ConstructTable

VTKExamples/Cxx/Utilities/ConstructTable

Description

This example creates a 3x3 table. The columns MUST be added first - if you attempt to call AddRow type functions, they will not do anything (or produce errors) because the table still has 0 columns until you tell it otherwise. This example adds 3 empty columns to the table, then goes back and fills them in.

Warning: the table does not copy the data, so if you add the SAME column to the table each time, i.e. vtkSmartPointer vtkVariantArray> col = vtkSmartPointer vtkVariantArray>::New();

col->InsertNextValue vtkVariant(0.0)); col->InsertNextValue vtkVariant(0.0)); col->InsertNextValue vtkVariant(0.0)); table->AddColumn(Col); table->AddColumn(Col); table->AddColumn(Col);

If you modify one of the entries in the table with Table->SetValue ( r,c, vtkVariant ( counter ) ); after they have all been set to the same column, the rth entry in EVERY column will be changed.

Code

ConstructTable.cxx

#include <vtkTable.h>
#include <vtkVariant.h>
#include <vtkVariantArray.h>
#include <vtkSmartPointer.h>

int main(int, char *[])
{
  //construct an empty table
  vtkSmartPointer<vtkTable> table =
    vtkSmartPointer<vtkTable>::New();

  for ( unsigned int i = 0; i < 3; i++ )
  {
    vtkSmartPointer<vtkVariantArray> col =
      vtkSmartPointer<vtkVariantArray>::New();

    col->InsertNextValue ( vtkVariant ( 0.0 ) );
    col->InsertNextValue ( vtkVariant ( 0.0 ) );
    col->InsertNextValue ( vtkVariant ( 0.0 ) );
    table->AddColumn ( col );
  }

  //fill the table with values
  unsigned int counter = 0;
  for(vtkIdType r = 0; r < table->GetNumberOfRows(); r++ )
  {
    for(vtkIdType c = 0; c < table->GetNumberOfColumns(); c++ )
    {
      table->SetValue ( r,c, vtkVariant ( counter ) );
      counter++;
    }
  }

  //print information about the table
  std::cout << "NumRows: " << table->GetNumberOfRows() << std::endl;
  std::cout << "NumCols: " << table->GetNumberOfColumns() << std::endl;

  //display the table
  table->Dump ( 3 );

  //access elements of the table
  for(vtkIdType r = 0; r < table->GetNumberOfRows(); r++ )
  {
    for(vtkIdType c = 0; c < table->GetNumberOfColumns(); c++ )
    {
    vtkVariant v = table->GetValue( r,c);
    std::cout << "(r,c) = (" << r << "," << c << ") = " << v << std::endl;
    }
  }

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(ConstructTable)

find_package(VTK REQUIRED)
include(${VTK_USE_FILE})

add_executable(ConstructTable MACOSX_BUNDLE ConstructTable.cxx )

target_link_libraries(ConstructTable ${VTK_LIBRARIES})

Download and Build ConstructTable

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

cd ConstructTable/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:

./ConstructTable

WINDOWS USERS

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