Gabriele Cosmo
77 lines
2.9 KiB
C++
77 lines
2.9 KiB
C++
//
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// ********************************************************************
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// * License and Disclaimer *
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// * *
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// * The Geant4 software is copyright of the Copyright Holders of *
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// * the Geant4 Collaboration. It is provided under the terms and *
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// * conditions of the Geant4 Software License, included in the file *
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// * LICENSE and available at http://cern.ch/geant4/license . These *
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// * include a list of copyright holders. *
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// * *
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// * Neither the authors of this software system, nor their employing *
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// * institutes,nor the agencies providing financial support for this *
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// * work make any representation or warranty, express or implied, *
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// * regarding this software system or assume any liability for its *
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// * use. Please see the license in the file LICENSE and URL above *
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// * for the full disclaimer and the limitation of liability. *
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// * *
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// * This code implementation is the result of the scientific and *
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// * technical work of the GEANT4 collaboration. *
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// * By using, copying, modifying or distributing the software (or *
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// * any work based on the software) you agree to acknowledge its *
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// * use in resulting scientific publications, and indicate your *
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// * acceptance of all terms of the Geant4 Software license. *
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// ********************************************************************
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//
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// G4HelixHeum implementation
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//
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// Simple Heum:
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// x_1 = x_0 + h *
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// 1/4 * dx(t0,x0) +
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// 3/4 * dx(t0+2/3*h, x0+2/3*h*(dx(t0+h/3,x0+h/3*dx(t0,x0))))
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//
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// Third order solver.
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//
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// Author: W.Wander <wwc@mit.edu>, 03/11/1998
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// -------------------------------------------------------------------
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#include "G4HelixHeum.hh"
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#include "G4ThreeVector.hh"
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G4HelixHeum::G4HelixHeum(G4Mag_EqRhs* EqRhs)
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: G4MagHelicalStepper(EqRhs)
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{
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}
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G4HelixHeum::~G4HelixHeum() = default;
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void
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G4HelixHeum::DumbStepper( const G4double yIn[],
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G4ThreeVector Bfld,
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G4double h,
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G4double yOut[])
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{
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const G4int nvar = 6 ;
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G4ThreeVector Bfield_Temp, Bfield_Temp2;
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G4double yTemp[6], yAdd1[6], yAdd2[6] , yTemp2[6];
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AdvanceHelix( yIn, Bfld, h, yAdd1 );
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AdvanceHelix( yIn, Bfld, h/3.0, yTemp );
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MagFieldEvaluate(yTemp,Bfield_Temp);
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AdvanceHelix( yIn, Bfield_Temp, (2.0 / 3.0) * h, yTemp2 );
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MagFieldEvaluate(yTemp2,Bfield_Temp2);
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AdvanceHelix( yIn, Bfield_Temp2, h, yAdd2 );
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for( G4int i = 0; i < nvar; ++i )
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{
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yOut[i] = ( 0.25 * yAdd1[i] + 0.75 * yAdd2[i]);
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}
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// NormaliseTangentVector( yOut );
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}
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