G4HelixHeum.cc

Go to the documentation of this file.
00001 //
00002 // ********************************************************************
00003 // * License and Disclaimer                                           *
00004 // *                                                                  *
00005 // * The  Geant4 software  is  copyright of the Copyright Holders  of *
00006 // * the Geant4 Collaboration.  It is provided  under  the terms  and *
00007 // * conditions of the Geant4 Software License,  included in the file *
00008 // * LICENSE and available at  http://cern.ch/geant4/license .  These *
00009 // * include a list of copyright holders.                             *
00010 // *                                                                  *
00011 // * Neither the authors of this software system, nor their employing *
00012 // * institutes,nor the agencies providing financial support for this *
00013 // * work  make  any representation or  warranty, express or implied, *
00014 // * regarding  this  software system or assume any liability for its *
00015 // * use.  Please see the license in the file  LICENSE  and URL above *
00016 // * for the full disclaimer and the limitation of liability.         *
00017 // *                                                                  *
00018 // * This  code  implementation is the result of  the  scientific and *
00019 // * technical work of the GEANT4 collaboration.                      *
00020 // * By using,  copying,  modifying or  distributing the software (or *
00021 // * any work based  on the software)  you  agree  to acknowledge its *
00022 // * use  in  resulting  scientific  publications,  and indicate your *
00023 // * acceptance of all terms of the Geant4 Software license.          *
00024 // ********************************************************************
00025 //
00026 //
00027 // $Id: G4HelixHeum.cc 69786 2013-05-15 09:38:51Z gcosmo $
00028 //
00029 //
00030 //  Simple Heum:
00031 //        x_1 = x_0 + h *
00032 //                1/4 * dx(t0,x0)  +
00033 //                3/4 * dx(t0+2/3*h, x0+2/3*h*(dx(t0+h/3,x0+h/3*dx(t0,x0)))) 
00034 //
00035 //  Third order solver.
00036 //
00037 //  W.Wander <wwc@mit.edu> 12/09/97 
00038 // -------------------------------------------------------------------
00039 
00040 #include "G4HelixHeum.hh"
00041 #include "G4ThreeVector.hh"
00042 
00043 void
00044 G4HelixHeum::DumbStepper( const G4double  yIn[],
00045                           G4ThreeVector   Bfld,
00046                           G4double        h,
00047                           G4double        yOut[])
00048 {
00049   const G4int nvar = 6 ;
00050 
00051   G4ThreeVector Bfield_Temp, Bfield_Temp2;
00052   G4double yTemp[6], yAdd1[6], yAdd2[6] , yTemp2[6];
00053 
00054   G4int i;
00055 
00056   AdvanceHelix( yIn, Bfld, h, yAdd1 );
00057   
00058   AdvanceHelix( yIn, Bfld, h/3.0, yTemp );
00059   MagFieldEvaluate(yTemp,Bfield_Temp);
00060 
00061   AdvanceHelix( yIn, Bfield_Temp, (2.0 / 3.0) * h, yTemp2 );
00062   
00063   MagFieldEvaluate(yTemp2,Bfield_Temp2);
00064 
00065   AdvanceHelix( yIn, Bfield_Temp2, h, yAdd2 );
00066 
00067   for( i = 0; i < nvar; i++ ) {
00068     yOut[i] = ( 0.25 * yAdd1[i] + 0.75 * yAdd2[i]);
00069   }
00070 
00071   // NormaliseTangentVector( yOut );           
00072 }  

Generated on Mon May 27 17:48:29 2013 for Geant4 by  doxygen 1.4.7