Method mergeSubGraph

SRC/analysis/numberer/ParallelNumberer.cpp:364–421

int
ParallelNumberer::mergeSubGraph(Graph &theGraph, Graph &theSubGraph, ID &vertexTags, ID &vertexRefs, ID &theSubdomainMap)
{  
  // for each vertex in the SubGraph we see if a vertex exists in the Graph which has the same
  // reference tag (Reference tag in the AnalysisModel graph is the node tag) .. if so this will be 
  // the new vertex tag for SubGraph vertex in new graph, otherwise we assign it some new vertex tag,
  // create a vertex for this new vertex tag & add it to the graph

  Vertex *subVertexPtr;
  VertexIter &theSubGraphIter1 = theSubGraph.getVertices();
  int count =0;
  int numVertex = theGraph.getNumVertex();
  int numVertexSub = theSubGraph.getNumVertex();

  while ((subVertexPtr = theSubGraphIter1()) != 0) {
    int vertexTagSub = subVertexPtr->getTag();
    int vertexTagRef = subVertexPtr->getRef();
    int loc = vertexRefs.getLocation(vertexTagRef);

    int vertexTagMerged;
    if (loc < 0) {
      // if not already in, we will be creating a new vertex
      vertexTagMerged = theGraph.getFreeTag();
      vertexTags[numVertex] = vertexTagMerged;
      vertexRefs[numVertex] = vertexTagRef;
      Vertex *newVertex = new Vertex(vertexTagMerged, vertexTagRef, subVertexPtr->getWeight(), subVertexPtr->getColor());

      theGraph.addVertex(newVertex);
      numVertex++;
    } else
      vertexTagMerged = vertexTags[loc];

    // use the subgraphs ID to hold the mapping of vertex numbers between merged and original
    theSubdomainMap[count] = vertexTagSub;
    theSubdomainMap[count+numVertexSub] = vertexTagMerged;
    count++;
  }

  // for each vertex in subgraph, we add it's adjacenecy into the merged graph
  VertexIter &theSubGraphIter2 = theSubGraph.getVertices();
  while ((subVertexPtr = theSubGraphIter2()) != 0) {
    int vertexTagSub = subVertexPtr->getTag();
    int loc = theSubdomainMap.getLocation(vertexTagSub);
    int vertexTagMerged = theSubdomainMap[loc+numVertexSub];

    const ID &adjacency = subVertexPtr->getAdjacency();

    for (int i=0; i<adjacency.Size(); i++) {
      int vertexTagSubAdjacent = adjacency(i);
      int loc = theSubdomainMap.getLocation(vertexTagSubAdjacent);
      int vertexTagMergedAdjacent = theSubdomainMap[loc+numVertexSub];      
      theGraph.addEdge(vertexTagMerged, vertexTagMergedAdjacent);
    }
  }


  return 0;
}