| [831] | 1 | //
|
|---|
| 2 | // ********************************************************************
|
|---|
| 3 | // * License and Disclaimer *
|
|---|
| 4 | // * *
|
|---|
| 5 | // * The Geant4 software is copyright of the Copyright Holders of *
|
|---|
| 6 | // * the Geant4 Collaboration. It is provided under the terms and *
|
|---|
| 7 | // * conditions of the Geant4 Software License, included in the file *
|
|---|
| 8 | // * LICENSE and available at http://cern.ch/geant4/license . These *
|
|---|
| 9 | // * include a list of copyright holders. *
|
|---|
| 10 | // * *
|
|---|
| 11 | // * Neither the authors of this software system, nor their employing *
|
|---|
| 12 | // * institutes,nor the agencies providing financial support for this *
|
|---|
| 13 | // * work make any representation or warranty, express or implied, *
|
|---|
| 14 | // * regarding this software system or assume any liability for its *
|
|---|
| 15 | // * use. Please see the license in the file LICENSE and URL above *
|
|---|
| 16 | // * for the full disclaimer and the limitation of liability. *
|
|---|
| 17 | // * *
|
|---|
| 18 | // * This code implementation is the result of the scientific and *
|
|---|
| 19 | // * technical work of the GEANT4 collaboration. *
|
|---|
| 20 | // * By using, copying, modifying or distributing the software (or *
|
|---|
| 21 | // * any work based on the software) you agree to acknowledge its *
|
|---|
| 22 | // * use in resulting scientific publications, and indicate your *
|
|---|
| 23 | // * acceptance of all terms of the Geant4 Software license. *
|
|---|
| 24 | // ********************************************************************
|
|---|
| 25 | //
|
|---|
| 26 | //
|
|---|
| 27 | // $Id: G4ClassicalRK4.hh,v 1.10 2006/06/29 18:21:55 gunter Exp $
|
|---|
| [921] | 28 | // GEANT4 tag $Name: geant4-09-02-cand-01 $
|
|---|
| [831] | 29 | //
|
|---|
| 30 | //
|
|---|
| 31 | // class G4ClassicalRK4
|
|---|
| 32 | //
|
|---|
| 33 | // Class description:
|
|---|
| 34 | //
|
|---|
| 35 | // Integrate the equations of the motion of a particle in a magnetic field
|
|---|
| 36 | // using the classical 4th Runge-Kutta method.
|
|---|
| 37 |
|
|---|
| 38 | // History:
|
|---|
| 39 | // - Created: J.Apostolakis, V.Grichine - 30.1.97
|
|---|
| 40 | // - Moved into G4MagErrorStepper: W.Wander <wwc@mit.edu> - 12/09/97
|
|---|
| 41 | // -------------------------------------------------------------------
|
|---|
| 42 |
|
|---|
| 43 | #include "G4MagErrorStepper.hh"
|
|---|
| 44 |
|
|---|
| 45 | class G4ClassicalRK4 : public G4MagErrorStepper
|
|---|
| 46 | {
|
|---|
| 47 | public: // with description
|
|---|
| 48 |
|
|---|
| 49 | G4ClassicalRK4(G4EquationOfMotion *EquationMotion, G4int numberOfVariables = 6) ;
|
|---|
| 50 |
|
|---|
| 51 | ~G4ClassicalRK4() ;
|
|---|
| 52 |
|
|---|
| 53 | // A stepper that does not know about errors.
|
|---|
| 54 | // It is used by the MagErrorStepper stepper.
|
|---|
| 55 |
|
|---|
| 56 | void DumbStepper( const G4double yIn[],
|
|---|
| 57 | const G4double dydx[],
|
|---|
| 58 | G4double h,
|
|---|
| 59 | G4double yOut[] ) ;
|
|---|
| 60 | // Given values for the variables y[0,..,n-1] and their derivatives
|
|---|
| 61 | // dydx[0,...,n-1] known at x, use the classical 4th Runge-Kutta
|
|---|
| 62 | // method to advance the solution over an interval h and return the
|
|---|
| 63 | // incremented variables as yout[0,...,n-1], which not be a distinct
|
|---|
| 64 | // array from y. The user supplies the routine RightHandSide(x,y,dydx),
|
|---|
| 65 | // which returns derivatives dydx at x. The source is routine rk4 from
|
|---|
| 66 | // NRC p. 712-713 .
|
|---|
| 67 |
|
|---|
| 68 | public: // without description
|
|---|
| 69 |
|
|---|
| 70 | G4int IntegratorOrder() const { return 4; }
|
|---|
| 71 |
|
|---|
| 72 | private:
|
|---|
| 73 |
|
|---|
| 74 | void StepWithEst( const G4double yIn[],
|
|---|
| 75 | const G4double dydx[],
|
|---|
| 76 | G4double h,
|
|---|
| 77 | G4double yOut[],
|
|---|
| 78 | G4double& alpha2,
|
|---|
| 79 | G4double& beta2,
|
|---|
| 80 | const G4double B1[],
|
|---|
| 81 | G4double B2[] );
|
|---|
| 82 | // No longer used. Obsolete.
|
|---|
| 83 |
|
|---|
| 84 | G4ClassicalRK4(const G4ClassicalRK4&);
|
|---|
| 85 | G4ClassicalRK4& operator=(const G4ClassicalRK4&);
|
|---|
| 86 | // Private copy constructor and assignment operator.
|
|---|
| 87 |
|
|---|
| 88 | private:
|
|---|
| 89 |
|
|---|
| 90 | // G4int fNumberOfVariables ; // is set default to 6 in constructor
|
|---|
| 91 |
|
|---|
| 92 | G4double *dydxm, *dydxt, *yt; // scratch space - not state
|
|---|
| 93 | };
|
|---|
