFamily = neighbour->getFamily();
          if (tmpFamily != family) {
            B2FATAL("Node already assigned to different family: " << family << ", " << tmpFamily);
          } else {
            continue;
          }
        }
        neighbour->setFamily(family);
        NeighbourContainerType& innerNeighbours = neighbour->getInnerNodes();
        NeighbourContainerType& outerNeighbours = neighbour->getOuterNodes();
        newNeighbours.reserve(innerNeighbours.size() + outerNeighbours.size());
        newNeighbours.insert(newNeighbours.end(), innerNeighbours.begin(), innerNeighbours.end());
        newNeighbours.insert(newNeighbours.end(), outerNeighbours.begin(), outerNeighbours.end());
      }
      return newNeighbours;
    }
  };

}