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HelixUtil Struct Reference

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

#include <HelixParameters.h>

Inheritance diagram for HelixUtil:
UncertainParametersUtil< HelixUtil, EHelixParameter >

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.
 
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.
 
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.
 
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.
 
static PrecisionMatrix precisionFromFullCovariance (const CovarianceMatrix &cov)
 Convert the covariance matrix to the corresponding precision matrix.
 
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 Typedef Documentation

◆ CovarianceMatrix

The matrix type representing the covariance of the n related parameters.

Definition at line 36 of file UncertainParameters.h.

◆ EParamaters

using EParamaters = EHelixParameter
inherited

Indices of the parameters.

Definition at line 27 of file UncertainParameters.h.

◆ JacobianMatrix

The matrix type used to translate covariances and precisions im auto mapping of the parameter space.

Definition at line 42 of file UncertainParameters.h.

◆ ParameterVector

The vector type representing the n related parameters.

Definition at line 33 of file UncertainParameters.h.

◆ PerigeeAmbiguity

Matrix type for the ambiguity to the perigee parameters, e.g. under the stereo projection.

Definition at line 82 of file HelixParameters.h.

◆ PrecisionMatrix

The matrix type representing the precision of the n related parameters.

Definition at line 39 of file UncertainParameters.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.

76{
77 using namespace NHelixParameterIndices;
78 HelixParameters refPar = (fromPar + toPar) / 2.0;
79 refPar[c_Phi0] = AngleUtil::average(fromPar[c_Phi0], toPar[c_Phi0]);
80
81 HelixParameters relFromPar = fromPar - refPar;
82 AngleUtil::normalise(relFromPar[c_Phi0]);
83
84 HelixParameters relToPar = toPar - refPar;
85 AngleUtil::normalise(relToPar[c_Phi0]);
86
87 HelixParameters relAvgPar;
88 double chi2 =
89 CovarianceMatrixUtil::average(relFromPar, fromCov, relToPar, toCov, relAvgPar, avgCov);
90
91 avgPar = relAvgPar + refPar;
92 AngleUtil::normalise(avgPar[c_Phi0]);
93
94 return chi2;
95}
A matrix implementation to be used as an interface typ through out the track finder.
Definition: PlainMatrix.h:40
@ c_Phi0
Constant to address the azimuth angle of the direction of flight.
static void normalise(double &angle)
Normalise an angle inplace to lie in the range from [-pi, pi].
Definition: Angle.h:41
static double average(const double angle1, double angle2)
Combines two angluar values to the one that lies half way between them on the short arc.
Definition: Angle.h:27
static double average(const ParameterVector< N > &par1, const CovarianceMatrix< N > &cov1, const ParameterVector< N > &par2, const CovarianceMatrix< N > &cov2, ParameterVector< N > &par, CovarianceMatrix< N > &cov)
Averages two parameter vectors taking into account their respective covariances.

◆ 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.

104{
105 auto toAmbiguity = JacobianMatrixUtil::identity<5>();
106
107 using namespace NPerigeeParameterIndices;
108 PerigeeParameters refPar = (fromPar + toPar.head<3>()) / 2.0;
109 refPar[c_Phi0] = AngleUtil::average(fromPar[c_Phi0], toPar[c_Phi0]);
110
111 HelixParameters refHelixPar = stack(refPar, toPar.tail<2>());
112
113 PerigeeParameters relFromPar = fromPar - refPar;
114 AngleUtil::normalise(relFromPar[c_Phi0]);
115
116 HelixParameters relToPar = toPar - refHelixPar;
117 AngleUtil::normalise(relToPar[c_Phi0]);
118
119 HelixParameters relAvgPar;
120
121 // Chi2 value
122 double chi2 = CovarianceMatrixUtil::average(relFromPar,
123 fromCov,
124 fromAmbiguity,
125 relToPar,
126 toCov,
127 toAmbiguity,
128 relAvgPar,
129 avgCov);
130
131 avgPar = relAvgPar + refHelixPar;
132 AngleUtil::normalise(avgPar[c_Phi0]);
133
134 return chi2;
135}
static HelixUtil::ParameterVector stack(const PerigeeUtil::ParameterVector &perigeePar, const SZUtil::ParameterVector &szPar)
Combine parameters from the xy space and the sz space.

◆ 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.

146{
147 using namespace NPerigeeParameterIndices;
148 PerigeeParameters refPar = (fromPar + toPar) / 2.0;
149 refPar[c_Phi0] = AngleUtil::average(fromPar[c_Phi0], toPar[c_Phi0]);
150
151 HelixParameters refHelixPar = stack(refPar, szParameters);
152
153 PerigeeParameters relFromPar = fromPar - refPar;
154 AngleUtil::normalise(relFromPar[c_Phi0]);
155
156 PerigeeParameters relToPar = toPar - refPar;
157 AngleUtil::normalise(relToPar[c_Phi0]);
158
159 HelixParameters relAvgPar;
160
161 // Chi2 value
162 double chi2 = CovarianceMatrixUtil::average(relFromPar,
163 fromCov,
164 fromAmbiguity,
165 relToPar,
166 toCov,
167 toAmbiguity,
168 relAvgPar,
169 avgCov);
170
171 avgPar = relAvgPar + refHelixPar;
172 AngleUtil::normalise(avgPar[c_Phi0]);
173
174 return chi2;
175}

◆ 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.

92 {
93 return CovarianceMatrixUtil::fromFullPrecision(prec);
94 }

◆ covarianceFromPrecision()

auto covarianceFromPrecision ( const PrecisionMatrix prec)
staticinherited

Convert the precision matrix to the corresponding covariance matrix.

Definition at line 64 of file UncertainParameters.icc.h.

78 {
79 return CovarianceMatrixUtil::fromPrecision(prec);
80 }

◆ defaultPerigeeAmbiguity()

HelixUtil::PerigeeAmbiguity defaultPerigeeAmbiguity ( )
static

Initialse a default covariance matrix to zero.

Definition at line 65 of file HelixParameters.cc.

66{
68}
static PlainMatrix< T, M, N > Zero()
Construct a matrix initialized with zeros.
Definition: PlainMatrix.h:67

◆ getPerigeeCovariance()

PerigeeUtil::CovarianceMatrix getPerigeeCovariance ( const CovarianceMatrix helixCov)
static

Get perigee covariance matrix related to the xy space.

Definition at line 46 of file HelixParameters.cc.

47{
48 using namespace NHelixParameterIndices;
49 return getSubCovarianceMatrix<PerigeeUtil::CovarianceMatrix, c_Curv>(helixCov);
50}

◆ getPerigeeParameters()

PerigeeUtil::ParameterVector getPerigeeParameters ( const ParameterVector helixPar)
static

Get helix parameters related to the xy space.

Definition at line 27 of file HelixParameters.cc.

28{
29 using namespace NHelixParameterIndices;
30 return getSubParameterVector<PerigeeUtil::ParameterVector, c_Curv>(helixPar);
31}

◆ getSubCovarianceMatrix()

ACovarianceMatrix getSubCovarianceMatrix ( const CovarianceMatrix cov)
staticinherited

Getter for a sub part of the covariance matrix.

Definition at line 87 of file UncertainParameters.icc.h.

71 {
72 return CovarianceMatrixUtil::getSub<ACovarianceMatrix, I>(cov);
73 }

◆ getSubParameterVector()

AParameterVector getSubParameterVector ( const ParameterVector par)
staticinherited

Getter for a sub part of the covariance matrix.

Definition at line 83 of file UncertainParameters.icc.h.

63 {
64 return ParameterVectorUtil::getSub<AParameterVector, I>(par);
65 }

◆ getSZCovariance()

SZUtil::CovarianceMatrix getSZCovariance ( const CovarianceMatrix helixCov)
static

Get sz covariance matrix.

Definition at line 52 of file HelixParameters.cc.

53{
54 using namespace NHelixParameterIndices;
55 return getSubCovarianceMatrix<SZUtil::CovarianceMatrix, c_TanL>(helixCov);
56}

◆ getSZParameters()

SZUtil::ParameterVector getSZParameters ( const ParameterVector helixPar)
static

Get sz parameters.

Definition at line 33 of file HelixParameters.cc.

34{
35 using namespace NHelixParameterIndices;
36 return getSubParameterVector<SZUtil::ParameterVector, c_TanL>(helixPar);
37}

◆ identity()

auto identity
staticinherited

Returns an identity matrix.

Definition at line 61 of file UncertainParameters.icc.h.

55 {
56 return CovarianceMatrixUtil::identity<c_N>();
57 }

◆ precisionFromCovariance()

auto precisionFromCovariance ( const CovarianceMatrix cov)
staticinherited

Convert the covariance matrix to the corresponding precision matrix.

Definition at line 67 of file UncertainParameters.icc.h.

85 {
86 return CovarianceMatrixUtil::toPrecision(cov);
87 }

◆ 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.

99 {
100 return CovarianceMatrixUtil::fullToPrecision(cov);
101 }

◆ reversalJacobian()

auto reversalJacobian
staticinherited

Jacobian matrix needed in the reversal operation of the parameter vector.

Definition at line 52 of file UncertainParameters.icc.h.

38 {
39 return JacobianMatrixUtil::scale(T::reversalSigns());
40 }

◆ reversalSigns()

HelixUtil::ParameterVector reversalSigns ( )
static

Getter for the signs which have to be applied to reverse the parameters.

Definition at line 22 of file HelixParameters.cc.

23{
25}
static ParameterVector< N1+N2 > stack(const ParameterVector< N1 > &upperPar, const ParameterVector< N2 > &lowerPar)
Combines two parameter vectors by stacking them over each other.
static ParameterVector reversalSigns()
Getter for the signs which have to be applied to reverse the traversal direction.
static ParameterVector reversalSigns()
Getter for the signs which have to be applied to reverse the parameters.
Definition: SZParameters.h:47

◆ reverse()

void reverse ( CovarianceMatrix cov)
staticinherited

Reverse the covariance matrix inplace.

Definition at line 55 of file UncertainParameters.icc.h.

44 {
45 return transport(reversalJacobian(), cov);
46 }
static void transport(const JacobianMatrix &jacobian, CovarianceMatrix &cov)
Transport the covariance matrix inplace with the given jacobian matrix.
static JacobianMatrix reversalJacobian()
Jacobian matrix needed in the reversal operation of the parameter vector.

◆ reversed()

auto reversed ( const CovarianceMatrix cov)
staticinherited

Return a copy of the reversed covariance matrix.

Definition at line 58 of file UncertainParameters.icc.h.

50 {
51 return transported(reversalJacobian(), cov);
52 }
static CovarianceMatrix transported(const JacobianMatrix &jacobian, const CovarianceMatrix &cov)
Return a copy of the covariance matrix transported with the given jacobian matrix.

◆ stack()

HelixUtil::ParameterVector stack ( const PerigeeUtil::ParameterVector perigeePar,
const SZUtil::ParameterVector szPar 
)
static

Combine parameters from the xy space and the sz space.

Definition at line 39 of file HelixParameters.cc.

41{
42 ParameterVector result = ParameterVectorUtil::stack(perigeePar, szPar);
43 return result;
44}

◆ stackBlocks()

HelixUtil::CovarianceMatrix stackBlocks ( const PerigeeUtil::CovarianceMatrix perigeeCov,
const SZUtil::CovarianceMatrix szCov 
)
static

Combine covariance matrices from the xy space and the sz space in their respective blocks.

Definition at line 58 of file HelixParameters.cc.

60{
61 CovarianceMatrix result = CovarianceMatrixUtil::stackBlocks(perigeeCov, szCov);
62 return result;
63}
static CovarianceMatrix< N1+N2 > stackBlocks(const CovarianceMatrix< N1 > &block1, const CovarianceMatrix< N2 > &block2)
Combines two covariance matrices by putting them in two blocks on the diagonal of a larger matrix.

◆ transport()

void transport ( const JacobianMatrix jacobian,
CovarianceMatrix cov 
)
staticinherited

Transport the covariance matrix inplace with the given jacobian matrix.

Definition at line 45 of file UncertainParameters.icc.h.

26 {
27 CovarianceMatrixUtil::transport(jacobian, cov);
28 }

◆ transported()

auto transported ( const JacobianMatrix jacobian,
const CovarianceMatrix cov 
)
staticinherited

Return a copy of the covariance matrix transported with the given jacobian matrix.

Definition at line 48 of file UncertainParameters.icc.h.

33 {
34 return CovarianceMatrixUtil::transported(jacobian, cov);
35 }

Member Data Documentation

◆ c_N

const size_t c_N
staticinherited

Number of elements.

Definition at line 30 of file UncertainParameters.h.


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