| Geant4 Cross Reference |
1 // 1 //
2 // ******************************************* 2 // ********************************************************************
3 // * License and Disclaimer 3 // * License and Disclaimer *
4 // * 4 // * *
5 // * The Geant4 software is copyright of th 5 // * The Geant4 software is copyright of the Copyright Holders of *
6 // * the Geant4 Collaboration. It is provided 6 // * the Geant4 Collaboration. It is provided under the terms and *
7 // * conditions of the Geant4 Software License 7 // * conditions of the Geant4 Software License, included in the file *
8 // * LICENSE and available at http://cern.ch/ 8 // * LICENSE and available at http://cern.ch/geant4/license . These *
9 // * include a list of copyright holders. 9 // * include a list of copyright holders. *
10 // * 10 // * *
11 // * Neither the authors of this software syst 11 // * Neither the authors of this software system, nor their employing *
12 // * institutes,nor the agencies providing fin 12 // * institutes,nor the agencies providing financial support for this *
13 // * work make any representation or warran 13 // * work make any representation or warranty, express or implied, *
14 // * regarding this software system or assum 14 // * regarding this software system or assume any liability for its *
15 // * use. Please see the license in the file 15 // * use. Please see the license in the file LICENSE and URL above *
16 // * for the full disclaimer and the limitatio 16 // * for the full disclaimer and the limitation of liability. *
17 // * 17 // * *
18 // * This code implementation is the result 18 // * This code implementation is the result of the scientific and *
19 // * technical work of the GEANT4 collaboratio 19 // * technical work of the GEANT4 collaboration. *
20 // * By using, copying, modifying or distri 20 // * By using, copying, modifying or distributing the software (or *
21 // * any work based on the software) you ag 21 // * any work based on the software) you agree to acknowledge its *
22 // * use in resulting scientific publicati 22 // * use in resulting scientific publications, and indicate your *
23 // * acceptance of all terms of the Geant4 Sof 23 // * acceptance of all terms of the Geant4 Software license. *
24 // ******************************************* 24 // ********************************************************************
25 // 25 //
26 // G4ErrorMag_UsualEqRhs implementation <<
27 // 26 //
28 // Created: P.Arce, September 2004. << 27 // $Id: G4ErrorMag_UsualEqRhs.cc 66356 2012-12-18 09:02:32Z gcosmo $
>> 28 //
>> 29 //
>> 30 // --------------------------------------------------------------------
>> 31 // GEANT 4 class implementation file
29 // ------------------------------------------- 32 // --------------------------------------------------------------------
30 33
31 #include "G4ErrorMag_UsualEqRhs.hh" 34 #include "G4ErrorMag_UsualEqRhs.hh"
32 #include "G4ErrorPropagatorData.hh" 35 #include "G4ErrorPropagatorData.hh"
33 36
34 //-------------------------------------------- 37 //---------------------------------------------------------------------
35 38
36 G4ErrorMag_UsualEqRhs::G4ErrorMag_UsualEqRhs( 39 G4ErrorMag_UsualEqRhs::G4ErrorMag_UsualEqRhs( G4MagneticField* MagField )
37 : G4Mag_UsualEqRhs( MagField ) 40 : G4Mag_UsualEqRhs( MagField )
38 { 41 {
39 } 42 }
40 43
41 G4ErrorMag_UsualEqRhs::~G4ErrorMag_UsualEqRhs( << 44 G4ErrorMag_UsualEqRhs::~G4ErrorMag_UsualEqRhs()
>> 45 {
>> 46 }
42 47
43 //-------------------------------------------- 48 //---------------------------------------------------------------------
44 <<
45 void 49 void
46 G4ErrorMag_UsualEqRhs::EvaluateRhsGivenB( cons 50 G4ErrorMag_UsualEqRhs::EvaluateRhsGivenB( const G4double y[],
47 cons 51 const G4double B[3],
48 52 G4double dydx[] ) const
49 { 53 {
50 54
51 G4Mag_UsualEqRhs::EvaluateRhsGivenB(y, B, dy 55 G4Mag_UsualEqRhs::EvaluateRhsGivenB(y, B, dydx );
52 56
53 if(G4ErrorPropagatorData::GetErrorPropagator 57 if(G4ErrorPropagatorData::GetErrorPropagatorData()->GetMode()
54 == G4ErrorMode_PropBackwards) 58 == G4ErrorMode_PropBackwards)
55 { 59 {
56 G4double momentum_mag_square = sqr(y[3]) + 60 G4double momentum_mag_square = sqr(y[3]) + sqr(y[4]) + sqr(y[5]);
57 G4double inv_momentum_magnitude = 1.0 / st 61 G4double inv_momentum_magnitude = 1.0 / std::sqrt( momentum_mag_square );
58 62
59 G4double cof = FCof()*inv_momentum_magnitu 63 G4double cof = FCof()*inv_momentum_magnitude;
60 64
61 dydx[3] = cof*(y[4]*(-B[2]) - y[5]*(-B[1]) 65 dydx[3] = cof*(y[4]*(-B[2]) - y[5]*(-B[1])) ;
62 dydx[4] = cof*(y[5]*(-B[0]) - y[3]*(-B[2]) 66 dydx[4] = cof*(y[5]*(-B[0]) - y[3]*(-B[2])) ;
63 dydx[5] = cof*(y[3]*(-B[1]) - y[4]*(-B[0]) 67 dydx[5] = cof*(y[3]*(-B[1]) - y[4]*(-B[0])) ;
64 } 68 }
65 return; 69 return;
66 } 70 }
67 71