BlineTracer/src/G4BlineEquation.cc

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0026 /// \file field/BlineTracer/src/G4BlineEquation.cc
0027 /// \brief Implementation of the G4BlineEquation class
0028 //
0029 //
0030 //
0031 //
0032 // --------------------------------------------------------------------
0033 //
0034 // G4BlineEquation implementation
0035 //
0036 // --------------------------------------------------------------------
0037 // Author: Laurent Desorgher (desorgher@phim.unibe.ch)
0038 //         Created - 2003-10-06
0039 // --------------------------------------------------------------------
0040
0041 #include "G4BlineEquation.hh"
0042
0043 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0044
0045 G4BlineEquation::G4BlineEquation(G4MagneticField* magField) : G4Mag_EqRhs(magField) {}
0046
0047 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0048
0049 void G4BlineEquation::EvaluateRhsGivenB(const G4double y[], const G4double B[3],
0050                                         G4double dydx[]) const
0051 {
0052   G4double Bmag = fDirection * std::sqrt(B[0] * B[0] + B[1] * B[1] + B[2] * B[2]);
0053   dydx[0] = B[0] / Bmag;
0054   dydx[1] = B[1] / Bmag;
0055   dydx[2] = B[2] / Bmag;
0056
0057   dydx[3] = 0. * y[0];  // y[0] is used to remove warning
0058   dydx[4] = 0.;
0059   dydx[5] = 0.;
0060 }
0061
0062 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0063
0064 void G4BlineEquation::SetBackwardDirectionOfIntegration(G4bool abool)
0065 {
0066   fBackward_direction = abool;
0067   fDirection = 1.;
0068   if (fBackward_direction) fDirection = -1.;
0069 }