Trk::MultiComponentStateCombiner Namespace Reference

Functions
std::unique_ptr< Trk::TrackParameters >	combineToSingle (const MultiComponentState &, const bool useMode=false)
	@bried Calculate combined state of many components
void	combineParametersWithWeight (AmgVector(5) &firstParameters, double &firstWeight, const AmgVector(5) &secondParameters, const double secondWeight)
	Combine parameters based on their relevant weigths.
void	combineCovWithWeight (const AmgVector(5) &firstParameters, AmgSymMatrix(5) &firstMeasuredCov, const double firstWeight, const AmgVector(5) &secondParameters, const AmgSymMatrix(5) &secondMeasuredCov, const double secondWeight)
	Combine cov matrices based on their relevant weights.

Function Documentation

combineCovWithWeight()

ATH_FLATTEN void Trk::MultiComponentStateCombiner::combineCovWithWeight	(	const AmgVector(5) &	firstParameters,
		AmgSymMatrix(5) &	firstMeasuredCov,
		const double	firstWeight,
		const AmgVector(5) &	secondParameters,
		const AmgSymMatrix(5) &	secondMeasuredCov,
		const double	secondWeight )

Combine cov matrices based on their relevant weights.

Definition at line 227 of file MultiComponentStateCombiner.cxx.

{
  double const invTotalWeight = 1.0/(firstWeight + secondWeight);
  AmgVector(5) parameterDifference = firstParameters - secondParameters;
  parameterDifference[2] = CxxUtils::wrapToPi(parameterDifference[2]);
  parameterDifference *= invTotalWeight;
  firstMeasuredCov = (firstWeight * firstMeasuredCov + secondWeight * secondMeasuredCov) * invTotalWeight;
  firstMeasuredCov += firstWeight * secondWeight * parameterDifference * parameterDifference.transpose();
}

combineParametersWithWeight()

ATH_FLATTEN void Trk::MultiComponentStateCombiner::combineParametersWithWeight	(	AmgVector(5) &	firstParameters,
		double &	firstWeight,
		const AmgVector(5) &	secondParameters,
		const double	secondWeight )

Combine parameters based on their relevant weigths.

Definition at line 201 of file MultiComponentStateCombiner.cxx.

{
  double const totalWeight = firstWeight + secondWeight;
  double const invTotalWeight = 1.0/totalWeight;
  double const deltaPhi = firstParameters[2] - secondParameters[2];
  if (deltaPhi > M_PI) {
    firstParameters[2] -= 2 * M_PI;
  } else if (deltaPhi < -M_PI) {
    firstParameters[2] += 2 * M_PI;
  }
  firstParameters =
      (firstWeight * firstParameters + secondWeight * secondParameters) *
      invTotalWeight;
  // Ensure that phi is between -pi and pi
  firstParameters[2] = CxxUtils::wrapToPi(firstParameters[2]);
  firstWeight = totalWeight;
}

combineToSingle()

std::unique_ptr< Trk::TrackParameters > Trk::MultiComponentStateCombiner::combineToSingle	(	const MultiComponentState &	uncombinedState,
		const bool	useMode = false )

@bried Calculate combined state of many components

Definition at line 190 of file MultiComponentStateCombiner.cxx.

                                                                   {
  Trk::ComponentParameters combinedComponent = combineToSingleImpl(uncombinedState, useMode);
  return std::move(combinedComponent.params);
}