Template Class InterpolatedBFieldMap¶

Defined in File InterpolatedBFieldMap.hpp

Nested Relationships¶

Nested Types¶

Inheritance Relationships¶

Base Type¶

public Acts::MagneticFieldProvider (Class MagneticFieldProvider)

Class Documentation¶

template<typename Mapper_t> class Acts::InterpolatedBFieldMap : public Acts::MagneticFieldProvider ¶

interpolate magnetic field value from field values on a given grid

This class implements a magnetic field service which is initialized by a field map defined by:

a list of field values on a regular grid in some n-Dimensional space,
a transformation of global 3D coordinates onto this n-Dimensional space.
a transformation of local n-Dimensional magnetic field coordinates into global (cartesian) 3D coordinates

The magnetic field value for a given global position is then determined by:

mapping the position onto the grid,
looking up the magnetic field values on the closest grid points,
doing a linear interpolation of these magnetic field values.

Public Functions

InterpolatedBFieldMap(Config config)¶

create interpolated magnetic field map

Parameters

[in] config: configuration object

Config getConfiguration() const¶

get configuration object

Return: copy of the internal configuration object

Vector3 getField(const Vector3 &position) const override¶

Vector3 getField(const Vector3 &position, MagneticFieldProvider::Cache &gcache) const override¶

Vector3 getFieldGradient(const Vector3 &position, ActsMatrix<3, 3>&) const override¶

Note: currently the derivative is not calculated

Vector3 getFieldGradient(const Vector3 &position, ActsMatrix<3, 3>&, MagneticFieldProvider::Cache&) const override¶

Note: currently the derivative is not calculated
Note: Cache is not used currently

Mapper_t getMapper() const¶

convenience method to access underlying field mapper

Return: the field mapper

double getScale() const¶

get global scaling factor for magnetic field

Return: global factor for scaling the magnetic field

bool isInside(const Vector3 &position) const¶

check whether given 3D position is inside look-up domain

Return

true if position is inside the defined BField map, otherwise false

Parameters

[in] position: global 3D position

MagneticFieldProvider::Cache makeCache(const MagneticFieldContext &mctx) const override¶

void setConfiguration(const Config &config)¶

update configuration

Parameters

[in] config: new configuration object

struct Cache¶

Public Functions

Cache(const MagneticFieldContext&)¶

Constructor with magnetic field context.

Parameters

mcfg: the magnetic field context

Public Members

std::optional<typename Mapper_t::FieldCell> fieldCell¶

bool initialized = false¶

struct Config¶

configuration object for magnetic field interpolation

Public Functions

Config(Mapper_t m)¶

Public Members

Mapper_t mapper¶

object for global coordinate transformation and interpolation

This object performs the mapping of the global 3D coordinates onto the field grid and the interpolation of the field values on close-by grid points.

double scale = 1.¶

global B-field scaling factor

Note: Negative values for scale are accepted and will invert the direction of the magnetic field.