Geant4  10.01.p02
G4HelixSimpleRunge.cc
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27 // $Id: G4HelixSimpleRunge.cc 66356 2012-12-18 09:02:32Z gcosmo $
28 //
29 //
30 // Simple Runge:
31 // x_1 = x_0 + h * ( dx( t_0+h/2, x_0 + h/2 * dx( t_0, x_0) ) )
32 //
33 // Second order solver.
34 // Take the derivative at a position to be assumed at the middle of the
35 // Step and add it to the current position.
36 //
37 // W.Wander <wwc@mit.edu> 12/09/97
38 // -------------------------------------------------------------------------
39 
40 #include "G4HelixSimpleRunge.hh"
41 #include "G4ThreeVector.hh"
42 
43 void
45  G4ThreeVector Bfld,
46  G4double h,
47  G4double yOut[])
48 {
49  const G4int nvar = 6 ;
50  G4double yTemp[nvar]; // , yAdd[nvar];
51  G4ThreeVector Bfld_midpoint;
52 
53  AdvanceHelix( yIn, Bfld, 0.5 * h, yTemp);
54 
55  // now obtain the new field value at the new point
56  MagFieldEvaluate(yTemp, Bfld_midpoint);
57 
58  AdvanceHelix( yIn, Bfld_midpoint, h, yOut);
59 
60  // NormaliseTangentVector( yOut );
61 }
void AdvanceHelix(const G4double yIn[], G4ThreeVector Bfld, G4double h, G4double yHelix[], G4double yHelix2[]=0)
CLHEP::Hep3Vector G4ThreeVector
void MagFieldEvaluate(const G4double y[], G4ThreeVector &Bfield)
int G4int
Definition: G4Types.hh:78
void DumbStepper(const G4double y[], G4ThreeVector Bfld, G4double h, G4double yout[])
double G4double
Definition: G4Types.hh:76