Struct StraightLineStepper::State

Nested Relationships

This struct is a nested type of Class StraightLineStepper.

Struct Documentation

struct Acts::StraightLineStepper::State

State for track parameter propagation.

Public Functions

State() = delete

Delete the default constructor.

template<typename parameters_t>
State(std::reference_wrapper<const GeometryContext> gctx, std::reference_wrapper<const MagneticFieldContext>, const parameters_t &par, NavigationDirection ndir = forward, double ssize = std::numeric_limits<double>::max(), double stolerance = s_onSurfaceTolerance)

Constructor from the initial track parameters.

Template Parameters

  • parameters_t: the Type of the track parameters

Parameters

  • [in] gctx: is the context object for the geometery

  • [in] mctx: is the context object for the magnetic field

  • [in] par: The track parameters at start

  • [in] ndir: is the navigation direction

  • [in] ssize: is the (absolute) maximum step size

  • [in] stolerance: is the stepping tolerance

Public Members

Covariance cov = Covariance::Zero()
bool covTransport = false

Boolean to indiciate if you need covariance transport.

FreeVector derivative = FreeVector::Zero()

The propagation derivative.

Vector3D dir = Vector3D(1., 0., 0.)

Momentum direction (normalized)

std::reference_wrapper<const GeometryContext> geoContext
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.

NavigationDirection navDir

Navigation direction, this is needed for searching.

double p = 0.

Momentum.

double pathAccumulated = 0.

accummulated path length state

Vector3D pos = Vector3D(0., 0., 0.)

Global particle position.

double previousStepSize = 0.
double q = 0.

Save the charge: neutral as default for SL stepper.

ConstrainedStep stepSize = std::numeric_limits<double>::max()

adaptive step size of the runge-kutta integration

double t = 0.

Propagated time.

double tolerance = s_onSurfaceTolerance

The tolerance for the stepping.