field_utils Namespace Reference

Typedefs
using	State = G4double[G4FieldTrack::ncompSVEC]
template<unsigned int N>
using	ShortState = G4double[N]

Enumerations
enum class	Value3D { Position = 0 , Momentum = 3 , Spin = 9 }
enum class	Value1D { KineticEnergy = 6 , LabTime = 7 , ProperTime = 8 }

Functions
template<typename ArrayType >
G4double	getValue (const ArrayType &array, Value1D value)
template<typename ArrayType >
G4double	getValue2 (const ArrayType &array, Value1D value)
template<typename ArrayType >
G4double	getValue (const ArrayType &array, Value3D value)
template<typename ArrayType >
G4double	getValue2 (const ArrayType &array, Value3D value)
template<typename ArrayType >
G4ThreeVector	makeVector (const ArrayType &array, Value3D value)
G4double	absoluteError (const G4double y[], const G4double yerr[], G4double hstep)
G4double	relativeError2 (const G4double y[], const G4double yerr[], G4double hstep, G4double errorTolerance)
G4double	relativeError (const G4double y[], const G4double yerr[], G4double hstep, G4double errorTolerance)
template<typename SourceArray , typename TargetArray >
void	setValue (const SourceArray &src, Value1D value, TargetArray &trg)
template<typename SourceArray , typename TargetArray , typename ... TargetArrays>
void	setValue (const SourceArray &src, Value1D value, TargetArray &trg, TargetArrays &... trgs)
void	copy (G4double dst[], const G4double src[], size_t size=G4FieldTrack::ncompSVEC)
G4double	inverseCurvatureRadius (G4double particleCharge, G4double momentum, G4double BField)
template<typename T >
T	clamp (T value, T lo, T hi)

Typedef Documentation

ShortState

template<unsigned int N>

using field_utils::ShortState = typedef G4double[N]

Definition at line 48 of file G4FieldUtils.hh.

State

using field_utils::State = typedef G4double[G4FieldTrack::ncompSVEC]

Definition at line 45 of file G4FieldUtils.hh.

Enumeration Type Documentation

Value1D

enum class field_utils::Value1D

strong

Enumerator
KineticEnergy
LabTime
ProperTime

Definition at line 57 of file G4FieldUtils.hh.

  {
    KineticEnergy = 6,
    LabTime = 7,
    ProperTime = 8
  };

Value3D

enum class field_utils::Value3D

strong

Enumerator
Position
Momentum
Spin

Definition at line 50 of file G4FieldUtils.hh.

  {
    Position = 0,
    Momentum = 3,
    Spin = 9
  };

Function Documentation

absoluteError()

G4double field_utils::absoluteError	(	const G4double	y[],
		const G4double	yerr[],
		G4double	hstep
	)

Definition at line 38 of file G4FieldUtils.cc.

{
   const G4double momentum2 = getValue2(y, Value3D::Momentum);
   const G4double invMomentum2 = 1.0 / momentum2; 
   const G4double positionError2 = getValue2(yError, Value3D::Position);
   const G4double momentumError2 = getValue2(yError, Value3D::Momentum);
   const G4double relativeMomentumError2 = momentumError2 * invMomentum2;
 
   return std::max(std::sqrt(positionError2),
                   std::sqrt(relativeMomentumError2) * hstep);
}

clamp()

template<typename T >

T field_utils::clamp	(	T	value,
		T	lo,
		T	hi
	)

copy()

void field_utils::copy	(	G4double	dst[],
		const G4double	src[],
		size_t	size = G4FieldTrack::ncompSVEC
	)

Definition at line 98 of file G4FieldUtils.cc.

{
   std::memcpy(dst, src, sizeof(G4double) * size);
}

Referenced by G4BogackiShampine23::Stepper(), G4RK547FEq1::Stepper(), G4RK547FEq2::Stepper(), G4RK547FEq3::Stepper(), G4DormandPrince745::Stepper(), and G4TDormandPrince45< T_Equation, N >::StepWithFinalDerivate().

getValue() [1/2]

template<typename ArrayType >

G4double field_utils::getValue	(	const ArrayType &	array,
		Value1D	value
	)

Referenced by G4NystromRK4::Stepper().

getValue() [2/2]

template<typename ArrayType >

G4double field_utils::getValue	(	const ArrayType &	array,
		Value3D	value
	)

getValue2() [1/2]

template<typename ArrayType >

G4double field_utils::getValue2	(	const ArrayType &	array,
		Value1D	value
	)

Referenced by absoluteError(), relativeError2(), and G4NystromRK4::Stepper().

getValue2() [2/2]

template<typename ArrayType >

G4double field_utils::getValue2	(	const ArrayType &	array,
		Value3D	value
	)

inverseCurvatureRadius()

G4double field_utils::inverseCurvatureRadius	(	G4double	particleCharge,
		G4double	momentum,
		G4double	BField
	)

Definition at line 104 of file G4FieldUtils.cc.

{
   return -c_light * particleCharge * BField / momentum;
}

makeVector()

template<typename ArrayType >

G4ThreeVector field_utils::makeVector	(	const ArrayType &	array,
		Value3D	value
	)

Referenced by G4BogackiShampine23::DistChord(), G4DormandPrince745::DistChord(), G4RK547FEq1::DistChord(), G4RK547FEq2::DistChord(), and G4RK547FEq3::DistChord().

relativeError()

G4double field_utils::relativeError	(	const G4double	y[],
		const G4double	yerr[],
		G4double	hstep,
		G4double	errorTolerance
	)

Definition at line 90 of file G4FieldUtils.cc.

{
   return std::sqrt(relativeError2(y, yError, h, errorTolerance));
}

Referenced by G4BulirschStoer::try_step().

relativeError2()

G4double field_utils::relativeError2	(	const G4double	y[],
		const G4double	yerr[],
		G4double	hstep,
		G4double	errorTolerance
	)

Definition at line 52 of file G4FieldUtils.cc.

{
   G4double errmax_sq;
 
   G4double inv_eps_vel_sq = 1.0 / (eps_rel_max * eps_rel_max);
   G4double errvel_sq = 0.0;    // square of momentum vector difference
 
   G4double eps_pos = eps_rel_max * h; 
   G4double inv_eps_pos_sq = 1.0 / (eps_pos * eps_pos); 
 
   // Evaluate accuracy
   //
   G4double errpos_sq = getValue2(yerr, Value3D::Position);
   errpos_sq *= inv_eps_pos_sq; // Scale relative to required tolerance
 
   // Accuracy for momentum
   //
   G4double magvel_sq = getValue2(y, Value3D::Momentum);
   G4double sumerr_sq = getValue2(yerr, Value3D::Momentum); 
   if (magvel_sq > 0.0)
   {
      errvel_sq = sumerr_sq / magvel_sq; 
   }
   else
   {
      G4Exception("field_utils::relativeError","Field001",
                  JustWarning, "found case of zero momentum");
      errvel_sq = sumerr_sq; 
   }
   errvel_sq *= inv_eps_vel_sq;
   errmax_sq = std::max(errpos_sq, errvel_sq);
 
   return errmax_sq;
}

Referenced by relativeError().

setValue() [1/2]

template<typename SourceArray , typename TargetArray >

void field_utils::setValue	(	const SourceArray &	src,
		Value1D	value,
		TargetArray &	trg
	)

Referenced by G4ModifiedMidpoint::DoStep().

setValue() [2/2]

template<typename SourceArray , typename TargetArray , typename ... TargetArrays>

void field_utils::setValue	(	const SourceArray &	src,
		Value1D	value,
		TargetArray &	trg,
		TargetArrays &...	trgs
	)