HelixUtil Struct Reference

Utility struct for functions and types related to the helix parameters. More...

#include <HelixParameters.h>

Inheritance diagram for HelixUtil:

Collaboration diagram for HelixUtil:

Public Types
using	PerigeeAmbiguity = TrackFindingCDC::JacobianMatrix< 3, 5 >
	Matrix type for the ambiguity to the perigee parameters, e.g. under the stereo projection.
using	EParamaters = EHelixParameter
	Indices of the parameters.
using	ParameterVector = TrackFindingCDC::ParameterVector< c_N >
	The vector type representing the n related parameters.
using	CovarianceMatrix = TrackFindingCDC::CovarianceMatrix< c_N >
	The matrix type representing the covariance of the n related parameters.
using	PrecisionMatrix = TrackFindingCDC::PrecisionMatrix< c_N >
	The matrix type representing the precision of the n related parameters.
using	JacobianMatrix = TrackFindingCDC::JacobianMatrix< c_N >
	The matrix type used to translate covariances and precisions im auto mapping of the parameter space.

Static Public Member Functions
static HelixUtil::ParameterVector	reversalSigns ()
	Getter for the signs which have to be applied to reverse the parameters.
static PerigeeUtil::ParameterVector	getPerigeeParameters (const ParameterVector &helixPar)
	Get helix parameters related to the xy space.
static SZUtil::ParameterVector	getSZParameters (const ParameterVector &helixPar)
	Get sz parameters.
static HelixUtil::ParameterVector	stack (const PerigeeUtil::ParameterVector &perigeePar, const SZUtil::ParameterVector &szPar)
	Combine parameters from the xy space and the sz space.
static PerigeeUtil::CovarianceMatrix	getPerigeeCovariance (const CovarianceMatrix &helixCov)
	Get perigee covariance matrix related to the xy space.
static SZUtil::CovarianceMatrix	getSZCovariance (const CovarianceMatrix &helixCov)
	Get sz covariance matrix.
static HelixUtil::CovarianceMatrix	stackBlocks (const PerigeeUtil::CovarianceMatrix &perigeeCov, const SZUtil::CovarianceMatrix &szCov)
	Combine covariance matrices from the xy space and the sz space in their respective blocks.
static PerigeeAmbiguity	defaultPerigeeAmbiguity ()
	Initialse a default covariance matrix to zero.
static double	average (const HelixUtil::ParameterVector &fromPar, const HelixUtil::CovarianceMatrix &fromCov, const HelixUtil::ParameterVector &toPar, const HelixUtil::CovarianceMatrix &toCov, HelixUtil::ParameterVector &avgPar, HelixUtil::CovarianceMatrix &avgCov)
	Calculates the weighted average between two helix parameter sets with their respective covariance matrix. More...
static double	average (const PerigeeUtil::ParameterVector &fromPar, const PerigeeUtil::CovarianceMatrix &fromCov, const HelixUtil::PerigeeAmbiguity &fromAmbiguity, const HelixUtil::ParameterVector &toPar, const HelixUtil::CovarianceMatrix &toCov, HelixUtil::ParameterVector &avgPar, HelixUtil::CovarianceMatrix &avgCov)
	Calculates the weighted average between a perigee parameter sets and helix parameter sets with their respective covariance matrix under consideration of the relative ambiguity between the helix and the given perigee parameters. More...
static double	average (const PerigeeUtil::ParameterVector &fromPar, const PerigeeUtil::CovarianceMatrix &fromCov, const HelixUtil::PerigeeAmbiguity &fromAmbiguity, const PerigeeUtil::ParameterVector &toPar, const PerigeeUtil::CovarianceMatrix &toCov, const HelixUtil::PerigeeAmbiguity &toAmbiguity, const SZUtil::ParameterVector &szParameters, HelixUtil::ParameterVector &avgPar, HelixUtil::CovarianceMatrix &avgCov)
	Calculates the weighted average between two perigee parameter sets with their respective covariance matrix under consideration of their relative ambiguity to a helix near the sz parameters given as a reference. More...
static void	transport (const JacobianMatrix &jacobian, CovarianceMatrix &cov)
	Transport the covariance matrix inplace with the given jacobian matrix.
static CovarianceMatrix	transported (const JacobianMatrix &jacobian, const CovarianceMatrix &cov)
	Return a copy of the covariance matrix transported with the given jacobian matrix.
static JacobianMatrix	reversalJacobian ()
	Jacobian matrix needed in the reversal operation of the parameter vector.
static void	reverse (CovarianceMatrix &cov)
	Reverse the covariance matrix inplace.
static CovarianceMatrix	reversed (const CovarianceMatrix &cov)
	Return a copy of the reversed covariance matrix.
static CovarianceMatrix	identity ()
	Returns an identity matrix.
static CovarianceMatrix	covarianceFromPrecision (const PrecisionMatrix &prec)
	Convert the precision matrix to the corresponding covariance matrix.
static PrecisionMatrix	precisionFromCovariance (const CovarianceMatrix &cov)
	Convert the covariance matrix to the corresponding precision matrix.
static CovarianceMatrix	covarianceFromFullPrecision (const PrecisionMatrix &prec)
	Convert the precision matrix to the corresponding covariance matrix. More...
static PrecisionMatrix	precisionFromFullCovariance (const CovarianceMatrix &cov)
	Convert the covariance matrix to the corresponding precision matrix. More...
static AParameterVector	getSubParameterVector (const ParameterVector &par)
	Getter for a sub part of the covariance matrix.
static ACovarianceMatrix	getSubCovarianceMatrix (const CovarianceMatrix &cov)
	Getter for a sub part of the covariance matrix.

Static Public Attributes
static const size_t	c_N
	Number of elements.

Detailed Description

Utility struct for functions and types related to the helix parameters.

Definition at line 56 of file HelixParameters.h.

Member Function Documentation

average() [1/3]

double average ( const HelixUtil::ParameterVector &  fromPar, const HelixUtil::CovarianceMatrix &  fromCov, const HelixUtil::ParameterVector &  toPar, const HelixUtil::CovarianceMatrix &  toCov, HelixUtil::ParameterVector &  avgPar, HelixUtil::CovarianceMatrix &  avgCov  )

static

Calculates the weighted average between two helix parameter sets with their respective covariance matrix.

Returns the chi2 value of the average.

Definition at line 70 of file HelixParameters.cc.

{
  using namespace NHelixParameterIndices;
  HelixParameters refPar = (fromPar + toPar) / 2.0;
  refPar[c_Phi0] = AngleUtil::average(fromPar[c_Phi0], toPar[c_Phi0]);
 
  HelixParameters relFromPar = fromPar - refPar;
  AngleUtil::normalise(relFromPar[c_Phi0]);
 
  HelixParameters relToPar = toPar - refPar;
  AngleUtil::normalise(relToPar[c_Phi0]);
 
  HelixParameters relAvgPar;
  double chi2 =
    CovarianceMatrixUtil::average(relFromPar, fromCov, relToPar, toCov, relAvgPar, avgCov);
 
  avgPar = relAvgPar + refPar;
  AngleUtil::normalise(avgPar[c_Phi0]);
 
  return chi2;
}

average() [2/3]

double average ( const PerigeeUtil::ParameterVector &  fromPar, const PerigeeUtil::CovarianceMatrix &  fromCov, const HelixUtil::PerigeeAmbiguity &  fromAmbiguity, const HelixUtil::ParameterVector &  toPar, const HelixUtil::CovarianceMatrix &  toCov, HelixUtil::ParameterVector &  avgPar, HelixUtil::CovarianceMatrix &  avgCov  )

static

Calculates the weighted average between a perigee parameter sets and helix parameter sets with their respective covariance matrix under consideration of the relative ambiguity between the helix and the given perigee parameters.

Returns the chi2 value of the average.

Definition at line 97 of file HelixParameters.cc.

average() [3/3]

double average ( const PerigeeUtil::ParameterVector &  fromPar, const PerigeeUtil::CovarianceMatrix &  fromCov, const HelixUtil::PerigeeAmbiguity &  fromAmbiguity, const PerigeeUtil::ParameterVector &  toPar, const PerigeeUtil::CovarianceMatrix &  toCov, const HelixUtil::PerigeeAmbiguity &  toAmbiguity, const SZUtil::ParameterVector &  szParameters, HelixUtil::ParameterVector &  avgPar, HelixUtil::CovarianceMatrix &  avgCov  )

static

Calculates the weighted average between two perigee parameter sets with their respective covariance matrix under consideration of their relative ambiguity to a helix near the sz parameters given as a reference.

Returns the chi2 value of the average.

Definition at line 137 of file HelixParameters.cc.

covarianceFromFullPrecision()

auto covarianceFromFullPrecision ( const PrecisionMatrix &  prec )

staticinherited

Convert the precision matrix to the corresponding covariance matrix.

Faster version with foreknowledge that the precision is of full rank.

Definition at line 73 of file UncertainParameters.icc.h.

                        {
      return CovarianceMatrixUtil::fromFullPrecision(prec);
    }

precisionFromFullCovariance()

auto precisionFromFullCovariance ( const CovarianceMatrix &  cov )

staticinherited

Convert the covariance matrix to the corresponding precision matrix.

Faster version with foreknowledge that the precision is of full rank.

Definition at line 79 of file UncertainParameters.icc.h.

---

The documentation for this struct was generated from the following files:

• tracking/trackFindingCDC/geometry/include/HelixParameters.h
• tracking/trackFindingCDC/geometry/src/HelixParameters.cc