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DirectedGraphToMutableDirectedGraph

vtk-examples/Cxx/Graphs/DirectedGraphToMutableDirectedGraph

Question

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Code

DirectedGraphToMutableDirectedGraph.cxx

#include <vtkDirectedGraph.h>
#include <vtkMutableDirectedGraph.h>
#include <vtkNew.h>
#include <vtkPoints.h>

int main(int, char*[])
{

  // create a graph
  vtkNew<vtkMutableDirectedGraph> mdg;

  // add 4 vertices to the graph
  vtkIdType v1 = mdg->AddVertex();
  vtkIdType v2 = mdg->AddVertex();
  vtkIdType v3 = mdg->AddVertex();
  vtkIdType v4 = mdg->AddVertex();

  // add 3 edges to the graph
  mdg->AddEdge(v1, v2);
  mdg->AddEdge(v1, v3);
  mdg->AddEdge(v1, v4);

  // create 4 points - one for each vertex
  vtkNew<vtkPoints> points;
  points->InsertNextPoint(0.0, 0.0, 0.0);
  points->InsertNextPoint(1.0, 0.0, 0.0);
  points->InsertNextPoint(0.0, 1.0, 0.0);
  points->InsertNextPoint(0.0, 0.0, 2.0);

  // add the coordinates of the points to the graph
  mdg->SetPoints(points);

  std::cout << "MDG: " << std::endl;
  std::cout << "Type: " << mdg->GetClassName() << std::endl;
  std::cout << "Vertices: " << mdg->GetNumberOfVertices() << std::endl;
  std::cout << "Edges: " << mdg->GetNumberOfEdges() << std::endl;

  vtkNew<vtkDirectedGraph> dg;
  if (!dg->CheckedShallowCopy(mdg))
  {
    std::cerr << "Could not convert graph to tree!" << std::endl;
    return EXIT_FAILURE;
  }

  std::cout << "DG: " << std::endl;
  std::cout << "Type: " << dg->GetClassName() << std::endl;
  std::cout << "Vertices: " << dg->GetNumberOfVertices() << std::endl;
  std::cout << "Edges: " << dg->GetNumberOfEdges() << std::endl;

  vtkNew<vtkMutableDirectedGraph> mdg2;

  if (!mdg2->CheckedShallowCopy(dg))
  {
    std::cerr << "Could not convert graph to tree!" << std::endl;
    return EXIT_FAILURE;
  }

  std::cout << "MDG2: " << std::endl;
  std::cout << "Type: " << mdg2->GetClassName() << std::endl;
  std::cout << "Vertices: " << mdg2->GetNumberOfVertices() << std::endl;
  std::cout << "Edges: " << mdg2->GetNumberOfEdges() << std::endl;

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(DirectedGraphToMutableDirectedGraph)

find_package(VTK COMPONENTS 
  vtkCommonCore
  vtkCommonDataModel
  QUIET
)

if (NOT VTK_FOUND)
  message("Skipping DirectedGraphToMutableDirectedGraph: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(DirectedGraphToMutableDirectedGraph MACOSX_BUNDLE DirectedGraphToMutableDirectedGraph.cxx )
  target_link_libraries(DirectedGraphToMutableDirectedGraph PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(DirectedGraphToMutableDirectedGraph MACOSX_BUNDLE DirectedGraphToMutableDirectedGraph.cxx )
  target_link_libraries(DirectedGraphToMutableDirectedGraph PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS DirectedGraphToMutableDirectedGraph
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build DirectedGraphToMutableDirectedGraph

Click here to download DirectedGraphToMutableDirectedGraph and its CMakeLists.txt file. Once the tarball DirectedGraphToMutableDirectedGraph.tar has been downloaded and extracted,

cd DirectedGraphToMutableDirectedGraph/build

If VTK is installed:

cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

Build the project:

make

and run it:

./DirectedGraphToMutableDirectedGraph

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.