#include <TrackParamsEstimationTool.h>

Inheritance diagram for ActsTrk::TrackParamsEstimationTool:

Collaboration diagram for ActsTrk::TrackParamsEstimationTool:

Public Member Functions
	TrackParamsEstimationTool (const std::string &type, const std::string &name, const IInterface *parent)

virtual	~TrackParamsEstimationTool ()=default

virtual StatusCode	initialize () override

virtual std::optional< Acts::BoundTrackParameters >	estimateTrackParameters (const ActsTrk::Seed &seed, bool useTopSp, const Acts::GeometryContext &geoContext, const Acts::MagneticFieldContext &magFieldContext, std::function< const Acts::Surface &(const ActsTrk::Seed &seed, bool useTopSp)> retrieveSurface) const override

virtual std::optional< Acts::BoundTrackParameters >	estimateTrackParameters (const ActsTrk::Seed &seed, bool useTopSp, const Acts::GeometryContext &geoContext, const Acts::MagneticFieldContext &magFieldContext, const Acts::Surface &surface, const Acts::Vector3 &bField) const override

SpacePointIndicesFun_t	spacePointIndicesFun () const override

Private Types
using	Stepper = Acts::SympyStepper

using	Navigator = Acts::VoidNavigator

using	Extrapolator = Acts::Propagator< Stepper >

Private Member Functions
const Acts::Logger &	logger () const
	Private access to the logger. More...

Private Attributes
Gaudi::Property< double >	m_sigmaLoc0

Gaudi::Property< double >	m_sigmaLoc1

Gaudi::Property< double >	m_sigmaPhi

Gaudi::Property< double >	m_sigmaTheta

Gaudi::Property< double >	m_sigmaQOverP

Gaudi::Property< double >	m_sigmaT0

Gaudi::Property< double >	m_initialSigmaPtRel

Gaudi::Property< std::vector< double > >	m_initialVarInflation

Gaudi::Property< int >	m_useLongSeeds

Gaudi::Property< int >	m_bFieldMode

Gaudi::Property< std::size_t >	m_firstSp

std::optional< Extrapolator >	m_extrapolator

std::unique_ptr< const Acts::Logger >	m_logger
	logging instance More...

SpacePointIndicesFun_t	m_spacePointIndicesFun {}

Detailed Description

Definition at line 19 of file TrackParamsEstimationTool.h.

Member Typedef Documentation

◆ Extrapolator

using ActsTrk::TrackParamsEstimationTool::Extrapolator = Acts::Propagator<Stepper>

private

Definition at line 79 of file TrackParamsEstimationTool.h.

◆ Navigator

using ActsTrk::TrackParamsEstimationTool::Navigator = Acts::VoidNavigator

private

Definition at line 78 of file TrackParamsEstimationTool.h.

◆ Stepper

using ActsTrk::TrackParamsEstimationTool::Stepper = Acts::SympyStepper

private

Definition at line 77 of file TrackParamsEstimationTool.h.

Constructor & Destructor Documentation

◆ TrackParamsEstimationTool()

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

Definition at line 15 of file TrackParamsEstimationTool.cxx.

18 : base_class(type, name, parent)

19 {}

◆ ~TrackParamsEstimationTool()

virtual ActsTrk::TrackParamsEstimationTool::~TrackParamsEstimationTool ( )

virtualdefault

Member Function Documentation

◆ estimateTrackParameters() [1/2]

std::optional< Acts::BoundTrackParameters > ActsTrk::TrackParamsEstimationTool::estimateTrackParameters	(	const ActsTrk::Seed &	seed,
		bool	useTopSp,
		const Acts::GeometryContext &	geoContext,
		const Acts::MagneticFieldContext &	magFieldContext,
		const Acts::Surface &	surface,
		const Acts::Vector3 &	bField
	)		const

overridevirtual

Definition at line 80 of file TrackParamsEstimationTool.cxx.

   {
     // Get SPs
     const auto& sp_collection = seed.sp();
     const std::size_t nSp = sp_collection.size();
     if (nSp < 3) return std::nullopt;
  
     // Function to extract the values from sp_collection
     auto sp_collection_extract = std::views::transform([&sp_collection, useTopSp](std::size_t i) {
       return sp_collection.at(useTopSp ? sp_collection.size() - i - 1 : i);
     });
  
     // Compute free parameters
     Acts::FreeVector freeParams = Acts::estimateTrackParamsFromSeed(m_spacePointIndicesFun(nSp) | sp_collection_extract, bField);
  
     if (m_useLongSeeds == 1 && nSp > 3ul) {
       auto spacePointIndicesFun2 = [](std::size_t nSp) -> std::array<std::size_t, 3> {
         return {0, nSp / 2ul, nSp - 1};
       };
       Acts::FreeVector freeParams2 = Acts::estimateTrackParamsFromSeed(spacePointIndicesFun2(nSp) | sp_collection_extract, bField);
       ATH_MSG_DEBUG("update seed p = " << 1.0 / freeParams[Acts::eFreeQOverP] << " to " << 1.0 / freeParams2[Acts::eFreeQOverP]);
       freeParams[Acts::eFreeQOverP] = freeParams2[Acts::eFreeQOverP];
     }
  
     if (useTopSp) {
       // reverse direction so momentum vector pointing outwards
       freeParams = Acts::reflectFreeParameters(freeParams);
     }
  
     // Convert free params to curvilinear params for extrapolation
     Acts::BoundTrackParameters curvilinearParams = Acts::BoundTrackParameters::createCurvilinear(
       freeParams.segment<4>(Acts::eFreePos0),
       freeParams.segment<3>(Acts::eFreeDir0),
       freeParams[Acts::eFreeQOverP],
       std::nullopt,
       Acts::ParticleHypothesis::pion());
  
     // Extrapolate to surface
     Acts::PropagatorPlainOptions propOptions(geoContext, magFieldContext);
     propOptions.direction = Acts::Direction::fromScalarZeroAsPositive(
         surface.intersect(
           geoContext,
           freeParams.segment<3>(Acts::eFreePos0),
           freeParams.segment<3>(Acts::eFreeDir0)
         ).closest().pathLength());
     auto boundParamsResult = m_extrapolator->propagateToSurface(curvilinearParams, surface, propOptions);
     if (!boundParamsResult.ok()) {
       ATH_MSG_DEBUG("Extrapolation failed");
       return std::nullopt;
     }
  
     // Get extrapolated parameters
     Acts::BoundTrackParameters boundParams = *boundParamsResult;
  
     // Estimate covariance
     Acts::EstimateTrackParamCovarianceConfig covarianceEstimationConfig = {
       .initialSigmas = {m_sigmaLoc0, m_sigmaLoc1, m_sigmaPhi, m_sigmaTheta, m_sigmaQOverP, m_sigmaT0},
       .initialSigmaPtRel = m_initialSigmaPtRel,
       .initialVarInflation = Eigen::Map<const Acts::BoundVector>(m_initialVarInflation.value().data()),
       .noTimeVarInflation = 1.0,
     };
     boundParams.covariance() = Acts::estimateTrackParamCovariance(
       covarianceEstimationConfig,
       boundParams.parameters(),
       false);
  
     return boundParams;
   }

◆ estimateTrackParameters() [2/2]

std::optional< Acts::BoundTrackParameters > ActsTrk::TrackParamsEstimationTool::estimateTrackParameters	(	const ActsTrk::Seed &	seed,
		bool	useTopSp,
		const Acts::GeometryContext &	geoContext,
		const Acts::MagneticFieldContext &	magFieldContext,
		std::function< const Acts::Surface &(const ActsTrk::Seed &seed, bool useTopSp)>	retrieveSurface
	)		const

overridevirtual

Definition at line 46 of file TrackParamsEstimationTool.cxx.

   {
     const auto& sp_collection = seed.sp();
     if ( sp_collection.size() < 3 ) return std::nullopt;
     const xAOD::SpacePoint* bottom_sp = (useTopSp && m_bFieldMode != 2) ? sp_collection.back() : sp_collection.front();
  
     // Magnetic Field
     ATLASMagneticFieldWrapper magneticField;
     Acts::MagneticFieldProvider::Cache magFieldCache = magneticField.makeCache( magFieldContext );
     Acts::Vector3 bField = *magneticField.getField( Acts::Vector3(bottom_sp->x(), bottom_sp->y(), bottom_sp->z()),
                                                     magFieldCache );
     if (m_bFieldMode == 1) {
         bField[0] = 0.0;
         bField[1] = 0.0;
     }
  
     // Get the surface
     const Acts::Surface& surface = retrieveSurface(seed, useTopSp);
  
     return estimateTrackParameters(
                    seed,
                    useTopSp,
                    geoContext,
                    magFieldContext,
                    surface,
                    bField);
   }

◆ initialize()

StatusCode ActsTrk::TrackParamsEstimationTool::initialize ( )

overridevirtual

Definition at line 21 of file TrackParamsEstimationTool.cxx.

   {
     ATH_MSG_INFO( "Initializing " << name() << "..." );
  
     ATH_MSG_DEBUG( "Properties Summary:" );
     ATH_MSG_DEBUG( "   " << m_sigmaLoc0 );
     ATH_MSG_DEBUG( "   " << m_sigmaLoc1 );
     ATH_MSG_DEBUG( "   " << m_sigmaPhi );
     ATH_MSG_DEBUG( "   " << m_sigmaTheta );
     ATH_MSG_DEBUG( "   " << m_sigmaQOverP );
     ATH_MSG_DEBUG( "   " << m_sigmaT0 );
     ATH_MSG_DEBUG( "   " << m_initialVarInflation );
     ATH_MSG_DEBUG( "   " << m_bFieldMode );
     ATH_MSG_DEBUG( "   " << m_firstSp );
  
     m_logger = makeActsAthenaLogger(this, "Acts");
  
     m_extrapolator = Extrapolator(Stepper(std::make_shared<ATLASMagneticFieldWrapper>()), Navigator(), logger().cloneWithSuffix("Prop"));
  
     m_spacePointIndicesFun = spacePointIndicesFun();
  
     return StatusCode::SUCCESS;
   }

◆ logger()

const Acts::Logger& ActsTrk::TrackParamsEstimationTool::logger ( ) const

inlineprivate

Private access to the logger.

Definition at line 84 of file TrackParamsEstimationTool.h.

     {
       return *m_logger;
     }

◆ spacePointIndicesFun()

ITrackParamsEstimationTool::SpacePointIndicesFun_t ActsTrk::TrackParamsEstimationTool::spacePointIndicesFun ( ) const

override

Definition at line 156 of file TrackParamsEstimationTool.cxx.

                                                                                                          {
     if (m_useLongSeeds == 2) {
       return [](std::size_t nSp) -> std::array<std::size_t, 3> {
         if (nSp > 3ul)
           return {0, nSp / 2ul, nSp - 1};
         else
           return {0, 1, 2};
       };
     } else if (m_firstSp > 0ul) {
       std::size_t firstSp = m_firstSp;
       return [firstSp](std::size_t nSp) -> std::array<std::size_t, 3> {
         if (nSp > 3ul) {
           std::size_t first = std::min(firstSp, nSp - 3ul);
           return {first, first + 1, first + 2};
         } else
           return {0, 1, 2};
       };
     } else {
       return [](std::size_t) -> std::array<std::size_t, 3> {
         return {0, 1, 2};
       };
     }
   };

Member Data Documentation

◆ m_bFieldMode

Gaudi::Property<int> ActsTrk::TrackParamsEstimationTool::m_bFieldMode

private

Initial value:

{this, "bFieldMode", 0,

"B-field mode: 0=B-field at first SP in search order; 1=z-component of B-field; 2=B-field at innermost SP, regardless of search direction"}

Definition at line 72 of file TrackParamsEstimationTool.h.

◆ m_extrapolator

std::optional<Extrapolator> ActsTrk::TrackParamsEstimationTool::m_extrapolator

private

Definition at line 81 of file TrackParamsEstimationTool.h.

◆ m_firstSp

Gaudi::Property<std::size_t> ActsTrk::TrackParamsEstimationTool::m_firstSp

private

Initial value:

{this, "firstSp", 0ul,

"Index of first SP to use"}

Definition at line 74 of file TrackParamsEstimationTool.h.

◆ m_initialSigmaPtRel

Gaudi::Property< double > ActsTrk::TrackParamsEstimationTool::m_initialSigmaPtRel

private

Initial value:

{this, "initialSigmaPtRel", 0.1,

"Initial relative pT resolution"}

Definition at line 66 of file TrackParamsEstimationTool.h.

◆ m_initialVarInflation

Gaudi::Property< std::vector<double> > ActsTrk::TrackParamsEstimationTool::m_initialVarInflation

private

Initial value:

{this, "initialVarInflation", {1., 1., 1., 1., 1., 1.},

"Inflate tracks"}

Definition at line 68 of file TrackParamsEstimationTool.h.

◆ m_logger

std::unique_ptr<const Acts::Logger> ActsTrk::TrackParamsEstimationTool::m_logger

private

logging instance

Definition at line 90 of file TrackParamsEstimationTool.h.

◆ m_sigmaLoc0

Gaudi::Property< double > ActsTrk::TrackParamsEstimationTool::m_sigmaLoc0

private

Initial value:

{this, "sigmaLoc0", 1 * Acts::UnitConstants::mm,

"Constant term of the loc0 resolution"}

Definition at line 54 of file TrackParamsEstimationTool.h.

◆ m_sigmaLoc1

Gaudi::Property< double > ActsTrk::TrackParamsEstimationTool::m_sigmaLoc1

private

Initial value:

{this, "sigmaLoc1", 1 * Acts::UnitConstants::mm,

"Constant term of the loc1 resolution"}

Definition at line 56 of file TrackParamsEstimationTool.h.

◆ m_sigmaPhi

Gaudi::Property< double > ActsTrk::TrackParamsEstimationTool::m_sigmaPhi

private

Initial value:

{this, "sigmaPhi", 0.1 * Acts::UnitConstants::degree,

"Phi angular resolution"}

Definition at line 58 of file TrackParamsEstimationTool.h.

◆ m_sigmaQOverP

Gaudi::Property< double > ActsTrk::TrackParamsEstimationTool::m_sigmaQOverP

private

Initial value:

{this, "sigmaQOverP", 0.1 * Acts::UnitConstants::e / Acts::UnitConstants::GeV,

"q/p resolution"}

Definition at line 62 of file TrackParamsEstimationTool.h.

◆ m_sigmaT0

Gaudi::Property< double > ActsTrk::TrackParamsEstimationTool::m_sigmaT0

private

Initial value:

{this, "sigmaT0", 1 * Acts::UnitConstants::ns,

"Time resolution"}

Definition at line 64 of file TrackParamsEstimationTool.h.

◆ m_sigmaTheta

Gaudi::Property< double > ActsTrk::TrackParamsEstimationTool::m_sigmaTheta

private

Initial value:

{this, "sigmaTheta", 0.1 * Acts::UnitConstants::degree,

"Theta angular resolution"}

Definition at line 60 of file TrackParamsEstimationTool.h.

◆ m_spacePointIndicesFun

SpacePointIndicesFun_t ActsTrk::TrackParamsEstimationTool::m_spacePointIndicesFun {}

private

Definition at line 92 of file TrackParamsEstimationTool.h.

◆ m_useLongSeeds

Gaudi::Property< int > ActsTrk::TrackParamsEstimationTool::m_useLongSeeds

private

Initial value:

{this, "useLongSeeds", 2,

"0=use 1st 3 SPs, 1=use first,middle,last SPs to improve pT measurement, 2=use for all parameters"}

Definition at line 70 of file TrackParamsEstimationTool.h.

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

Public Member Functions

Private Types

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ Extrapolator

◆ Navigator

◆ Stepper

Constructor & Destructor Documentation

◆ TrackParamsEstimationTool()

◆ ~TrackParamsEstimationTool()

Member Function Documentation

◆ estimateTrackParameters() [1/2]

◆ estimateTrackParameters() [2/2]

◆ initialize()

◆ logger()

◆ spacePointIndicesFun()

Member Data Documentation

◆ m_bFieldMode

◆ m_extrapolator

◆ m_firstSp

◆ m_initialSigmaPtRel

◆ m_initialVarInflation

◆ m_logger

◆ m_sigmaLoc0

◆ m_sigmaLoc1

◆ m_sigmaPhi

◆ m_sigmaQOverP

◆ m_sigmaT0

◆ m_sigmaTheta

◆ m_spacePointIndicesFun

◆ m_useLongSeeds