Trk::GsfMeasurementUpdator Namespace Reference

Functions
MultiComponentState	update (Trk::MultiComponentState &&, const Trk::MeasurementBase &, FitQualityOnSurface &fitQoS)
	Method for updating the multi-state with a new measurement and calculate the fit qaulity at the same time.
FitQualityOnSurface	fitQuality (const MultiComponentState &, const MeasurementBase &)
	Method for determining the chi2 of the multi-component state and the number of degrees of freedom.

Function Documentation

fitQuality()

Trk::FitQualityOnSurface Trk::GsfMeasurementUpdator::fitQuality	(	const MultiComponentState &	updatedState,
		const MeasurementBase &	measurement )

Method for determining the chi2 of the multi-component state and the number of degrees of freedom.

Definition at line 846 of file GsfMeasurementUpdator.cxx.

{
  double chi2 = 0;
  Trk::FitQualityOnSurface componentFitQuality;
  for (const Trk::ComponentParameters& component: updatedState) {
    stateFitQuality(componentFitQuality,
                    *component.params.get(),
                    measurement.localParameters(),
                    measurement.localCovariance());
 
    chi2 += component.weight * componentFitQuality.chiSquared();
  }
 
  //The same measurement is included
  return { chi2, componentFitQuality.numberDoF() };
}

update()

Trk::MultiComponentState Trk::GsfMeasurementUpdator::update	(	Trk::MultiComponentState &&	stateBeforeUpdate,
		const Trk::MeasurementBase &	measurement,
		FitQualityOnSurface &	fitQoS )

Method for updating the multi-state with a new measurement and calculate the fit qaulity at the same time.

Definition at line 809 of file GsfMeasurementUpdator.cxx.

{
 
  // Check all components have associated error matrices
  bool rebuildStateWithErrors = false;
  // Perform initial check of state awaiting update. If all states have
  // associated error matricies then no need to perform the rebuild
  for (const Trk::ComponentParameters& component : stateBeforeUpdate) {
    rebuildStateWithErrors =
      rebuildStateWithErrors || invalidComponent(component.params.get());
  }
 
  if (rebuildStateWithErrors) {
    Trk::MultiComponentState stateWithInsertedErrors =
      rebuildState(std::move(stateBeforeUpdate));
    // Perform the measurement update with the modified state
    Trk::MultiComponentState updatedState = calculateFilterStep(
      std::move(stateWithInsertedErrors), measurement, fitQoS);
    if (updatedState.empty()) {
      return {};
    }
    return updatedState;
  }
 
  // Perform the measurement update
  Trk::MultiComponentState updatedState = calculateFilterStep(
    std::move(stateBeforeUpdate), measurement, fitQoS);
 
  if (updatedState.empty()) {
    return {};
  }
  return updatedState;
}