ActsTrk::PixelSpacePointFormationTool Class Reference

Tool to produce pixel space points. More...

#include <PixelSpacePointFormationTool.h>

Inheritance diagram for ActsTrk::PixelSpacePointFormationTool:

Collaboration diagram for ActsTrk::PixelSpacePointFormationTool:

Public Member Functions
AthAlgTool methods
	PixelSpacePointFormationTool (const std::string &type, const std::string &name, const IInterface *parent)
virtual	~PixelSpacePointFormationTool ()=default
virtual StatusCode	initialize () override
Production of space points
virtual StatusCode	producePixelSpacePoint (const xAOD::PixelCluster &cluster, xAOD::SpacePoint &sp, const InDetDD::SiDetectorElement &element) const override

Private Attributes
Id helpers
const PixelID *	m_pixelId {}
Gaudi::Property< bool >	m_useMaxVariance {this, "UseMaxVariance", false}
	Whether to use maximum variance for space point covariance If true, the covariance terms will be capped at the values specified by MaxVarianceZ and MaxVarianceR.
Gaudi::Property< float >	m_maxVarianceZ {this, "MaxVarianceZ", 0.0014f}
	Maximum variance for the z component of the space point covariance.
Gaudi::Property< float >	m_maxVarianceR {this, "MaxVarianceR", 0.015f}
	Maximum variance for the r component of the space point covariance.

Static Private Attributes
Static constant expression
Values used in calculating covariance terms
static constexpr double	s_oneOverTwelve {0.08333}

Detailed Description

Tool to produce pixel space points.

Pixel space points are obtained directly from the clusters, with needed evaluation of the space point covariance terms Space points are then recorded to storegate as ActsTrk::SpacePoint into an ActsTrk::SpacePointContainer in the PixelSpacePointFormationAlgorithm

Definition at line 28 of file PixelSpacePointFormationTool.h.

Constructor & Destructor Documentation

PixelSpacePointFormationTool()

ActsTrk::PixelSpacePointFormationTool::PixelSpacePointFormationTool	(	const std::string &	type,
		const std::string &	name,
		const IInterface *	parent )

Definition at line 14 of file PixelSpacePointFormationTool.cxx.

    : base_class(type, name, parent)
    {}

~PixelSpacePointFormationTool()

virtual ActsTrk::PixelSpacePointFormationTool::~PixelSpacePointFormationTool ( )

virtualdefault

Member Function Documentation

initialize()

StatusCode ActsTrk::PixelSpacePointFormationTool::initialize ( )

overridevirtual

Definition at line 20 of file PixelSpacePointFormationTool.cxx.

                                                        {
 
        ATH_CHECK(detStore()->retrieve(m_pixelId,"PixelID"));
 
        return StatusCode::SUCCESS;
    }

producePixelSpacePoint()

StatusCode ActsTrk::PixelSpacePointFormationTool::producePixelSpacePoint ( const xAOD::PixelCluster & cluster, xAOD::SpacePoint & sp, const InDetDD::SiDetectorElement & element ) const

overridevirtual

Definition at line 28 of file PixelSpacePointFormationTool.cxx.

    {
      // this is the width expressed in mm
      float width = cluster.widthInEta();
 
      // using width to scale the cluster covariance for space points
      float covTerm = width*width*s_oneOverTwelve;
      auto localCov = cluster.localCovariance<2>();
      if( covTerm < localCov(1, 1) )
          covTerm = localCov(1, 1);
 
      // use xz, yz, zz terms of rotation matrix to scale the covariance term
      const Amg::Transform3D &Tp = element.surface().transform();
      float cov_z = 6.f*covTerm*static_cast<float>(Tp(0, 2)*Tp(0, 2)+Tp(1, 2)*Tp(1, 2));
      float cov_r = 6.f*covTerm*static_cast<float>(Tp(2, 2)*Tp(2, 2));
 
      if (m_useMaxVariance) {
        cov_z = std::min(cov_z, m_maxVarianceZ.value());
        cov_r = std::min(cov_r, m_maxVarianceR.value());
      }
 
    sp.setSpacePoint(cluster.identifierHash(),
             cluster.globalPosition(),
             cov_r, 
             cov_z,
             std::vector< const xAOD::UncalibratedMeasurement* >({&cluster}));
    
        return StatusCode::SUCCESS;
    }

Member Data Documentation

m_maxVarianceR

Gaudi::Property<float> ActsTrk::PixelSpacePointFormationTool::m_maxVarianceR {this, "MaxVarianceR", 0.015f}

private

Maximum variance for the r component of the space point covariance.

Default value was around the minimum observed value in the pixel barrel.

Definition at line 61 of file PixelSpacePointFormationTool.h.

{this, "MaxVarianceR", 0.015f};

m_maxVarianceZ

Gaudi::Property<float> ActsTrk::PixelSpacePointFormationTool::m_maxVarianceZ {this, "MaxVarianceZ", 0.0014f}

private

Maximum variance for the z component of the space point covariance.

Default value was around the minimum observed value in the pixel barrel.

Definition at line 58 of file PixelSpacePointFormationTool.h.

{this, "MaxVarianceZ", 0.0014f};

m_pixelId

const PixelID* ActsTrk::PixelSpacePointFormationTool::m_pixelId {}

private

Definition at line 49 of file PixelSpacePointFormationTool.h.

{};

m_useMaxVariance

Gaudi::Property<bool> ActsTrk::PixelSpacePointFormationTool::m_useMaxVariance {this, "UseMaxVariance", false}

private

Whether to use maximum variance for space point covariance If true, the covariance terms will be capped at the values specified by MaxVarianceZ and MaxVarianceR.

If false, the covariance terms will be calculated based on the cluster width and the rotation of the detector element.

Definition at line 55 of file PixelSpacePointFormationTool.h.

{this, "UseMaxVariance", false};

s_oneOverTwelve

double ActsTrk::PixelSpacePointFormationTool::s_oneOverTwelve {0.08333}

staticconstexprprivate

Definition at line 65 of file PixelSpacePointFormationTool.h.

{0.08333};

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

• PixelSpacePointFormationTool.h
• PixelSpacePointFormationTool.cxx