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ColinearityKinematicConstraint Class Reference

#include <ColinearityKinematicConstraint.h>

Inheritance diagram for ColinearityKinematicConstraint:
MultiTrackKinematicConstraint

Public Types

enum  ConstraintDim { Phi, PhiTheta }
 

Public Member Functions

ColinearityKinematicConstraint * clone () const override
 
 ColinearityKinematicConstraint (ConstraintDim dim=Phi)
 
int numberOfEquations () const override
 
AlgebraicMatrix parametersDerivative (const std::vector< KinematicState > &states, const GlobalPoint &point) const override
 
AlgebraicMatrix positionDerivative (const std::vector< KinematicState > &states, const GlobalPoint &point) const override
 
AlgebraicVector value (const std::vector< KinematicState > &states, const GlobalPoint &point) const override
 
- Public Member Functions inherited from MultiTrackKinematicConstraint
 MultiTrackKinematicConstraint ()
 
virtual ~MultiTrackKinematicConstraint ()
 

Private Attributes

ConstraintDim dimension
 
unsigned int size
 

Detailed Description

Consstraint to force the two tracks to be colinear (parallel), in 2D (phi) or 3D (phi-theta).

Warning: Since this constraint makes only sense with two tracks, two and only two tracks should be used in the fit.

Definition at line 16 of file ColinearityKinematicConstraint.h.

Member Enumeration Documentation

◆ ConstraintDim

enum ColinearityKinematicConstraint::ConstraintDim
Enumerator
Phi 
PhiTheta 

Definition at line 18 of file ColinearityKinematicConstraint.h.

18 { Phi, PhiTheta };

Constructor & Destructor Documentation

◆ ColinearityKinematicConstraint()

ColinearityKinematicConstraint::ColinearityKinematicConstraint ( ConstraintDim  dim = Phi)

Definition at line 4 of file ColinearityKinematicConstraint.cc.

4  {
5  dimension = dim;
6  if (dimension == Phi)
7  size = 1;
8  else
9  size = 2;
10 }

References dimension, Phi, and size.

Referenced by clone().

Member Function Documentation

◆ clone()

ColinearityKinematicConstraint* ColinearityKinematicConstraint::clone ( void  ) const
inlineoverridevirtual

Implements MultiTrackKinematicConstraint.

Definition at line 50 of file ColinearityKinematicConstraint.h.

50 { return new ColinearityKinematicConstraint(*this); }

References ColinearityKinematicConstraint().

◆ numberOfEquations()

int ColinearityKinematicConstraint::numberOfEquations ( ) const
inlineoverridevirtual

Number of equations per track used for the fit

Implements MultiTrackKinematicConstraint.

Definition at line 48 of file ColinearityKinematicConstraint.h.

48 { return size; }

References size.

◆ parametersDerivative()

AlgebraicMatrix ColinearityKinematicConstraint::parametersDerivative ( const std::vector< KinematicState > &  states,
const GlobalPoint &  point 
) const
overridevirtual

Returns a matrix of derivatives of constraint equations w.r.t. particle parameters

Implements MultiTrackKinematicConstraint.

Definition at line 52 of file ColinearityKinematicConstraint.cc.

53  {
54  int n_st = states.size();
55  if (n_st < 2)
56  throw VertexException("ColinearityKinematicConstraint::<2 states passed");
57  AlgebraicMatrix res(size, n_st * 7, 0);
58 
59  double a_1 = -states[0].particleCharge() * states[0].magneticField()->inInverseGeV(states[0].globalPosition()).z();
60  double a_2 = -states[1].particleCharge() * states[1].magneticField()->inInverseGeV(states[1].globalPosition()).z();
61 
62  AlgebraicVector7 p1 = states[0].kinematicParameters().vector();
63  AlgebraicVector7 p2 = states[1].kinematicParameters().vector();
64 
65  double p1vx = p1(3) - a_1 * (point.y() - p1(1));
66  double p1vy = p1(4) + a_1 * (point.x() - p1(0));
67  double k1 = 1.0 / (p1vx * p1vx + p1vy * p1vy);
68  double pt1 = sqrt(p1(3) * p1(3) + p1(4) * p1(4));
69  double pTot1 = sqrt(p1(3) * p1(3) + p1(4) * p1(4) + p1(5) * p1(5));
70 
71  double p2vx = p2(3) - a_2 * (point.y() - p2(1));
72  double p2vy = p2(4) + a_2 * (point.x() - p2(0));
73  double k2 = 1.0 / (p2vx * p2vx + p2vy * p2vy);
74  double pt2 = sqrt(p2(3) * p2(3) + p2(4) * p2(4));
75  double pTot2 = sqrt(p2(3) * p2(3) + p2(4) * p2(4) + p2(5) * p2(5));
76 
77  // H_phi:
78 
79  //x1 and x2 derivatives: 1st and 8th elements
80  res(1, 1) = -k1 * a_1 * p1vx;
81  res(1, 8) = k2 * a_2 * p2vx;
82 
83  //y1 and y2 derivatives: 2nd and 9th elements:
84  res(1, 2) = -k1 * a_1 * p1vy;
85  res(1, 9) = k2 * a_2 * p2vy;
86 
87  //z1 and z2 components: 3d and 10th elmnets stay 0:
88  res(1, 3) = 0.;
89  res(1, 10) = 0.;
90 
91  //px1 and px2 components: 4th and 11th elements:
92  res(1, 4) = -k1 * p1vy;
93  res(1, 11) = k2 * p2vy;
94 
95  //py1 and py2 components: 5th and 12 elements:
96  res(1, 5) = k1 * p1vx;
97  res(1, 12) = -k2 * p2vx;
98 
99  //pz1 and pz2 components: 6th and 13 elements:
100  res(1, 6) = 0.;
101  res(1, 13) = 0.;
102  //mass components: 7th and 14th elements:
103  res(1, 7) = 0.;
104  res(1, 14) = 0.;
105 
106  if (dimension == PhiTheta) {
107  // H_theta:
108  //x1 and x2 derivatives: 1st and 8th elements
109  res(2, 1) = 0.;
110  res(2, 8) = 0.;
111 
112  //y1 and y2 derivatives: 2nd and 9th elements:
113  res(2, 2) = 0.;
114  res(2, 9) = 0.;
115 
116  //z1 and z2 components: 3d and 10th elmnets stay 0:
117  res(2, 3) = 0.;
118  res(2, 10) = 0.;
119 
120  res(2, 4) = p1(5) * p1(3) / (pTot1 * pTot1 * pt1);
121  res(2, 11) = -p2(5) * p2(3) / (pTot2 * pTot2 * pt2);
122 
123  //py1 and py2 components: 5th and 12 elements:
124  res(2, 5) = p1(5) * p1(4) / (pTot1 * pTot1 * pt1);
125  res(2, 12) = -p2(5) * p2(4) / (pTot2 * pTot2 * pt2);
126 
127  //pz1 and pz2 components: 6th and 13 elements:
128  res(2, 6) = -pt1 / (pTot1 * pTot1);
129  res(2, 13) = pt2 / (pTot2 * pTot2);
130  //mass components: 7th and 14th elements:
131  res(2, 7) = 0.;
132  res(2, 14) = 0.;
133  }
134 
135  return res;
136 }

References dimension, p1, p2, PhiTheta, point, HLT_FULL_cff::pt1, HLT_FULL_cff::pt2, size, and mathSSE::sqrt().

◆ positionDerivative()

AlgebraicMatrix ColinearityKinematicConstraint::positionDerivative ( const std::vector< KinematicState > &  states,
const GlobalPoint &  point 
) const
overridevirtual

Returns a matrix of derivatives of constraint equations w.r.t. vertex position

Implements MultiTrackKinematicConstraint.

Definition at line 138 of file ColinearityKinematicConstraint.cc.

139  {
140  AlgebraicMatrix res(size, 3, 0);
141  if (states.size() < 2)
142  throw VertexException("ColinearityKinematicConstraint::<2 states passed");
143 
144  double a_1 = -states[0].particleCharge() * states[0].magneticField()->inInverseGeV(states[0].globalPosition()).z();
145  double a_2 = -states[1].particleCharge() * states[1].magneticField()->inInverseGeV(states[1].globalPosition()).z();
146 
147  AlgebraicVector7 p1 = states[0].kinematicParameters().vector();
148  AlgebraicVector7 p2 = states[1].kinematicParameters().vector();
149 
150  double p1vx = p1(3) - a_1 * (point.y() - p1(1));
151  double p1vy = p1(4) + a_1 * (point.x() - p1(0));
152  double k1 = 1.0 / (p1vx * p1vx + p1vy * p1vy);
153  //double pt1 = sqrt(p1(3)*p1(3)+p1(4)*p1(4));
154 
155  double p2vx = p2(3) - a_2 * (point.y() - p2(1));
156  double p2vy = p2(4) + a_2 * (point.x() - p2(0));
157  double k2 = 1.0 / (p2vx * p2vx + p2vy * p2vy);
158  //double pt2 = sqrt(p2(3)*p2(3)+p2(4)*p2(4));
159 
160  // H_phi:
161 
162  // xv component
163  res(1, 1) = k1 * a_1 * p1vx - k2 * a_2 * p2vx;
164 
165  //yv component
166  res(1, 2) = k1 * a_1 * p1vy - k2 * a_2 * p2vy;
167 
168  //zv component
169  res(1, 3) = 0.;
170 
171  // H_theta: no correlation with vertex position
172  if (dimension == PhiTheta) {
173  res(2, 1) = 0.;
174  res(2, 2) = 0.;
175  res(2, 3) = 0.;
176  }
177 
178  return res;
179 }

References dimension, p1, p2, PhiTheta, point, and size.

◆ value()

AlgebraicVector ColinearityKinematicConstraint::value ( const std::vector< KinematicState > &  states,
const GlobalPoint &  point 
) const
overridevirtual

Returns a vector of values of constraint equations at the point where the input particles are defined.

Implements MultiTrackKinematicConstraint.

Definition at line 12 of file ColinearityKinematicConstraint.cc.

13  {
14  if (states.size() < 2)
15  throw VertexException("ColinearityKinematicConstraint::<2 states passed");
16  AlgebraicVector res(size, 0);
17 
18  double a_1 = -states[0].particleCharge() * states[0].magneticField()->inInverseGeV(states[0].globalPosition()).z();
19  double a_2 = -states[1].particleCharge() * states[1].magneticField()->inInverseGeV(states[1].globalPosition()).z();
20 
21  AlgebraicVector7 p1 = states[0].kinematicParameters().vector();
22  AlgebraicVector7 p2 = states[1].kinematicParameters().vector();
23 
24  double p1vx = p1(3) - a_1 * (point.y() - p1(1));
25  double p1vy = p1(4) + a_1 * (point.x() - p1(0));
26  double pt1 = sqrt(p1(3) * p1(3) + p1(4) * p1(4));
27 
28  double p2vx = p2(3) - a_2 * (point.y() - p2(1));
29  double p2vy = p2(4) + a_2 * (point.x() - p2(0));
30  double pt2 = sqrt(p2(3) * p2(3) + p2(4) * p2(4));
31 
32  // H_phi:
33  res(1) = atan2(p1vy, p1vx) - atan2(p2vy, p2vx);
34  if (res(1) > M_PI)
35  res(1) -= 2.0 * M_PI;
36  if (res(1) <= -M_PI)
37  res(1) += 2.0 * M_PI;
38  // H_theta:
39  if (dimension == PhiTheta) {
40  res(2) = atan2(pt1, p1(5)) - atan2(pt2, p2(5));
41  if (res(2) > M_PI)
42  res(2) -= 2.0 * M_PI;
43  if (res(2) <= -M_PI)
44  res(2) += 2.0 * M_PI;
45  }
46 
47  // cout << res(1) << " "<<res(2) << "\n ";// res(2)
48 
49  return res;
50 }

References dimension, M_PI, p1, p2, PhiTheta, point, HLT_FULL_cff::pt1, HLT_FULL_cff::pt2, size, and mathSSE::sqrt().

Member Data Documentation

◆ dimension

ConstraintDim ColinearityKinematicConstraint::dimension
private

Definition at line 53 of file ColinearityKinematicConstraint.h.

Referenced by ColinearityKinematicConstraint(), parametersDerivative(), positionDerivative(), and value().

◆ size

unsigned int ColinearityKinematicConstraint::size
private

Definition at line 54 of file ColinearityKinematicConstraint.h.

Referenced by ntupleDataFormat._Collection::__iter__(), ntupleDataFormat._Collection::__len__(), ColinearityKinematicConstraint(), numberOfEquations(), parametersDerivative(), positionDerivative(), cuy.FindIssue::startElement(), and value().

VertexException
Common base class.
Definition: VertexException.h:12
ColinearityKinematicConstraint::ColinearityKinematicConstraint
ColinearityKinematicConstraint(ConstraintDim dim=Phi)
Definition: ColinearityKinematicConstraint.cc:4
ColinearityKinematicConstraint::dimension
ConstraintDim dimension
Definition: ColinearityKinematicConstraint.h:53
AlgebraicVector
CLHEP::HepVector AlgebraicVector
Definition: AlgebraicObjects.h:13
mathSSE::sqrt
T sqrt(T t)
Definition: SSEVec.h:19
p2
double p2[4]
Definition: TauolaWrapper.h:90
HLT_FULL_cff.pt1
pt1
Definition: HLT_FULL_cff.py:9870
ColinearityKinematicConstraint::size
unsigned int size
Definition: ColinearityKinematicConstraint.h:54
M_PI
#define M_PI
Definition: BXVectorInputProducer.cc:49
p1
double p1[4]
Definition: TauolaWrapper.h:89
ColinearityKinematicConstraint::PhiTheta
Definition: ColinearityKinematicConstraint.h:18
AlgebraicVector7
ROOT::Math::SVector< double, 7 > AlgebraicVector7
Definition: Matrices.h:8
HLT_FULL_cff.pt2
pt2
Definition: HLT_FULL_cff.py:9872
res
Definition: Electron.h:6
AlgebraicMatrix
CLHEP::HepMatrix AlgebraicMatrix
Definition: AlgebraicObjects.h:14
ColinearityKinematicConstraint::Phi
Definition: ColinearityKinematicConstraint.h:18
point
*vegas h *****************************************************used in the default bin number in original ***version of VEGAS is ***a higher bin number might help to derive a more precise ***grade subtle point
Definition: invegas.h:5
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