Acts::EigenStepper< extension_t >::State Struct Reference

State for track parameter propagation. More...

#include <Acts/Propagator/EigenStepper.hpp>

Collaboration diagram for Acts::EigenStepper< extension_t >::State:

Public Member Functions
	State (const Options &optionsIn, MagneticFieldProvider::Cache fieldCacheIn)
	Constructor from the initial bound track parameters.

Public Attributes
Covariance	cov = Covariance::Zero()
	Covariance matrix for track parameter uncertainties.
bool	covTransport = false
	Covariance matrix (and indicator) associated with the initial error on track parameters.
FreeVector	derivative = FreeVector::Zero()
	The propagation derivative.
extension_t	extension
	Algorithmic extension.
MagneticFieldProvider::Cache	fieldCache
	This caches the current magnetic field cell and stays (and interpolates) within it as long as this is valid.
Jacobian	jacobian = Jacobian::Identity()
	The full jacobian of the transport entire transport.
BoundToFreeMatrix	jacToGlobal = BoundToFreeMatrix::Zero()
	Jacobian from local to the global frame.
FreeMatrix	jacTransport = FreeMatrix::Identity()
	Pure transport jacobian part from runge kutta integration.
std::size_t	nSteps = 0
	Total number of performed steps.
std::size_t	nStepTrials = 0
	Totoal number of attempted steps.
Options	options
	Configuration options for the Eigen stepper.
FreeVector	pars = FreeVector::Zero()
	Internal free vector parameters.
ParticleHypothesis	particleHypothesis = ParticleHypothesis::pion()
	Particle hypothesis.
double	pathAccumulated = 0.
	Accumulated path length state.
double	previousStepSize = 0.
	Last performed step (for overstep limit calculation).
StepperStatistics	statistics
	Statistics of the stepper.
struct {
Vector3   B_first {}
	Magnetic field evaluations.
Vector3   B_last {}
Vector3   B_middle {}
Vector3   k1 {}
	k_i of the RKN4 algorithm
Vector3   k2 {}
Vector3   k3 {}
Vector3   k4 {}
std::array< double, 4 >   kQoP {}
	k_i elements of the momenta
}	stepData
	Storage of magnetic field and the sub steps during a RKN4 step.
ConstrainedStep	stepSize
	Adaptive step size of the runge-kutta integration.

Detailed Description

template<typename extension_t = EigenStepperDefaultExtension>
struct Acts::EigenStepper< extension_t >::State

State for track parameter propagation.

It contains the stepping information and is provided thread local by the propagator

Constructor & Destructor Documentation

State()

template<typename extension_t = EigenStepperDefaultExtension>

Acts::EigenStepper< extension_t >::State::State	(	const Options &	optionsIn,
		MagneticFieldProvider::Cache	fieldCacheIn )

Constructor from the initial bound track parameters.

Parameters

[in]	optionsIn	is the options object for the stepper
[in]	fieldCacheIn	is the cache object for the magnetic field

Note

the covariance matrix is copied when needed

Member Data Documentation

fieldCache

template<typename extension_t = EigenStepperDefaultExtension>

MagneticFieldProvider::Cache Acts::EigenStepper< extension_t >::State::fieldCache

This caches the current magnetic field cell and stays (and interpolates) within it as long as this is valid.

See step() code for details.