RemoveIsolatedVertices

VTKEx/Cxx/Graphs/RemoveIsolatedVertices

Question

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Code

RemoveIsolatedVertices.cxx

#include <vtkSmartPointer.h>

#include <vtkMutableUndirectedGraph.h>
#include <vtkPoints.h>
#include <vtkRemoveIsolatedVertices.h>

int main(int, char *[])
{
  vtkSmartPointer<vtkMutableUndirectedGraph> g = 
      vtkSmartPointer<vtkMutableUndirectedGraph>::New();

  // Create 3 vertices
  vtkIdType v1 = g->AddVertex();
  vtkIdType v2 = g->AddVertex();
  g->AddVertex();

  g->AddEdge ( v1, v2 );

  std::cout << "Graph has "
            << g->GetNumberOfVertices()
            << " vertices and " 
            << g->GetNumberOfEdges() << " edge before." << std::endl;

  vtkSmartPointer<vtkRemoveIsolatedVertices> filter = 
    vtkSmartPointer<vtkRemoveIsolatedVertices>::New();
  filter->SetInputConnection(g->GetProducerPort());
  filter->Update();

  std::cout << "Graph has "
            << filter->GetOutput()->GetNumberOfVertices() 
            << " vertices and "
            << filter->GetOutput()->GetNumberOfEdges()
            << " edge after." << std::endl;

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(RemoveIsolatedVertices)

find_package(VTK COMPONENTS 
  vtkvtkCommonCore
  vtkvtkCommonDataModel
  vtkvtkInfovisCore QUIET)
if (NOT VTK_FOUND)
  message("Skipping RemoveIsolatedVertices: ${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(RemoveIsolatedVertices MACOSX_BUNDLE RemoveIsolatedVertices.cxx )
  target_link_libraries(RemoveIsolatedVertices PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(RemoveIsolatedVertices MACOSX_BUNDLE RemoveIsolatedVertices.cxx )
  target_link_libraries(RemoveIsolatedVertices PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS RemoveIsolatedVertices
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build RemoveIsolatedVertices

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

cd RemoveIsolatedVertices/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:

./RemoveIsolatedVertices

WINDOWS USERS

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