Geant4 Cross Reference |
1 // 1 // 2 // ******************************************* 2 // ******************************************************************** 3 // * License and Disclaimer << 3 // * DISCLAIMER * 4 // * 4 // * * 5 // * The Geant4 software is copyright of th << 5 // * The following disclaimer summarizes all the specific disclaimers * 6 // * the Geant4 Collaboration. It is provided << 6 // * of contributors to this software. The specific disclaimers,which * 7 // * conditions of the Geant4 Software License << 7 // * govern, are listed with their locations in: * 8 // * LICENSE and available at http://cern.ch/ << 8 // * http://cern.ch/geant4/license * 9 // * include a list of copyright holders. << 10 // * 9 // * * 11 // * Neither the authors of this software syst 10 // * Neither the authors of this software system, nor their employing * 12 // * institutes,nor the agencies providing fin 11 // * institutes,nor the agencies providing financial support for this * 13 // * work make any representation or warran 12 // * work make any representation or warranty, express or implied, * 14 // * regarding this software system or assum 13 // * regarding this software system or assume any liability for its * 15 // * use. Please see the license in the file << 14 // * use. * 16 // * for the full disclaimer and the limitatio << 17 // * 15 // * * 18 // * This code implementation is the result << 16 // * This code implementation is the intellectual property of the * 19 // * technical work of the GEANT4 collaboratio << 17 // * GEANT4 collaboration. * 20 // * By using, copying, modifying or distri << 18 // * By copying, distributing or modifying the Program (or any work * 21 // * any work based on the software) you ag << 19 // * based on the Program) you indicate your acceptance of this * 22 // * use in resulting scientific publicati << 20 // * statement, and all its terms. * 23 // * acceptance of all terms of the Geant4 Sof << 24 // ******************************************* 21 // ******************************************************************** 25 // 22 // 26 // G4HelixImplicitEuler implementation << 23 // >> 24 // $Id: G4HelixImplicitEuler.cc,v 1.4 2001/07/11 09:59:12 gunter Exp $ >> 25 // GEANT4 tag $Name: geant4-05-02 $ >> 26 // >> 27 #include "G4HelixImplicitEuler.hh" >> 28 #include "G4ThreeVector.hh" >> 29 27 // 30 // 28 // Helix Implicit Euler: 31 // Helix Implicit Euler: 29 // x_1 = x_0 + 1/2 * ( helix(h,t_0,x_0) 32 // x_1 = x_0 + 1/2 * ( helix(h,t_0,x_0) 30 // + helix(h,t_0+h,x_ 33 // + helix(h,t_0+h,x_0+helix(h,t0,x0) ) ) 31 // Second order solver. << 34 // W.Wander <wwc@mit.edu> 12/09/97 32 // Take the current derivative and add it to << 33 // Take the output and its derivative. Add th << 34 // to form the final output << 35 // 35 // 36 // Author: W.Wander <wwc@mit.edu>, 03/11/1998 << 37 // ------------------------------------------- << 38 36 39 #include "G4HelixImplicitEuler.hh" << 37 // ------------------------------------------------------------------------- 40 #include "G4ThreeVector.hh" << 41 38 42 G4HelixImplicitEuler::G4HelixImplicitEuler(G4M << 39 // second order solver 43 : G4MagHelicalStepper(EqRhs) << 40 // Take the current derivative and add it to the current position. 44 { << 41 // Take the output and its derivative. Add the mean of both derivatives 45 } << 42 // to form the final output >> 43 // 46 44 47 G4HelixImplicitEuler::~G4HelixImplicitEuler() << 48 << 49 void 45 void 50 G4HelixImplicitEuler::DumbStepper( const G4dou << 46 G4HelixImplicitEuler::DumbStepper( const G4double yIn[], 51 G4ThreeVect << 47 G4ThreeVector Bfld, 52 G4double << 48 G4double h, 53 G4double << 49 G4double yOut[]) 54 { 50 { 55 const G4int nvar = 6 ; 51 const G4int nvar = 6 ; 56 G4double yTemp[6], yTemp2[6]; 52 G4double yTemp[6], yTemp2[6]; 57 G4ThreeVector Bfld_endpoint; 53 G4ThreeVector Bfld_endpoint; 58 54 >> 55 G4int i; >> 56 59 // Step forward like in the explicit euler c 57 // Step forward like in the explicit euler case 60 // << 61 AdvanceHelix( yIn, Bfld, h, yTemp); 58 AdvanceHelix( yIn, Bfld, h, yTemp); 62 59 63 // now obtain the new field value at the new 60 // now obtain the new field value at the new point 64 // << 65 MagFieldEvaluate(yTemp, Bfld_endpoint); 61 MagFieldEvaluate(yTemp, Bfld_endpoint); 66 62 67 // and also advance along a helix for this f 63 // and also advance along a helix for this field value 68 // << 69 AdvanceHelix( yIn, Bfld_endpoint, h, yTemp2) 64 AdvanceHelix( yIn, Bfld_endpoint, h, yTemp2); 70 65 71 // we take the average << 66 // we take the average 72 // << 67 for( i = 0; i < nvar; i++ ) 73 for( G4int i = 0; i < nvar; ++i ) << 74 { << 75 yOut[i] = 0.5 * ( yTemp[i] + yTemp2[i] ); 68 yOut[i] = 0.5 * ( yTemp[i] + yTemp2[i] ); 76 } << 77 69 78 // NormaliseTangentVector( yOut ); 70 // NormaliseTangentVector( yOut ); >> 71 >> 72 return ; 79 } 73 } 80 74