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

Constructor from the initial bound track parameters.

Note

the covariance matrix is copied when needed

Template Parameters

  • charge_t: Type of the bound parameter charge

Parameters

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

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

  • [in] par: The track parameters at start

  • [in] ndir: The navigation direciton w.r.t momentum

  • [in] ssize: is the 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.

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.

FreeVector pars = FreeVector::Zero()

Internal free vector parameters.

double pathAccumulated = 0.

accummulated path length state

double previousStepSize = 0.
double q = 1.

The charge as the free vector can be 1/p or q/p.

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

adaptive step size of the runge-kutta integration

double tolerance = s_onSurfaceTolerance

The tolerance for the stepping.