ArrayLookup

VTKExamples/Cxx/Utilities/ArrayLookup

Question

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Code

ArrayLookup.cxx

#include <vtkSmartPointer.h>
#include <vtkFloatArray.h>
#include <vtkIdList.h>

int main(int, char *[])
{
  vtkSmartPointer<vtkFloatArray> distances =
    vtkSmartPointer<vtkFloatArray>::New();
  distances->SetNumberOfComponents(1);
  distances->SetName("Distances");

  distances->InsertNextValue(5);
  distances->InsertNextValue(15);
  distances->InsertNextValue(15);
  distances->InsertNextValue(25);
  distances->InsertNextValue(15);

  // Get first location
  vtkIdType result = distances->LookupValue(15);
  std::cout << "result: " << result << std::endl;

  // Get all locations
  vtkSmartPointer<vtkIdList> idList =
    vtkSmartPointer<vtkIdList>::New();
  distances->LookupValue(15, idList);
  std::cout << "found at: " << std::endl;
  for(vtkIdType i = 0; i < idList->GetNumberOfIds(); i++)
  {
    std::cout << idList->GetId(i) << " ";
  }

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(ArrayLookup)

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

Download and Build ArrayLookup

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

cd ArrayLookup/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:

./ArrayLookup

WINDOWS USERS

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