Gabriele Cosmo
84 lines
2.9 KiB
C++
84 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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//
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//
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//
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// Explicit Euler: x_1 = x_0 + h * dx_0
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//
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// most simple approach for solving linear differential equations.
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// Take the current derivative and add it to the current position.
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//
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// W.Wander <wwc@mit.edu> 12/09/97
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// -------------------------------------------------------------------
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#include "G4ExplicitEuler.hh"
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#include "G4ThreeVector.hh"
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//////////////////////////////////////////////////////////////////////////
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//
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// Constructor
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G4ExplicitEuler::G4ExplicitEuler(G4EquationOfMotion* EqRhs,
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G4int numberOfVariables)
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: G4MagErrorStepper(EqRhs, numberOfVariables)
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{
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}
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///////////////////////////////////////////////////////////////////////
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//
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// Destructor
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G4ExplicitEuler::~G4ExplicitEuler()
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{
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}
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///////////////////////////////////////////////////////////////////////
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//
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//
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void
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G4ExplicitEuler::DumbStepper( const G4double yIn[],
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const G4double dydx[],
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G4double h,
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G4double yOut[] )
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{
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const G4int numberOfVariables= GetNumberOfVariables();
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// Initialise time to t0, needed when it is not updated by the integration.
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// yOut[7] = yIn[7]; // Better to set it to NaN; // TODO
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G4int i;
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for(i=0;i< numberOfVariables;i++)
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{
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yOut[i] = yIn[i] + h*dydx[i] ; // 1st and only Step
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}
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return ;
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}
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