// // ******************************************************************** // * License and Disclaimer * // * * // * The Geant4 software is copyright of the Copyright Holders of * // * the Geant4 Collaboration. It is provided under the terms and * // * conditions of the Geant4 Software License, included in the file * // * LICENSE and available at http://cern.ch/geant4/license . These * // * include a list of copyright holders. * // * * // * Neither the authors of this software system, nor their employing * // * institutes,nor the agencies providing financial support for this * // * work make any representation or warranty, express or implied, * // * regarding this software system or assume any liability for its * // * use. Please see the license in the file LICENSE and URL above * // * for the full disclaimer and the limitation of liability. * // * * // * This code implementation is the result of the scientific and * // * technical work of the GEANT4 collaboration. * // * By using, copying, modifying or distributing the software (or * // * any work based on the software) you agree to acknowledge its * // * use in resulting scientific publications, and indicate your * // * acceptance of all terms of the Geant4 Software license. * // ******************************************************************** // // // $Id: G4MagIntegratorDriver.hh,v 1.20 2007/05/10 10:10:05 japost Exp $ // GEANT4 tag $Name: $ // // // class G4MagInt_Driver // // Class description: // // Provides a driver that talks to the Integrator Stepper, and insures that // the error is within acceptable bounds. // History: // - Created. J.Apostolakis. // -------------------------------------------------------------------- #ifndef G4MagInt_Driver_Def #define G4MagInt_Driver_Def #include "G4Types.hh" #include "G4FieldTrack.hh" #include "G4MagIntegratorStepper.hh" class G4MagInt_Driver { public: // with description G4bool AccurateAdvance(G4FieldTrack& y_current, G4double hstep, G4double eps, // Requested y_err/hstep G4double hinitial=0.0); // Suggested 1st interval // Above drivers for integrator (Runge-Kutta) with stepsize control. // Integrates ODE starting values y_current // from current s (s=s0) to s=s0+h with accuracy eps. // On output ystart is replaced by value at end of interval. // The concept is similar to the odeint routine from NRC p.721-722. G4bool QuickAdvance( G4FieldTrack& y_val, // INOUT const G4double dydx[], G4double hstep, // IN G4double& dchord_step, G4double& dyerr ) ; // QuickAdvance just tries one Step - it does not ensure accuracy. G4bool QuickAdvance( G4FieldTrack& y_posvel, // INOUT const G4double dydx[], G4double hstep, // IN G4double& dchord_step, G4double& dyerr_pos_sq, G4double& dyerr_mom_rel_sq ) ; // New QuickAdvance that also just tries one Step // (so also does not ensure accuracy) // but does return the errors in position and // momentum (normalised: Delta_Integration(p^2)/(p^2) ) G4MagInt_Driver( G4double hminimum, G4MagIntegratorStepper *pItsStepper, G4int numberOfComponents=6, G4int statisticsVerbosity=1); ~G4MagInt_Driver(); // Constructor, destructor. inline G4double GetHmin() const; inline G4double Hmin() const; // Obsolete inline G4double GetSafety() const; inline G4double GetPshrnk() const; inline G4double GetPgrow() const; inline G4double GetErrcon() const; inline void GetDerivatives( const G4FieldTrack &y_curr, // const, INput G4double dydx[] ); // OUTput // Accessors. inline void RenewStepperAndAdjust(G4MagIntegratorStepper *pItsStepper); // Sets a new stepper pItsStepper for this driver. Then it calls // ReSetParameters to reset its parameters accordingly. inline void ReSetParameters(G4double new_safety= 0.9 ); // i) sets the exponents (pgrow & pshrnk), // using the current Stepper's order, // ii) sets the safety // ii) calculates "errcon" according to the above values. inline void SetSafety(G4double valS); inline void SetPshrnk(G4double valPs); inline void SetPgrow (G4double valPg); inline void SetErrcon(G4double valEc); // When setting safety or pgrow, errcon will be set to a // compatible value. inline G4double ComputeAndSetErrcon(); inline void SetChargeMomentumMass( G4double particleCharge, G4double MomentumXc, G4double Mass ); // Change them in Equation. particleCharge is in e+ units. inline const G4MagIntegratorStepper* GetStepper() const; void OneGoodStep( G4double ystart[], // Like old RKF45step() const G4double dydx[], G4double& x, G4double htry, G4double eps, // memb variables ? G4double& hdid, G4double& hnext ) ; // This takes one Step that is as large as possible while // satisfying the accuracy criterion of: // yerr < eps * |y_end-y_start| G4double ComputeNewStepSize( G4double errMaxNorm, // normalised error G4double hstepCurrent); // current step size // Taking the last step's normalised error, calculate // a step size for the next step. // Do not limit the next step's size within a factor of the // current one. G4double ComputeNewStepSize_WithinLimits( G4double errMaxNorm, // normalised error G4double hstepCurrent); // current step size // Taking the last step's normalised error, calculate // a step size for the next step. // Limit the next step's size within a range around the current one. inline G4int GetMaxNoSteps() const; inline void SetMaxNoSteps( G4int val); // Modify and Get the Maximum number of Steps that can be // taken for the integration of a single segment - // (ie a single call to AccurateAdvance). public: // without description inline void SetHmin(G4double newval); inline void SetVerboseLevel(G4int newLevel); inline G4double GetVerboseLevel() const; inline G4double GetSmallestFraction() const; void SetSmallestFraction( G4double val ); protected: // without description void WarnSmallStepSize( G4double hnext, G4double hstep, G4double h, G4double xDone, G4int noSteps); void WarnTooManyStep( G4double x1start, G4double x2end, G4double xCurrent); void WarnEndPointTooFar (G4double endPointDist, G4double hStepSize , G4double epsilonRelative, G4int debugFlag); // Issue warnings for undesirable situations void PrintStatus( const G4double* StartArr, G4double xstart, const G4double* CurrentArr, G4double xcurrent, G4double requestStep, G4int subStepNo ); void PrintStatus( const G4FieldTrack& StartFT, const G4FieldTrack& CurrentFT, G4double requestStep, G4int subStepNo ); void PrintStat_Aux( const G4FieldTrack& aFieldTrack, G4double requestStep, G4double actualStep, G4int subStepNo, G4double subStepSize, G4double dotVelocities ); // Verbose output for debugging void PrintStatisticsReport() ; // Report on the number of steps, maximum errors etc. #ifdef QUICK_ADV_TWO G4bool QuickAdvance( G4double yarrin[], // In const G4double dydx[], G4double hstep, G4double yarrout[], // Out G4double& dchord_step, // Out G4double& dyerr ); // in length #endif private: G4MagInt_Driver(const G4MagInt_Driver&); G4MagInt_Driver& operator=(const G4MagInt_Driver&); // Private copy constructor and assignment operator. private: G4double fMinimumStep; // Minimum Step allowed in a Step (in absolute units) G4double fSmallestFraction; // Expected range 1e-12 to 5e-15; // Smallest fraction of (existing) curve length - in relative units // below this fraction the current step will be the last const G4int fNoIntegrationVariables; // Number of Variables in integration const G4int fMinNoVars; // Minimum number for FieldTrack const G4int fNoVars; // Full number of variable G4MagIntegratorStepper *pIntStepper; G4int fMaxNoSteps; static const G4int fMaxStepBase; G4double safety; G4double pshrnk; // exponent for shrinking G4double pgrow; // exponent for growth G4double errcon; // Parameters used to grow and shrink trial stepsize. static const G4double max_stepping_increase; static const G4double max_stepping_decrease; // Maximum stepsize increase/decrease factors. G4int fVerboseLevel; // Verbosity level for printing (debug, ..) G4int fNoTotalSteps, fNoBadSteps, fNoSmallSteps, fNoInitialSmallSteps; G4double fDyerr_max, fDyerr_mx2; G4double fDyerrPos_smTot, fDyerrVel_smTot, fDyerrPos_lgTot, fDyerrVel_lgTot; G4double fSumH_sm, fSumH_lg; // Step Statistics G4int fStatisticsVerboseLevel; }; #include "G4MagIntegratorDriver.icc" #endif /* G4MagInt_Driver_Def */