Method buildMaxflowGraph

IO/Infovis/vtkDIMACSGraphReader.cxx:200–324

============================================================================ Build a graph from a max-flow problem. These are directed. These should have TWO node descriptor lines of the format: n ID where is either an 's' or a 't', for the source and sink, respectively. Format of edge lines is: a u v cap to create an edge u->v, and cap gives the edge capacity.

//         a u v cap
//   to create an edge u->v, and cap gives the edge capacity.
int vtkDIMACSGraphReader::buildMaxflowGraph(vtkGraph* output)
{
  std::string S;
  int iEdgeU, iEdgeV, iVertexID;
  int currentEdgeId = 0;
  int numSrcs = 0;
  int numSinks = 0;

  std::string sAttribute;
  VTK_CREATE(vtkMutableDirectedGraph, builder);

  VTK_CREATE(vtkIntArray, vertexSourceArray);
  VTK_CREATE(vtkIntArray, vertexSinkArray);
  VTK_CREATE(vtkIntArray, edgeCapacityArray);

  VTK_CREATE(vtkIntArray, vertexPedigreeIds);
  VTK_CREATE(vtkIntArray, edgePedigreeIds);

  vertexSourceArray->SetName("sources");
  vertexSinkArray->SetName("sinks");
  edgeCapacityArray->SetName("capacity");

  vertexSourceArray->SetNumberOfTuples(this->numVerts);
  vertexSinkArray->SetNumberOfTuples(this->numVerts);
  edgeCapacityArray->SetNumberOfTuples(this->numEdges);

  for (int i = 0; i < this->numVerts; i++)
  {
    vertexSourceArray->SetValue(i, 0);
    vertexSinkArray->SetValue(i, 0);
  }

  for (int i = 0; i < this->numEdges; i++)
  {
    edgeCapacityArray->SetValue(i, 0);
  }

  // Set up Pedigree-IDs arrays.
  vertexPedigreeIds->SetName("vertex id");
  vertexPedigreeIds->SetNumberOfTuples(this->numVerts);
  edgePedigreeIds->SetName("edge id");
  edgePedigreeIds->SetNumberOfTuples(this->numEdges);

  // Allocate Vertices in the graph builder
  for (int i = 0; i < this->numVerts; i++)
  {
    builder->AddVertex();
    vertexPedigreeIds->SetValue(i, i + 1);
  }

  // set starting edge id number.
  int baseEdgeId = 1;

  vtksys::ifstream IFP(this->FileName);
  if (IFP.is_open())
  {
    while (vtksys::SystemTools::GetLineFromStream(IFP, S))
    {