Belle II Software development
HitGapSegmentRelationVarSet.cc
1/**************************************************************************
2 * basf2 (Belle II Analysis Software Framework) *
3 * Author: The Belle II Collaboration *
4 * *
5 * See git log for contributors and copyright holders. *
6 * This file is licensed under LGPL-3.0, see LICENSE.md. *
7 **************************************************************************/
8#include <tracking/trackFindingCDC/filters/segmentRelation/HitGapSegmentRelationVarSet.h>
9
10#include <tracking/trackFindingCDC/eventdata/segments/CDCSegment2D.h>
11
12#include <tracking/trackFindingCDC/numerics/Angle.h>
13
14using namespace Belle2;
15using namespace TrackFindingCDC;
16
18{
19 if (not ptrSegmentRelation) return false;
20
21 const Relation<const CDCSegment2D>& segmentPair = *ptrSegmentRelation;
22
23 const CDCSegment2D* ptrFromSegment = segmentPair.getFrom();
24 const CDCSegment2D* ptrToSegment = segmentPair.getTo();
25
26 const CDCSegment2D& fromSegment = *ptrFromSegment;
27 const CDCSegment2D& toSegment = *ptrToSegment;
28
29 const CDCRecoHit2D& fromFirstHit = fromSegment.front();
30 const CDCRecoHit2D& fromLastHit = fromSegment.back();
31
32 const CDCRecoHit2D& toFirstHit = toSegment.front();
33 const CDCRecoHit2D& toLastHit = toSegment.back();
34
35 const Vector2D fromLastHitPos = fromLastHit.getRecoPos2D();
36 const Vector2D fromFirstHitPos = fromFirstHit.getRecoPos2D();
37
38 const Vector2D toFirstHitPos = toFirstHit.getRecoPos2D();
39 const Vector2D toLastHitPos = toLastHit.getRecoPos2D();
40
41 const Vector2D hitPosGap = toFirstHitPos - fromLastHitPos;
42 const Vector2D longHitPosGap = toLastHitPos - fromFirstHitPos;
43
44 const double hitDistance = hitPosGap.norm();
45 const double longHitDistance = longHitPosGap.norm();
46
47 const Vector2D fromLastHitMom = fromLastHit.getFlightDirection2D();
48 const Vector2D toFirstHitMom = toFirstHit.getFlightDirection2D();
49
50 finitevar<named("delta_hit_pos_phi")>() = fromLastHitPos.angleWith(toFirstHitPos);
51 finitevar<named("delta_hit_mom_phi")>() = fromLastHitMom.angleWith(toFirstHitMom);
52
53 double fromLastHitAlpha = fromLastHit.getAlpha();
54 double toFirstHitAlpha = toFirstHit.getAlpha();
55 finitevar<named("delta_hit_alpha")>() = AngleUtil::normalised(toFirstHitAlpha - fromLastHitAlpha);
56
57 finitevar<named("hit_distance")>() = hitDistance;
58 finitevar<named("hit_long_distance")>() = longHitDistance;
59
60 finitevar<named("delta_hit_distance")>() = longHitDistance - hitDistance;
61
62 finitevar<named("from_hit_forward")>() = hitPosGap.dot(fromLastHitMom);
63 finitevar<named("to_hit_forward")>() = hitPosGap.dot(toFirstHitMom);
64 finitevar<named("hit_forward")>() = hitPosGap.dot(Vector2D::average(fromLastHitMom, toFirstHitMom));
65
66 const Vector2D fromStretch = fromLastHitPos - fromFirstHitPos;
67 const Vector2D toStretch = toLastHitPos - toFirstHitPos;
68
69 const double fromLength = fromStretch.norm();
70 const double toLength = toStretch.norm();
71
72 const Vector2D firstPosGap = toFirstHitPos - fromFirstHitPos;
73 const Vector2D lastPosGap = toLastHitPos - fromLastHitPos;
74
75 const double firstOffset = firstPosGap.norm();
76 const double lastOffset = lastPosGap.norm();
77
78 finitevar<named("hit_ptolemy")>() =
79 firstOffset * lastOffset - longHitDistance * hitDistance - fromLength * toLength;
80
81 return true;
82}
Class representing a two dimensional reconstructed hit in the central drift chamber.
double getAlpha() const
Getter for the direction of flight relative to the position.
Vector2D getFlightDirection2D() const
Getter for the direction of flight.
Vector2D getRecoPos2D() const
Getter for the position in the reference plane.
A reconstructed sequence of two dimensional hits in one super layer.
bool extract(const Relation< const CDCSegment2D > *ptrSegmentRelation) override
Generate and assign the contained variables.
Type for two related objects.
Definition Relation.h:21
From * getFrom() const
Getter for the pointer to the from side object.
Definition Relation.h:59
To * getTo() const
Getter for the pointer to the to side object.
Definition Relation.h:65
static constexpr int named(const char *name)
Definition VarSet.h:78
A two dimensional vector which is equipped with functions for correct handling of orientation relate...
Definition Vector2D.h:32
double dot(const Vector2D &rhs) const
Calculates the two dimensional dot product.
Definition Vector2D.h:158
static Vector2D average(const Vector2D &one, const Vector2D &two)
Constructs the average of two vectors.
Definition Vector2D.h:84
double angleWith(const Vector2D &rhs) const
The angle between this and rhs.
Definition Vector2D.h:197
double norm() const
Calculates the length of the vector.
Definition Vector2D.h:175
Abstract base class for different kinds of events.
static double normalised(const double angle)
Normalise an angle to lie in the range from [-pi, pi].
Definition Angle.h:33