Geant4: G4ChordFinderSaf Class Reference

G4ChordFinderSaf::G4ChordFinderSaf ( G4MagInt_Driver * pIntegrationDriver )

Definition at line 33 of file G4ChordFinderSaf.cc.

00034   : G4ChordFinder(pIntegrationDriver)
00035 {
00036     // check the values and set the other parameters
00037     // fNoInitialRadBig=0;    fNoInitialRadSmall=0;  
00038     // fNoTrialsRadBig=0;     fNoTrialsRadSmall=0; 
00039    
00040 }

G4ChordFinderSaf::G4ChordFinderSaf	(	G4MagneticField *	theMagField,
		G4double	stepMinimum,
		G4MagIntegratorStepper *	pItsStepper
	)

Definition at line 44 of file G4ChordFinderSaf.cc.

00047   : G4ChordFinder( theMagField, stepMinimum, pItsStepper )
00048 {
00049   //  Let  G4ChordFinder create the  Driver, the Stepper and EqRhs ...
00050   // ...
00051 }

G4ChordFinderSaf::~G4ChordFinderSaf ( )

Definition at line 57 of file G4ChordFinderSaf.cc.

References PrintStatistics(), and G4ChordFinder::SetVerbose().

00058 {
00059   if( SetVerbose(0) ) { PrintStatistics();  } 
00060    // Set verbosity 0, so that will be called in base class again
00061 }

G4double G4ChordFinderSaf::FindNextChord	(	const G4FieldTrack &	yStart,
		G4double	stepMax,
		G4FieldTrack &	yEnd,
		G4double &	dyErrPos,
		G4double	epsStep,
		G4double *	pStepForAccuracy,
		const G4ThreeVector	latestSafetyOrigin,
		G4double	latestSafetyRadius
	)			`[virtual]`

Reimplemented from G4ChordFinder.

Definition at line 118 of file G4ChordFinderSaf.cc.

References G4ChordFinder::AcceptableMissDist(), G4ChordFinder::AccumulateStatistics(), CalculatePointInside(), CalculatePointSafety(), G4MagInt_Driver::ComputeNewStepSize(), G4cout, G4endl, G4ChordFinder::GetFirstFraction(), G4ChordFinder::GetFractionLast(), G4ChordFinder::GetIntegrationDriver(), G4ChordFinder::GetLastStepEstimateUnc(), G4FieldTrack::GetPosition(), G4FieldTrack::ncompSVEC, G4ChordFinder::NewStep(), G4MagInt_Driver::QuickAdvance(), and G4ChordFinder::SetLastStepEstimateUnc().

00128 {
00129   // G4int       stepRKnumber=0;
00130   G4FieldTrack yCurrent=  yStart;  
00131   G4double    stepTrial, stepForAccuracy;
00132   G4double    dydx[G4FieldTrack::ncompSVEC]; 
00133 
00134   //  1.)  Try to "leap" to end of interval
00135   //  2.)  Evaluate if resulting chord gives d_chord that is good enough.
00136   //     2a.)  If d_chord is not good enough, find one that is.
00137   
00138   G4bool    validEndPoint= false;
00139   G4double  dChordStep, lastStepLength; //  stepOfLastGoodChord;
00140 
00141   GetIntegrationDriver()-> GetDerivatives( yCurrent, dydx )  ;
00142 
00143   G4int     noTrials=0;
00144   const G4double safetyFactor= GetFirstFraction(); // was 0.999
00145 
00146   // Figure out the starting safety
00147   G4double      startSafety=  
00148     CalculatePointSafety( latestSafetyOrigin, 
00149                           latestSafetyRadius, 
00150                           yCurrent.GetPosition() );
00151 
00152   G4double
00153     likelyGood = std::max( startSafety , 
00154                         safetyFactor *  GetLastStepEstimateUnc() );
00155 
00156   stepTrial  = std::min( stepMax,  likelyGood ); 
00157 
00158   G4MagInt_Driver *pIntgrDriver= G4ChordFinder::GetIntegrationDriver(); 
00159   G4double newStepEst_Uncons= 0.0; 
00160   do
00161   { 
00162      G4double stepForChord;  
00163      yCurrent = yStart;    // Always start from initial point
00164 
00165    //            ************
00166      pIntgrDriver->QuickAdvance( yCurrent, dydx, stepTrial, 
00167                                  dChordStep, dyErrPos);
00168      //            ************
00169 
00170      G4ThreeVector EndPointCand= yCurrent.GetPosition(); 
00171      G4bool  endPointInSafetySphere= 
00172        CalculatePointInside(latestSafetyOrigin, latestSafetyRadius, EndPointCand);
00173 
00174      // We check whether the criterion is met here.
00175      validEndPoint = AcceptableMissDist(dChordStep)
00176                        || endPointInSafetySphere;
00177                       //  && (dyErrPos < eps) ;
00178 
00179      lastStepLength = stepTrial; 
00180 
00181      // This method estimates to step size for a good chord.
00182      stepForChord = NewStep(stepTrial, dChordStep, newStepEst_Uncons );
00183 
00184      if( ! validEndPoint ) {
00185         if( stepTrial<=0.0 )
00186           stepTrial = stepForChord; 
00187         else if (stepForChord <= stepTrial) 
00188           // Reduce by a fraction, possibly up to 20% 
00189           stepTrial = std::min( stepForChord, 
00190                                 GetFractionLast() * stepTrial); 
00191         else
00192           stepTrial *= 0.1;
00193 
00194         // if(dbg) G4cerr<<"Dchord too big. Try new hstep="<<stepTrial<<G4endl;
00195      }
00196      // #ifdef  TEST_CHORD_PRINT
00197      // TestChordPrint( noTrials, lastStepLength, dChordStep, stepTrial );
00198      // #endif
00199 
00200      noTrials++; 
00201   }
00202   while( ! validEndPoint );   // End of do-while  RKD 
00203 
00204   AccumulateStatistics( noTrials );
00205 
00206   // Should we update newStepEst_Uncons for a 'long step' via safety ??
00207   if( newStepEst_Uncons > 0.0  ){ 
00208     SetLastStepEstimateUnc( newStepEst_Uncons );
00209   }
00210 
00211   // stepOfLastGoodChord = stepTrial;
00212 
00213   if( pStepForAccuracy ){ 
00214      // Calculate the step size required for accuracy, if it is needed
00215      G4double dyErr_relative = dyErrPos/(epsStep*lastStepLength);
00216      if( dyErr_relative > 1.0 ) {
00217         stepForAccuracy =
00218            pIntgrDriver->ComputeNewStepSize( dyErr_relative,
00219                                              lastStepLength );
00220      }else{
00221         stepForAccuracy = 0.0;   // Convention to show step was ok 
00222      }
00223      *pStepForAccuracy = stepForAccuracy;
00224   }
00225 
00226 #ifdef  TEST_CHORD_PRINT
00227   static int dbg=0;
00228   if( dbg ) 
00229     G4cout << "ChordF/FindNextChord:  NoTrials= " << noTrials 
00230            << " StepForGoodChord=" << std::setw(10) << stepTrial << G4endl;
00231 #endif
00232 
00233   yEnd=  yCurrent;  
00234   return stepTrial; 
00235 }

void G4ChordFinderSaf::PrintStatistics ( ) [virtual]

Reimplemented from G4ChordFinder.

Definition at line 64 of file G4ChordFinderSaf.cc.

References G4cout, G4endl, and G4ChordFinder::PrintStatistics().

Referenced by ~G4ChordFinderSaf().

00065 {
00066   // Print Statistics
00067   G4cout << "G4ChordFinderSaf statistics report: " << G4endl;
00068   G4ChordFinder::PrintStatistics();
00069 
00070 /*******************
00071   G4cout 
00072     << "  No radbig calls " << std::setw(10) << fNoInitialRadBig 
00073     << " trials " << std::setw(10) << fNoTrialsRadBig
00074     << "  - over " << std::setw(10) << fNoTrialsRadBig - fNoInitialRadBig
00075     << G4endl
00076     << "  No radsm  calls " << std::setw(10) << fNoInitialRadSmall 
00077     << " trials "  << std::setw(10) << fNoTrialsRadSmall
00078     << "  - over " << std::setw(10) << fNoTrialsRadSmall - fNoInitialRadSmall
00079     << G4endl;
00080   G4cout
00081     << "  *** Limiting stepTrial via if Delta_chord < R_curvature " 
00082     << "   for large to angle from Delta_chord / R_curv "  
00083     << "   and for small with multiple " << GetMultipleRadius()
00084     << G4endl; 
00085 ********************/
00086 }


Public Member Functions
	G4ChordFinderSaf (G4MagInt_Driver *pIntegrationDriver)
	G4ChordFinderSaf (G4MagneticField theMagField, G4double stepMinimum, G4MagIntegratorStepper pItsStepper)
	~G4ChordFinderSaf ()
G4double	FindNextChord (const G4FieldTrack &yStart, G4double stepMax, G4FieldTrack &yEnd, G4double &dyErrPos, G4double epsStep, G4double *pStepForAccuracy, const G4ThreeVector latestSafetyOrigin, G4double latestSafetyRadius)
void	PrintStatistics ()

G4ChordFinderSaf Class Reference

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation