Method ComputeDataProperties

Views/Infovis/vtkParallelCoordinatesRepresentation.cxx:660–735

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//------------------------------------------------------------------------------
int vtkParallelCoordinatesRepresentation::ComputeDataProperties()
{
  // if the data hasn't changed, there's no reason to recompute
  if (this->BuildTime > this->GetInput()->GetMTime())
  {
    return 1;
  }

  int numberOfInputArrays = this->InputArrayTable->GetNumberOfColumns();
  int newNumberOfAxes = 0;
  int newNumberOfSamples = 0;

  // stores the array names, if there are any
  vtkSmartPointer<vtkStringArray> newtitles = vtkSmartPointer<vtkStringArray>::New();

  for (int i = 0; i < numberOfInputArrays; i++)
  {
    vtkAbstractArray* array = this->InputArrayTable->GetColumn(i);
    int numTuples = array->GetNumberOfTuples();

    if (i > 0 && newNumberOfSamples != numTuples)
    {
      vtkErrorMacro(<< "Error: all arrays must have the same number of values!");
      return 0;
    }
    else
    {
      newNumberOfSamples = numTuples;
    }

    newNumberOfAxes++;

    if (array->GetName())
    {
      newtitles->InsertNextValue(array->GetName());
    }
  }

  if (newNumberOfAxes <= 0 || newNumberOfSamples <= 0)
  {
    return 0;
  }

  // did the number of axes change? reinitialize EVERYTHING.
  if (newNumberOfAxes != this->NumberOfAxes || newNumberOfSamples != this->NumberOfSamples)
  {
    // make sure that the old ones get removed
    for (int i = 0; i < this->NumberOfAxes; i++)
    {
      this->RemovePropOnNextRender(this->Axes[i]);
    }

    this->NumberOfAxes = newNumberOfAxes;
    this->NumberOfSamples = newNumberOfSamples;

    this->ReallocateInternals();
  }