Geant4  10.02
G4ExplicitEuler.cc
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27 // $Id: G4ExplicitEuler.cc 66356 2012-12-18 09:02:32Z gcosmo $
28 //
29 //
30 // Explicit Euler: x_1 = x_0 + h * dx_0
31 //
32 // most simple approach for solving linear differential equations.
33 // Take the current derivative and add it to the current position.
34 //
35 // W.Wander <wwc@mit.edu> 12/09/97
36 // -------------------------------------------------------------------
37 
38 #include "G4ExplicitEuler.hh"
39 #include "G4ThreeVector.hh"
40 
42 //
43 // Constructor
44 
46  G4int numberOfVariables)
47  : G4MagErrorStepper(EqRhs, numberOfVariables)
48 {
49 }
50 
51 
53 //
54 // Destructor
55 
57 {
58 }
59 
60 
62 //
63 //
64 
65 void
67  const G4double dydx[],
68  G4double h,
69  G4double yOut[] )
70 {
71  const G4int numberOfVariables= GetNumberOfVariables();
72 
73  // Initialise time to t0, needed when it is not updated by the integration.
74  // yOut[7] = yIn[7]; // Better to set it to NaN; // TODO
75 
76  G4int i;
77 
78  for(i=0;i< numberOfVariables;i++)
79  {
80  yOut[i] = yIn[i] + h*dydx[i] ; // 1st and only Step
81  }
82 
83  return ;
84 }
void DumbStepper(const G4double y[], const G4double dydx[], G4double h, G4double yout[])
int G4int
Definition: G4Types.hh:78
G4int GetNumberOfVariables() const
G4ExplicitEuler(G4EquationOfMotion *EqRhs, G4int numberOfVariables=6)
double G4double
Definition: G4Types.hh:76