Method RequestData

Filters/Statistics/vtkStatisticsAlgorithm.cxx:467–559

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//------------------------------------------------------------------------------
int vtkStatisticsAlgorithm::RequestData(
  vtkInformation*, vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  // Extract inputs
  vtkTable* inData = vtkTable::GetData(inputVector[INPUT_DATA], 0);
  auto* inModel = vtkStatisticalModel::GetData(inputVector[INPUT_MODEL], 0);
  vtkTable* inParameters = vtkTable::GetData(inputVector[LEARN_PARAMETERS], 0);

  // Extract outputs
  vtkTable* outData = vtkTable::GetData(outputVector, OUTPUT_DATA);
  auto* outModel = vtkStatisticalModel::GetData(outputVector, OUTPUT_MODEL);
  vtkTable* outTest = vtkTable::GetData(outputVector, OUTPUT_TEST);

  // If input data table is not null then shallow copy it to output and count ghosts
  // if they are present (so that Learn, Derive, Test, and Assess can use it to
  // adjust sample counts as needed).
  if (inData)
  {
    outData->ShallowCopy(inData);
    outData->GetRowData()->RemoveArray(vtkDataSetAttributes::GhostArrayName());

    // Only count ghosts if GhostsToSkip has 1+ bits set and we have ghost marks.
    vtkUnsignedCharArray* ghosts = inData->GetRowData()->GetGhostArray();
    if (ghosts && this->GhostsToSkip)
    {
      ::GhostsCounter counter(ghosts, this->GhostsToSkip);
      vtkSMPTools::For(0, ghosts->GetNumberOfValues(), counter);
      this->NumberOfGhosts = counter.GlobalNumberOfGhosts;
    }
    else
    {
      this->NumberOfGhosts = 0;
    }
  }

  // If there are any columns selected in the buffer which have not been
  // turned into a request by RequestSelectedColumns(), add them now.
  // There should be no effect if vtkStatisticsAlgorithmPrivate::Buffer is empty.
  // This is here to accommodate the simpler user interfaces in OverView for
  // univariate and bivariate algorithms which will not call RequestSelectedColumns()
  // on their own.
  this->RequestSelectedColumns();

  // Calculate primary statistics if requested
  if (this->LearnOption)
  {
    // First, learn primary statistics from data; otherwise, only use input model as output model
    this->Learn(inData, inParameters, outModel);

    // Second, aggregate learned models with input model if one is present
    if (inModel)
    {
      vtkDataObjectCollection* models = vtkDataObjectCollection::New();
      models->AddItem(inModel);
      models->AddItem(outModel);
      this->Aggregate(models, outModel);
      models->Delete();
    }