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geant4/source/geometry/magneticfield/include/G4MagHelicalStepper.icc
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// G4MagHelicalStepper inline methods implementation
//
// Author: John Apostolakis (CERN), 05.11.1998
// --------------------------------------------------------------------
inline void
G4MagHelicalStepper::LinearStep( const G4double yIn[],
G4double h,
G4double yLinear[]) const
{
// Linear Step in regions of no field
G4double momentum_val = std::sqrt(yIn[3]*yIn[3]+yIn[4]*yIn[4]+yIn[5]*yIn[5]);
G4double inv_momentum = 1.0 / momentum_val;
G4double yDir[3];
for( auto i = 0; i < 3; ++i )
{
yDir[i] = inv_momentum * yIn[i+3];
yLinear[i] = yIn[i] + h * yDir[i];
yLinear[i+3] = yIn[i+3];
}
}
inline void
G4MagHelicalStepper::MagFieldEvaluate(const G4double y[],
G4ThreeVector& Bfield )
{
G4double B[3];
GetEquationOfMotion()->GetFieldValue(y, B);
Bfield = G4ThreeVector( B[0], B[1], B[2] );
}
inline G4double
G4MagHelicalStepper::GetInverseCurve(const G4double Momentum,
const G4double Bmag)
{
constexpr G4double chargeFactor = 1.0 / (CLHEP::eplus*CLHEP::c_light);
G4double inv_momentum = 1.0 / Momentum ;
G4double particleCharge = fPtrMagEqOfMot->FCof() * chargeFactor;
G4double fCoefficient = -fUnitConstant * particleCharge * inv_momentum;
return fCoefficient*Bmag;
}
inline void G4MagHelicalStepper::SetAngCurve(const G4double Ang)
{
fAngCurve=Ang;
}
inline G4double G4MagHelicalStepper::GetAngCurve() const
{
return fAngCurve;
}
inline void G4MagHelicalStepper::SetCurve(const G4double Curve)
{
frCurve=Curve;
}
inline G4double G4MagHelicalStepper::GetCurve() const
{
return frCurve;
}
inline void G4MagHelicalStepper::SetRadHelix(const G4double Rad)
{
frHelix=Rad;
}
inline G4double G4MagHelicalStepper::GetRadHelix() const
{
return frHelix;
}