Template Class SingleBoundTrackParameters¶
Defined in File SingleBoundTrackParameters.hpp
Inheritance Relationships¶
Derived Type¶
public Acts::SingleCurvilinearTrackParameters< charge_t >
(Template Class SingleCurvilinearTrackParameters)
Class Documentation¶
-
template<class
charge_t
>
classActs
::
SingleBoundTrackParameters
¶ Track parameters bound to a reference surface for a single track.
This is intended as a user-facing data class that adds additional accessors and charge/momentum interpretation on top of the pure parameters vector. All parameters and their corresponding covariance matrix are stored in bound parametrization. The specific definition of the local spatial parameters is defined by the associated surface.
- Template Parameters
charge_t
: Helper type to interpret the particle charge/momentum
- Note
This class holds shared ownership on its reference surface.
Subclassed by Acts::SingleCurvilinearTrackParameters< charge_t >
Public Types
-
using
CovarianceMatrix
= BoundSymMatrix¶
-
using
ParametersVector
= BoundVector¶
-
using
Scalar
= ActsScalar¶
Public Functions
Construct from a parameters vector on the surface and particle charge.
In principle, only the charge magnitude is needed her to allow unambigous extraction of the absolute momentum. The particle charge is required as an input here to be consistent with the other constructors below that that also take the charge as an input. The charge sign is only used in debug builds to check for consistency with the q/p parameter.
- Parameters
surface
: Reference surface the parameters are defined onparams
: Bound parameters vectorq
: Particle chargecov
: Bound parameters covariance matrix
Construct from a parameters vector on the surface.
This constructor is only available if there are no potential charge ambiguities, i.e. the charge type is default-constructible.
- Parameters
surface
: Reference surface the parameters are defined onparams
: Bound parameters vectorcov
: Bound parameters covariance matrix
-
SingleBoundTrackParameters
() = delete¶ Parameters are not default constructible due to the charge type.
-
SingleBoundTrackParameters
(const SingleBoundTrackParameters&) = default¶
-
SingleBoundTrackParameters
(SingleBoundTrackParameters&&) = default¶
-
~SingleBoundTrackParameters
() = default¶
-
const std::optional<CovarianceMatrix> &
covariance
() const¶ Optional covariance matrix.
-
Vector4
fourPosition
(const GeometryContext &geoCtx) const¶ Space-time position four-vector.
This uses the associated surface to transform the local position on the surface to globalcoordinates. This requires a geometry context to select the appropriate transformation and might be a computationally expensive operation.
- Parameters
[in] geoCtx
: Geometry context for the local-to-global transformation
-
template<BoundIndices
kIndex
>
Scalarget
() const¶ Access a single parameter value indentified by its index.
- Template Parameters
kIndex
: Track parameter index
-
SingleBoundTrackParameters &
operator=
(const SingleBoundTrackParameters&) = default¶
-
SingleBoundTrackParameters &
operator=
(SingleBoundTrackParameters&&) = default¶
-
const ParametersVector &
parameters
() const¶ Parameters vector.
-
Vector3
position
(const GeometryContext &geoCtx) const¶ Spatial position three-vector.
This uses the associated surface to transform the local position on the surface to globalcoordinates. This requires a geometry context to select the appropriate transformation and might be a computationally expensive operation.
- Parameters
[in] geoCtx
: Geometry context for the local-to-global transformation
-
RotationMatrix3
referenceFrame
(const GeometryContext &geoCtx) const¶ Reference frame in which the local error is defined.
For planar surfaces, this is the transformation local-to-global rotation matrix. For non-planar surfaces, it is the local-to-global rotation matrix of the tangential plane at the track position.
- Parameters
[in] geoCtx
: Geometry context for the local-to-global transformation
Public Static Functions
Factory to construct from four-position, direction, absolute momentum, and charge.
- Note
The returned result indicates whether the free parameters could successfully be converted to on-surface parameters.
- Parameters
surface
: Reference surface the parameters are defined ongeoCtx
: Geometry context for the local-to-global transformationpos4
: Track position/time four-vectordir
: Track direction three-vector; normalization is ignored.p
: Absolute momentumq
: Particle chargecov
: Bound parameters covariance matrix
Factory to construct from four-position, direction, and charge-over-momentum.
- Note
This factory is only available if there are no potential charge ambiguities, i.e. the charge type is default-constructible. The position must be located on the surface.
- Note
The returned result indicates whether the free parameters could successfully be converted to on-surface parameters.
- Parameters
surface
: Reference surface the parameters are defined ongeoCtx
: Geometry context for the local-to-global transformationpos4
: Track position/time four-vectordir
: Track direction three-vector; normalization is ignored.qOverP
: Charge-over-momentum-like parametercov
: Bound parameters covariance matrix