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Geant4/geometry/magneticfield/src/G4ChordFinder.cc

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Differences between /geometry/magneticfield/src/G4ChordFinder.cc (Version 11.3.0) and /geometry/magneticfield/src/G4ChordFinder.cc (Version 10.3.p2)


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 25 //                                                 25 //
 26 // G4ChordFinder implementation                << 
 27 //                                                 26 //
 28 // Author: J.Apostolakis - Design and implemen <<  27 // $Id: G4ChordFinder.cc 101384 2016-11-16 11:03:44Z gcosmo $
                                                   >>  28 //
                                                   >>  29 //
                                                   >>  30 // 25.02.97 - John Apostolakis - Design and implementation 
 29 // -------------------------------------------     31 // -------------------------------------------------------------------
 30                                                    32 
 31 #include <iomanip>                                 33 #include <iomanip>
 32                                                    34 
 33 #include "G4ChordFinder.hh"                        35 #include "G4ChordFinder.hh"
 34 #include "G4SystemOfUnits.hh"                      36 #include "G4SystemOfUnits.hh"
 35 #include "G4MagneticField.hh"                      37 #include "G4MagneticField.hh"
 36 #include "G4Mag_UsualEqRhs.hh"                     38 #include "G4Mag_UsualEqRhs.hh"
 37 #include "G4MagIntegratorDriver.hh"            <<  39 #include "G4ClassicalRK4.hh"
 38 // #include "G4ClassicalRK4.hh"                <<  40 #include "G4CashKarpRKF45.hh"
 39 // #include "G4CashKarpRKF45.hh"               << 
 40 // #include "G4NystromRK4.hh"                  << 
 41 // #include "G4BogackiShampine23.hh"               41 // #include "G4BogackiShampine23.hh"
 42 // #include "G4BogackiShampine45.hh"           <<  42 #include "G4BogackiShampine45.hh"
 43                                                << 
 44 #include "G4DormandPrince745.hh"                   43 #include "G4DormandPrince745.hh"
 45                                                    44 
 46 // New templated stepper(s) -- avoid virtual c <<  45 // ..........................................................................
 47 #include "G4TDormandPrince45.hh"               << 
 48                                                << 
 49 // FSAL type driver / steppers -----           << 
 50 #include "G4FSALIntegrationDriver.hh"          << 
 51 #include "G4VFSALIntegrationStepper.hh"        << 
 52 #include "G4RK547FEq1.hh"                      << 
 53 // #include "G4RK547FEq2.hh"                   << 
 54 // #include "G4RK547FEq3.hh"                   << 
 55 // #include "G4FSALBogackiShampine45.hh"       << 
 56 // #include "G4FSALDormandPrince745.hh"        << 
 57                                                << 
 58 // Templated type drivers -----                << 
 59 #include "G4IntegrationDriver.hh"              << 
 60 #include "G4InterpolationDriver.hh"            << 
 61                                                    46 
 62 #include "G4HelixHeum.hh"                      <<  47 G4ChordFinder::G4ChordFinder(G4MagInt_Driver* pIntegrationDriver)
 63 #include "G4BFieldIntegrationDriver.hh"        <<  48   : fDefaultDeltaChord( 0.25 * mm ),      // Parameters
                                                   >>  49     fDeltaChord( fDefaultDeltaChord ),    //   Internal parameters
                                                   >>  50     fFirstFraction(0.999), fFractionLast(1.00),  fFractionNextEstimate(0.98), 
                                                   >>  51     fMultipleRadius(15.0), 
                                                   >>  52     fStatsVerbose(0),
                                                   >>  53     fDriversStepper(0),                    // Dependent objects 
                                                   >>  54     fAllocatedStepper(false),
                                                   >>  55     fEquation(0),      
                                                   >>  56     fTotalNoTrials_FNC(0), fNoCalls_FNC(0), fmaxTrials_FNC(0)
                                                   >>  57 {
                                                   >>  58   // Simple constructor -- it does not create equation
                                                   >>  59   fIntgrDriver= pIntegrationDriver;
                                                   >>  60   fAllocatedStepper= false;
 64                                                    61 
 65 #include "G4QSSDriverCreator.hh"               <<  62   fLastStepEstimate_Unconstrained = DBL_MAX;          // Should move q, p to
 66                                                    63 
 67 #include "G4CachedMagneticField.hh"            <<  64   SetFractions_Last_Next( fFractionLast, fFractionNextEstimate);  
                                                   >>  65     // check the values and set the other parameters
                                                   >>  66 }
 68                                                    67 
 69 #include <cassert>                             << 
 70 #include <memory>                              << 
 71                                                    68 
 72 G4bool G4ChordFinder::gVerboseCtor = false;    << 
 73 // ...........................................     69 // ..........................................................................
 74                                                    70 
 75 G4ChordFinder::G4ChordFinder(G4VIntegrationDri <<  71 G4ChordFinder::G4ChordFinder( G4MagneticField*        theMagField,
 76   : fDefaultDeltaChord(0.25 * mm), fIntgrDrive <<  72                               G4double                stepMinimum, 
                                                   >>  73                               G4MagIntegratorStepper* pItsStepper )
                                                   >>  74   : fDefaultDeltaChord( 0.25 * mm ),     // Constants 
                                                   >>  75     fDeltaChord( fDefaultDeltaChord ),   // Parameters
                                                   >>  76     fFirstFraction(0.999), fFractionLast(1.00),  fFractionNextEstimate(0.98), 
                                                   >>  77     fMultipleRadius(15.0), 
                                                   >>  78     fStatsVerbose(0),
                                                   >>  79     fDriversStepper(0),                  //  Dependent objects
                                                   >>  80     fAllocatedStepper(false),
                                                   >>  81     fEquation(0), 
                                                   >>  82     fTotalNoTrials_FNC(0), fNoCalls_FNC(0), fmaxTrials_FNC(0)  // State - stats
 77 {                                                  83 {
 78   // Simple constructor -- it does not create  <<  84   //  Construct the Chord Finder
 79   if( gVerboseCtor )                           <<  85   //  by creating in inverse order the  Driver, the Stepper and EqRhs ...
                                                   >>  86 
                                                   >>  87   G4Mag_EqRhs *pEquation = new G4Mag_UsualEqRhs(theMagField);
                                                   >>  88   fEquation = pEquation;                            
                                                   >>  89   fLastStepEstimate_Unconstrained = DBL_MAX;          // Should move q, p to
                                                   >>  90                                                      //    G4FieldTrack ??
                                                   >>  91 
                                                   >>  92   SetFractions_Last_Next( fFractionLast, fFractionNextEstimate);  
                                                   >>  93     // check the values and set the other parameters
                                                   >>  94 
                                                   >>  95   // --->>  Charge    Q = 0 
                                                   >>  96   // --->>  Momentum  P = 1       NOMINAL VALUES !!!!!!!!!!!!!!!!!!
                                                   >>  97 
                                                   >>  98   if( pItsStepper == 0 )
                                                   >>  99   { 
                                                   >> 100      pItsStepper = fDriversStepper =
                                                   >> 101          new G4ClassicalRK4(pEquation);   // The old default
                                                   >> 102          // new G4CashKarpRKF45(pEquation);
                                                   >> 103          // new G4DormandPrince745(pEquation); 
                                                   >> 104          // new G4BogackiShampine45(pEquation);
                                                   >> 105 
                                                   >> 106      fAllocatedStepper= true;
                                                   >> 107   }
                                                   >> 108   else
 80   {                                               109   {
 81     G4cout << "G4ChordFinder: Simple construct << 110      fAllocatedStepper= false; 
 82   }                                               111   }
 83                                                << 112   fIntgrDriver = new G4MagInt_Driver(stepMinimum, pItsStepper, 
 84   fDeltaChord = fDefaultDeltaChord;       // P << 113                                      pItsStepper->GetNumberOfVariables() );
 85 }                                                 114 }
 86                                                   115 
 87 // ........................................... << 
 88                                                   116 
 89 G4ChordFinder::G4ChordFinder( G4MagneticField* << 117 // ......................................................................
 90                               G4double         << 118 
 91                               G4MagIntegratorS << 119 G4ChordFinder::~G4ChordFinder()
 92                               G4int            << 
 93   : fDefaultDeltaChord(0.25 * mm)              << 
 94 {                                                 120 {
 95   // Construct the Chord Finder                << 121   delete   fEquation; // fIntgrDriver->pIntStepper->theEquation_Rhs;
 96   // by creating in inverse order the Driver,  << 122   if( fAllocatedStepper)
 97   constexpr G4int nVar6 = 6;   // Components i << 123   { 
 98                                                << 124      delete fDriversStepper; 
 99   fDeltaChord = fDefaultDeltaChord;       // P << 125   }
                                                   >> 126   delete   fIntgrDriver; 
100                                                   127 
101   G4cout << " G4ChordFinder: stepperDriverId:  << 128   if( fStatsVerbose ) { PrintStatistics(); }
                                                   >> 129 }
102                                                   130 
103   G4bool useFSALstepper     = (stepperDriverId << 131 
104   G4bool useTemplatedStepper= (stepperDriverId << 132 // ......................................................................
105   G4bool useRegularStepper  = (stepperDriverId << 133 
106   G4bool useBfieldDriver    = (stepperDriverId << 134 void   
107   G4bool useG4QSSDriver     = (stepperDriverId << 135 G4ChordFinder::SetFractions_Last_Next( G4double fractLast, G4double fractNext )
108                                                << 136 { 
109   if( stepperDriverId == kQss3DriverType)      << 137   // Use -1.0 as request for Default.
                                                   >> 138   if( fractLast == -1.0 )   fractLast = 1.0;   // 0.9;
                                                   >> 139   if( fractNext == -1.0 )   fractNext = 0.98;  // 0.9; 
                                                   >> 140 
                                                   >> 141   // fFirstFraction  = 0.999; // Orig 0.999 A safe value, range: ~ 0.95 - 0.999
                                                   >> 142   // fMultipleRadius = 15.0;  // For later use, range: ~  2 - 20 
                                                   >> 143 
                                                   >> 144   if( fStatsVerbose )
                                                   >> 145   { 
                                                   >> 146     G4cout << " ChordFnd> Trying to set fractions: "
                                                   >> 147            << " first " << fFirstFraction
                                                   >> 148            << " last " <<  fractLast
                                                   >> 149            << " next " <<  fractNext
                                                   >> 150            << " and multiple " << fMultipleRadius
                                                   >> 151            << G4endl;
                                                   >> 152   } 
                                                   >> 153 
                                                   >> 154   if( (fractLast > 0.0) && (fractLast <=1.0) ) 
110   {                                               155   {
111     stepperDriverId = kQss2DriverType;         << 156     fFractionLast= fractLast;
112     G4cout << " G4ChordFinder: QSS 3 is curren << 
113   }                                               157   }
114                                                << 158   else
115   using EquationType = G4Mag_UsualEqRhs;       << 
116                                                << 
117   using TemplatedStepperType =                 << 
118          G4TDormandPrince45<EquationType,nVar6 << 
119   const char* TemplatedStepperName =           << 
120       "G4TDormandPrince745 (templated Dormand- << 
121                                                << 
122   using RegularStepperType =                   << 
123          G4DormandPrince745; // 5th order embe << 
124          // G4ClassicalRK4;        // The old  << 
125          // G4CashKarpRKF45;       // First em << 
126          // G4BogackiShampine45;   // High eff << 
127          // G4NystromRK4;          // Nystrom  << 
128          // G4RK547FEq1;  // or 2 or 3         << 
129   const char* RegularStepperName =             << 
130       "G4DormandPrince745 (aka DOPRI5): 5th/4t << 
131       // "BogackiShampine 45 (Embedded 5th/4th << 
132       // "Nystrom stepper 4th order";          << 
133                                                << 
134   using NewFsalStepperType = G4DormandPrince74 << 
135                                                << 
136   const char* NewFSALStepperName =             << 
137       "G4RK574FEq1> FSAL 4th/5th order 7-stage << 
138                                                << 
139 #ifdef G4DEBUG_FIELD                           << 
140   static G4bool verboseDebug = true;           << 
141   if( verboseDebug )                           << 
142   {                                               159   {
143      G4cout << "G4ChordFinder 2nd Constructor  << 160     G4cerr << "G4ChordFinder::SetFractions_Last_Next: Invalid "
144      G4cout << " Arguments: " << G4endl        << 161            << " fraction Last = " << fractLast
145             << " - min step = " << stepMinimum << 162            << " must be  0 <  fractionLast <= 1 " << G4endl;
146             << " - stepper ptr provided : "    << 
147             << ( pItsStepper==nullptr ? " no   << 
148      if( pItsStepper==nullptr )                << 
149         G4cout << " - stepper/driver Id = " << << 
150                << "  useFSAL = " << useFSALste << 
151                << "  , useTemplated = " << use << 
152                << "  , useRegular = " << useRe << 
153                << "  , useFSAL = " << useFSALs << 
154                << G4endl;                      << 
155   }                                               163   }
156 #endif                                         << 164   if( (fractNext > 0.0) && (fractNext <1.0) )
157                                                << 165   {
158   // useHigherStepper = forceHigherEffiencySte << 166     fFractionNextEstimate = fractNext;
                                                   >> 167   }
                                                   >> 168   else
                                                   >> 169   {
                                                   >> 170     G4cerr << "G4ChordFinder:: SetFractions_Last_Next: Invalid "
                                                   >> 171            << " fraction Next = " << fractNext
                                                   >> 172            << " must be  0 <  fractionNext < 1 " << G4endl;
                                                   >> 173   }
                                                   >> 174 }
159                                                   175 
160   auto  pEquation = new G4Mag_UsualEqRhs(theMa << 
161   fEquation = pEquation;                       << 
162                                                   176 
163   // G4MagIntegratorStepper* regularStepper =  << 177 // ......................................................................
164   // G4VFSALIntegrationStepper* fsalStepper =  << 
165   // G4MagIntegratorStepper* oldFSALStepper =  << 
166                                                   178 
167   G4bool errorInStepperCreation = false;       << 179 G4double 
                                                   >> 180 G4ChordFinder::AdvanceChordLimited( G4FieldTrack& yCurrent,
                                                   >> 181                                     G4double      stepMax,
                                                   >> 182                                     G4double      epsStep,
                                                   >> 183                                     const G4ThreeVector latestSafetyOrigin,
                                                   >> 184                                     G4double       latestSafetyRadius )
                                                   >> 185 {
                                                   >> 186   G4double stepPossible;
                                                   >> 187   G4double dyErr;
                                                   >> 188   G4FieldTrack yEnd( yCurrent);
                                                   >> 189   G4double  startCurveLen= yCurrent.GetCurveLength();
                                                   >> 190   G4double nextStep;
                                                   >> 191   //            *************
                                                   >> 192   stepPossible= FindNextChord(yCurrent, stepMax, yEnd, dyErr, epsStep,
                                                   >> 193                               &nextStep, latestSafetyOrigin, latestSafetyRadius
                                                   >> 194                              );
                                                   >> 195   //            *************
168                                                   196 
169   std::ostringstream message;  // In case of f << 197   G4bool good_advance;
170                                                   198 
171   if( pItsStepper != nullptr )                 << 199   if ( dyErr < epsStep * stepPossible )
172   {                                               200   {
173      if( gVerboseCtor )                        << 201      // Accept this accuracy.
174      {                                         << 
175        G4cout << " G4ChordFinder: Creating G4I << 
176               << " stepMinimum = " << stepMini << 
177               << " numVar= " << pItsStepper->G << 
178      }                                         << 
179                                                   202 
180      // Stepper type is not known - so must us << 203      yCurrent = yEnd;
181       if(pItsStepper->isQSS())                 << 204      good_advance = true; 
182       {                                        << 
183          // fIntgrDriver = pItsStepper->build_ << 
184          G4Exception("G4ChordFinder::G4ChordFi << 
185                       "GeomField1001", FatalEx << 
186                       "Cannot provide  QSS ste << 
187       }                                        << 
188       else                                     << 
189       {                                        << 
190          fIntgrDriver = new G4IntegrationDrive << 
191                                   pItsStepper, << 
192          // Stepper type is not known - so mus << 
193          // Non-interpolating driver used by d << 
194          // WAS:  fIntgrDriver = pItsStepper-> << 
195       }                                        << 
196      // -- Older:                              << 
197      // G4cout << " G4ChordFinder: Creating G4 << 
198      // Type is not known - so must use old cl << 
199      // fIntgrDriver = new G4MagInt_Driver( st << 
200      //                                 pItsSt << 
201   }                                               205   }
202   else if ( useTemplatedStepper )              << 206   else
203   {                                            << 207   {  
204      if( gVerboseCtor )                        << 208      // Advance more accurately to "end of chord"
205      {                                         << 209      //                           ***************
206         G4cout << " G4ChordFinder: Creating Te << 210      good_advance = fIntgrDriver->AccurateAdvance(yCurrent, stepPossible,
207                << TemplatedStepperName << G4en << 211                                                   epsStep, nextStep);
208      }                                         << 212      if ( ! good_advance )
209      // RegularStepperType* regularStepper = n << 213      { 
210      auto templatedStepper = new TemplatedStep << 214        // In this case the driver could not do the full distance
211      //                    *** *************** << 215        stepPossible= yCurrent.GetCurveLength()-startCurveLen;
212      //                                        << 
213      // Alternative - for G4NystromRK4:        << 
214      // = new G4NystromRK4(pEquation, 0.1*mm ) << 
215      fRegularStepperOwned = templatedStepper;  << 
216      if( templatedStepper == nullptr )         << 
217      {                                         << 
218         message << "Templated Stepper instanti << 
219         message << "G4ChordFinder: Attempted t << 
220                 << TemplatedStepperName << " t << 
221         errorInStepperCreation = true;         << 
222      }                                         << 
223      else                                      << 
224      {                                         << 
225         fIntgrDriver = new G4IntegrationDriver << 
226            stepMinimum, templatedStepper, nVar << 
227         if( gVerboseCtor )                     << 
228         {                                      << 
229            G4cout << " G4ChordFinder: Using G4 << 
230         }                                      << 
231      }                                            216      }
232                                                << 
233   }                                               217   }
234   else if ( useRegularStepper   )  // Plain st << 218   return stepPossible;
235   {                                            << 219 }
236      auto regularStepper = new RegularStepperT << 
237      //                    *** *************** << 
238      fRegularStepperOwned = regularStepper;    << 
239                                                   220 
240      if( gVerboseCtor )                        << 221 
241      {                                         << 222 // ............................................................................
242         G4cout << " G4ChordFinder: Creating Dr << 223 
243      }                                         << 224 G4double
                                                   >> 225 G4ChordFinder::FindNextChord( const  G4FieldTrack& yStart,
                                                   >> 226                                      G4double     stepMax,
                                                   >> 227                                      G4FieldTrack&   yEnd, // Endpoint
                                                   >> 228                                      G4double&   dyErrPos, // Error of endpoint
                                                   >> 229                                      G4double    epsStep,
                                                   >> 230                                      G4double*  pStepForAccuracy, 
                                                   >> 231                               const  G4ThreeVector, //  latestSafetyOrigin,
                                                   >> 232                                      G4double       //  latestSafetyRadius 
                                                   >> 233                                         )
                                                   >> 234 {
                                                   >> 235   // Returns Length of Step taken
                                                   >> 236 
                                                   >> 237   G4FieldTrack yCurrent=  yStart;  
                                                   >> 238   G4double    stepTrial, stepForAccuracy;
                                                   >> 239   G4double    dydx[G4FieldTrack::ncompSVEC]; 
                                                   >> 240 
                                                   >> 241   //  1.)  Try to "leap" to end of interval
                                                   >> 242   //  2.)  Evaluate if resulting chord gives d_chord that is good enough.
                                                   >> 243   // 2a.)  If d_chord is not good enough, find one that is.
                                                   >> 244   
                                                   >> 245   G4bool    validEndPoint= false;
                                                   >> 246   G4double  dChordStep, lastStepLength; //  stepOfLastGoodChord;
                                                   >> 247 
                                                   >> 248   fIntgrDriver-> GetDerivatives( yCurrent, dydx );
                                                   >> 249 
                                                   >> 250   unsigned int        noTrials=0;
                                                   >> 251   const unsigned int  maxTrials= 75; // Avoid endless loop for bad convergence 
                                                   >> 252 
                                                   >> 253   const G4double safetyFactor= fFirstFraction; //  0.975 or 0.99 ? was 0.999
                                                   >> 254 
                                                   >> 255   stepTrial = std::min( stepMax, safetyFactor*fLastStepEstimate_Unconstrained );
                                                   >> 256 
                                                   >> 257   G4double newStepEst_Uncons= 0.0; 
                                                   >> 258   G4double stepForChord;
                                                   >> 259   do
                                                   >> 260   { 
                                                   >> 261      yCurrent = yStart;    // Always start from initial point  
                                                   >> 262      //            ************
                                                   >> 263      fIntgrDriver->QuickAdvance( yCurrent, dydx, stepTrial, 
                                                   >> 264                                  dChordStep, dyErrPos);
                                                   >> 265      //            ************
244                                                   266      
245      if( regularStepper == nullptr )           << 267      //  We check whether the criterion is met here.
246      {                                         << 268      validEndPoint = AcceptableMissDist(dChordStep);
247         message << "Regular Stepper instantiat << 269 
248         message << "G4ChordFinder: Attempted t << 270      lastStepLength = stepTrial; 
249                 << RegularStepperName << " typ << 271 
250         errorInStepperCreation = true;         << 272      // This method estimates to step size for a good chord.
251      }                                         << 273      stepForChord = NewStep(stepTrial, dChordStep, newStepEst_Uncons );
252      else                                      << 274 
                                                   >> 275      if( ! validEndPoint )
253      {                                            276      {
254         auto dp5= dynamic_cast<G4DormandPrince << 277         if( stepTrial<=0.0 )
255         if( dp5 != nullptr )                   << 
256         {                                         278         {
257            fIntgrDriver = new G4InterpolationD << 279           stepTrial = stepForChord;
258                                   stepMinimum, << 280         }
259            if( gVerboseCtor )                  << 281         else if (stepForChord <= stepTrial)
260            {                                   << 282         {
261               G4cout << " Using InterpolationD << 283           // Reduce by a fraction, possibly up to 20% 
262            }                                   << 284           stepTrial = std::min( stepForChord, fFractionLast * stepTrial);
263         }                                         285         }
264         else                                      286         else
265         {                                         287         {
266            fIntgrDriver = new G4IntegrationDri << 288           stepTrial *= 0.1;
267                                   stepMinimum, << 
268            if( gVerboseCtor )                  << 
269            {                                   << 
270               G4cout << " Using IntegrationDri << 
271            }                                   << 
272         }                                         289         }
273      }                                            290      }
                                                   >> 291      noTrials++; 
274   }                                               292   }
275   else if ( useBfieldDriver )                  << 293   while( (! validEndPoint) && (noTrials < maxTrials) );
                                                   >> 294   // Loop checking, 07.10.2016, J. Apostolakis
                                                   >> 295 
                                                   >> 296   if( noTrials >= maxTrials )
276   {                                               297   {
277      auto regularStepper = new G4DormandPrince << 298       std::ostringstream message;
278      //                    *** *************** << 299       message << "Exceeded maximum number of trials= " << maxTrials << G4endl
279      //                                        << 300               << "Current sagita dist= " << dChordStep << G4endl
280      fRegularStepperOwned = regularStepper;    << 301               << "Step sizes (actual and proposed): " << G4endl
281                                                << 302               << "Last trial =         " << lastStepLength  << G4endl
282      {                                         << 303               << "Next trial =         " << stepTrial  << G4endl
283         using SmallStepDriver = G4Interpolatio << 304               << "Proposed for chord = " << stepForChord  << G4endl              
284         using LargeStepDriver = G4IntegrationD << 305               ;
285                                                << 306       G4Exception("G4ChordFinder::FindNextChord()", "GeomField0003",
286         fLongStepper = std::make_unique<G4Heli << 307                   JustWarning, message);
287                                                << 
288         fIntgrDriver = new G4BFieldIntegration << 
289           std::make_unique<SmallStepDriver>(st << 
290               regularStepper, regularStepper-> << 
291           std::make_unique<LargeStepDriver>(st << 
292               fLongStepper.get(), regularStepp << 
293                                                << 
294         if( fIntgrDriver == nullptr)           << 
295         {                                      << 
296            message << "Using G4BFieldIntegrati << 
297                    << RegularStepperName << "  << 
298            message << "Driver instantiation FA << 
299            G4Exception("G4ChordFinder::G4Chord << 
300                        "GeomField1001", JustWa << 
301         }                                      << 
302      }                                         << 
303   }                                               308   }
304   else if( useG4QSSDriver )                    << 309 
                                                   >> 310   if( newStepEst_Uncons > 0.0  )
305   {                                               311   {
306      if( stepperDriverId == kQss2DriverType )  << 312      fLastStepEstimate_Unconstrained= newStepEst_Uncons;
                                                   >> 313   }
                                                   >> 314 
                                                   >> 315   AccumulateStatistics( noTrials );
                                                   >> 316 
                                                   >> 317   if( pStepForAccuracy )
                                                   >> 318   { 
                                                   >> 319      // Calculate the step size required for accuracy, if it is needed
                                                   >> 320      //
                                                   >> 321      G4double dyErr_relative = dyErrPos/(epsStep*lastStepLength);
                                                   >> 322      if( dyErr_relative > 1.0 )
307      {                                            323      {
308        auto qssStepper2 = G4QSSDriverCreator:: << 324         stepForAccuracy = fIntgrDriver->ComputeNewStepSize( dyErr_relative,
309        if( gVerboseCtor )                      << 325                                                             lastStepLength );
310        {                                       << 
311          G4cout << "-- Created QSS-2 stepper"  << 
312        }                                       << 
313        fIntgrDriver = G4QSSDriverCreator::Crea << 
314      }                                            326      }
315      else                                         327      else
316      {                                            328      {
317        auto qssStepper3 = G4QSSDriverCreator:: << 329         stepForAccuracy = 0.0;   // Convention to show step was ok 
318        if( gVerboseCtor )                      << 
319        {                                       << 
320          G4cout << "-- Created QSS-3 stepper"  << 
321        }                                       << 
322        fIntgrDriver = G4QSSDriverCreator::Crea << 
323      }                                         << 
324      if( gVerboseCtor )                        << 
325      {                                         << 
326        G4cout << "-- G4ChordFinder: Using QSS  << 
327      }                                            330      }
                                                   >> 331      *pStepForAccuracy = stepForAccuracy;
                                                   >> 332   }
                                                   >> 333 
                                                   >> 334 #ifdef  TEST_CHORD_PRINT
                                                   >> 335   static int dbg=0;
                                                   >> 336   if( dbg )
                                                   >> 337   {
                                                   >> 338     G4cout << "ChordF/FindNextChord:  NoTrials= " << noTrials 
                                                   >> 339            << " StepForGoodChord=" << std::setw(10) << stepTrial << G4endl;
                                                   >> 340   }
                                                   >> 341 #endif
                                                   >> 342   yEnd=  yCurrent;  
                                                   >> 343   return stepTrial; 
                                                   >> 344 }
                                                   >> 345 
                                                   >> 346 
                                                   >> 347 // ...........................................................................
                                                   >> 348 
                                                   >> 349 G4double G4ChordFinder::NewStep(G4double  stepTrialOld, 
                                                   >> 350                                 G4double  dChordStep, // Curr. dchord achieved
                                                   >> 351                                 G4double& stepEstimate_Unconstrained )  
                                                   >> 352 {
                                                   >> 353   // Is called to estimate the next step size, even for successful steps,
                                                   >> 354   // in order to predict an accurate 'chord-sensitive' first step
                                                   >> 355   // which is likely to assist in more performant 'stepping'.
                                                   >> 356 
                                                   >> 357   G4double stepTrial;
                                                   >> 358 
                                                   >> 359 #if 1
                                                   >> 360 
                                                   >> 361   if (dChordStep > 0.0)
                                                   >> 362   {
                                                   >> 363     stepEstimate_Unconstrained =
                                                   >> 364                  stepTrialOld*std::sqrt( fDeltaChord / dChordStep );
                                                   >> 365     stepTrial =  fFractionNextEstimate * stepEstimate_Unconstrained;
328   }                                               366   }
329   else                                            367   else
330   {                                               368   {
331      auto fsalStepper=  new NewFsalStepperType << 369     // Should not update the Unconstrained Step estimate: incorrect!
332      //                 *** ****************** << 370     stepTrial =  stepTrialOld * 2.; 
333      fNewFSALStepperOwned = fsalStepper;       << 371   }
334                                                   372 
335      if( fsalStepper == nullptr )              << 373   if( stepTrial <= 0.001 * stepTrialOld)
                                                   >> 374   {
                                                   >> 375      if ( dChordStep > 1000.0 * fDeltaChord )
336      {                                            376      {
337         message << "Stepper instantiation FAIL << 377         stepTrial= stepTrialOld * 0.03;   
338         message << "Attempted to instantiate " << 
339                 << NewFSALStepperName << " typ << 
340         G4Exception("G4ChordFinder::G4ChordFin << 
341                     "GeomField1001", JustWarni << 
342         errorInStepperCreation = true;         << 
343      }                                            378      }
344      else                                         379      else
345      {                                            380      {
346         fIntgrDriver = new                     << 381         if ( dChordStep > 100. * fDeltaChord )
347            G4FSALIntegrationDriver<NewFsalStep << 382         {
348                                           fsal << 383           stepTrial= stepTrialOld * 0.1;   
349            //  ====  Create the driver which k << 384         }
350                                                << 385         else   // Try halving the length until dChordStep OK
351         if( fIntgrDriver == nullptr )          << 
352         {                                         386         {
353            message << "Using G4FSALIntegration << 387           stepTrial= stepTrialOld * 0.5;   
354                    << NewFSALStepperName << G4 << 
355            message << "Integration Driver inst << 
356            G4Exception("G4ChordFinder::G4Chord << 
357                        "GeomField1001", JustWa << 
358         }                                         388         }
359      }                                            389      }
360   }                                               390   }
                                                   >> 391   else if (stepTrial > 1000.0 * stepTrialOld)
                                                   >> 392   {
                                                   >> 393      stepTrial= 1000.0 * stepTrialOld;
                                                   >> 394   }
361                                                   395 
362   // -- Main work is now done                  << 396   if( stepTrial == 0.0 )
363                                                << 
364   //    Now check that no error occured, and r << 
365                                                << 
366   // To test failure to create driver          << 
367   // delete fIntgrDriver;                      << 
368   // fIntgrDriver = nullptr;                   << 
369                                                << 
370   // Detect and report Error conditions        << 
371   //                                           << 
372   if( errorInStepperCreation || (fIntgrDriver  << 
373   {                                               397   {
374      std::ostringstream errmsg;                << 398      stepTrial= 0.000001;
375                                                << 399   }
376      if( errorInStepperCreation )              << 400 
                                                   >> 401 #else
                                                   >> 402 
                                                   >> 403   if ( dChordStep > 1000. * fDeltaChord )
                                                   >> 404   {
                                                   >> 405         stepTrial= stepTrialOld * 0.03;   
                                                   >> 406   }
                                                   >> 407   else
                                                   >> 408   {
                                                   >> 409      if ( dChordStep > 100. * fDeltaChord )
377      {                                            410      {
378         errmsg  << "ERROR> Failure to create S << 411         stepTrial= stepTrialOld * 0.1;   
379                 << "       ------------------- << 
380      }                                            412      }
381      if (fIntgrDriver == nullptr )             << 413      else  // Keep halving the length until dChordStep OK
382      {                                            414      {
383         errmsg  << "ERROR> Failure to create I << 415         stepTrial= stepTrialOld * 0.5;   
384                 << G4endl                      << 
385                 << "       ------------------- << 
386                 << G4endl;                     << 
387      }                                            416      }
388      const std::string BoolName[2]= { "False", << 
389      errmsg << "  Configuration:  (constructor << 
390             << "    provided Stepper = " << pI << 
391             << " stepper/driver Id = " << step << 
392             << "   useTemplated = " << BoolNam << 
393             << "   useRegular = " << BoolName[ << 
394             << "   useFSAL = " << BoolName[use << 
395             << "   using combo BField Driver = << 
396                    BoolName[ ! (useFSALstepper << 
397                                || useRegularSt << 
398             << G4endl;                         << 
399      errmsg << message.str();                  << 
400      errmsg << "Aborting.";                    << 
401      G4Exception("G4ChordFinder::G4ChordFinder << 
402                  "GeomField0003", FatalExcepti << 
403   }                                               417   }
404                                                   418 
405   assert(    ( pItsStepper != nullptr )        << 419 #endif 
406           || ( fRegularStepperOwned != nullptr << 
407           || ( fNewFSALStepperOwned != nullptr << 
408           || useG4QSSDriver                    << 
409      );                                        << 
410   assert( fIntgrDriver != nullptr );           << 
411 }                                              << 
412                                                   420 
413 // ........................................... << 421   // A more sophisticated chord-finder could figure out a better
                                                   >> 422   // stepTrial, from dChordStep and the required d_geometry
                                                   >> 423   //   e.g.
                                                   >> 424   //      Calculate R, r_helix (eg at orig point)
                                                   >> 425   //      if( stepTrial < 2 pi  R )
                                                   >> 426   //          stepTrial = R arc_cos( 1 - fDeltaChord / r_helix )
                                                   >> 427   //      else    
                                                   >> 428   //          ??
414                                                   429 
415 G4ChordFinder::~G4ChordFinder()                << 430   return stepTrial;
416 {                                              << 
417   delete fEquation;                            << 
418   delete fRegularStepperOwned;                 << 
419   delete fNewFSALStepperOwned;                 << 
420   delete fCachedField;                         << 
421   delete fIntgrDriver;                         << 
422 }                                                 431 }
423                                                   432 
                                                   >> 433 
424 // ...........................................    434 // ...........................................................................
425                                                   435 
426 G4FieldTrack                                      436 G4FieldTrack
427 G4ChordFinder::ApproxCurvePointS( const G4Fiel    437 G4ChordFinder::ApproxCurvePointS( const G4FieldTrack&  CurveA_PointVelocity, 
428                                   const G4Fiel    438                                   const G4FieldTrack&  CurveB_PointVelocity, 
429                                   const G4Fiel    439                                   const G4FieldTrack&  ApproxCurveV,
430                                   const G4Thre    440                                   const G4ThreeVector& CurrentE_Point,
431                                   const G4Thre    441                                   const G4ThreeVector& CurrentF_Point,
432                                   const G4Thre    442                                   const G4ThreeVector& PointG,
433                                         G4bool << 443                                        G4bool first, G4double eps_step)
434 {                                                 444 {
435   // ApproxCurvePointS is 2nd implementation o    445   // ApproxCurvePointS is 2nd implementation of ApproxCurvePoint.
436   // Use Brent Algorithm (or InvParabolic) whe    446   // Use Brent Algorithm (or InvParabolic) when possible.
437   // Given a starting curve point A (CurveA_Po    447   // Given a starting curve point A (CurveA_PointVelocity), curve point B
438   // (CurveB_PointVelocity), a point E which i    448   // (CurveB_PointVelocity), a point E which is (generally) not on the curve
439   // and  a point F which is on the curve (fir    449   // and  a point F which is on the curve (first approximation), find new
440   // point S on the curve closer to point E.      450   // point S on the curve closer to point E. 
441   // While advancing towards S utilise 'eps_st    451   // While advancing towards S utilise 'eps_step' as a measure of the
442   // relative accuracy of each Step.              452   // relative accuracy of each Step.
443                                                   453 
444   G4FieldTrack EndPoint(CurveA_PointVelocity);    454   G4FieldTrack EndPoint(CurveA_PointVelocity);
445   if(!first) { EndPoint = ApproxCurveV; }      << 455   if(!first){EndPoint= ApproxCurveV;}
446                                                   456 
447   G4ThreeVector Point_A,Point_B;                  457   G4ThreeVector Point_A,Point_B;
448   Point_A=CurveA_PointVelocity.GetPosition();     458   Point_A=CurveA_PointVelocity.GetPosition();
449   Point_B=CurveB_PointVelocity.GetPosition();     459   Point_B=CurveB_PointVelocity.GetPosition();
450                                                   460 
451   G4double xa,xb,xc,ya,yb,yc;                     461   G4double xa,xb,xc,ya,yb,yc;
452                                                   462  
453   // InverseParabolic. AF Intersects (First Pa    463   // InverseParabolic. AF Intersects (First Part of Curve) 
454                                                   464 
455   if(first)                                       465   if(first)
456   {                                               466   {
457     xa=0.;                                        467     xa=0.;
458     ya=(PointG-Point_A).mag();                    468     ya=(PointG-Point_A).mag();
459     xb=(Point_A-CurrentF_Point).mag();            469     xb=(Point_A-CurrentF_Point).mag();
460     yb=-(PointG-CurrentF_Point).mag();            470     yb=-(PointG-CurrentF_Point).mag();
461     xc=(Point_A-Point_B).mag();                   471     xc=(Point_A-Point_B).mag();
462     yc=-(CurrentE_Point-Point_B).mag();           472     yc=-(CurrentE_Point-Point_B).mag();
463   }                                               473   }    
464   else                                            474   else
465   {                                               475   {
466     xa=0.;                                        476     xa=0.;
467     ya=(Point_A-CurrentE_Point).mag();            477     ya=(Point_A-CurrentE_Point).mag();
468     xb=(Point_A-CurrentF_Point).mag();            478     xb=(Point_A-CurrentF_Point).mag();
469     yb=(PointG-CurrentF_Point).mag();             479     yb=(PointG-CurrentF_Point).mag();
470     xc=(Point_A-Point_B).mag();                   480     xc=(Point_A-Point_B).mag();
471     yc=-(Point_B-PointG).mag();                   481     yc=-(Point_B-PointG).mag();
472     if(xb==0.)                                    482     if(xb==0.)
473     {                                             483     {
474       EndPoint = ApproxCurvePointV(CurveA_Poin << 484       EndPoint=
475                                    CurrentE_Po << 485       ApproxCurvePointV(CurveA_PointVelocity, CurveB_PointVelocity,
                                                   >> 486                         CurrentE_Point, eps_step);
476       return EndPoint;                            487       return EndPoint;
477     }                                             488     }
478   }                                               489   }
479                                                   490 
480   const G4double tolerance = 1.e-12;           << 491   const G4double tolerance= 1.e-12;
481   if(std::abs(ya)<=tolerance||std::abs(yc)<=to    492   if(std::abs(ya)<=tolerance||std::abs(yc)<=tolerance)
482   {                                               493   {
483     ; // What to do for the moment: return the    494     ; // What to do for the moment: return the same point as at start
484       // then PropagatorInField will take care    495       // then PropagatorInField will take care
485   }                                               496   }
486   else                                            497   else
487   {                                               498   {
488     G4double test_step = InvParabolic(xa,ya,xb    499     G4double test_step = InvParabolic(xa,ya,xb,yb,xc,yc);
489     G4double curve;                               500     G4double curve;
490     if(first)                                     501     if(first)
491     {                                             502     {
492       curve=std::abs(EndPoint.GetCurveLength()    503       curve=std::abs(EndPoint.GetCurveLength()
493                     -ApproxCurveV.GetCurveLeng    504                     -ApproxCurveV.GetCurveLength());
494     }                                             505     }
495     else                                          506     else
496     {                                             507     {
497       test_step = test_step - xb;              << 508       test_step=(test_step-xb);
498       curve=std::abs(EndPoint.GetCurveLength()    509       curve=std::abs(EndPoint.GetCurveLength()
499                     -CurveB_PointVelocity.GetC    510                     -CurveB_PointVelocity.GetCurveLength());
500       xb = (CurrentF_Point-Point_B).mag();     << 511       xb=(CurrentF_Point-Point_B).mag();
501     }                                             512     }
502                                                   513       
503     if(test_step<=0)    { test_step=0.1*xb; }     514     if(test_step<=0)    { test_step=0.1*xb; }
504     if(test_step>=xb)   { test_step=0.5*xb; }     515     if(test_step>=xb)   { test_step=0.5*xb; }
505     if(test_step>=curve){ test_step=0.5*curve;    516     if(test_step>=curve){ test_step=0.5*curve; } 
506                                                   517 
507     if(curve*(1.+eps_step)<xb) // Similar to R    518     if(curve*(1.+eps_step)<xb) // Similar to ReEstimate Step from
508     {                          // G4VIntersect    519     {                          // G4VIntersectionLocator
509       test_step=0.5*curve;                        520       test_step=0.5*curve;
510     }                                             521     }
511                                                   522 
512     fIntgrDriver->AccurateAdvance(EndPoint,tes    523     fIntgrDriver->AccurateAdvance(EndPoint,test_step, eps_step);
513                                                   524       
514 #ifdef G4DEBUG_FIELD                              525 #ifdef G4DEBUG_FIELD
515     // Printing Brent and Linear Approximation    526     // Printing Brent and Linear Approximation
516     //                                            527     //
517     G4cout << "G4ChordFinder::ApproxCurvePoint    528     G4cout << "G4ChordFinder::ApproxCurvePointS() - test-step ShF = "
518            << test_step << "  EndPoint = " <<     529            << test_step << "  EndPoint = " << EndPoint << G4endl;
519                                                   530 
520     //  Test Track                                531     //  Test Track
521     //                                            532     //
522     G4FieldTrack TestTrack( CurveA_PointVeloci    533     G4FieldTrack TestTrack( CurveA_PointVelocity);
523     TestTrack = ApproxCurvePointV( CurveA_Poin    534     TestTrack = ApproxCurvePointV( CurveA_PointVelocity, 
524                                    CurveB_Poin    535                                    CurveB_PointVelocity, 
525                                    CurrentE_Po    536                                    CurrentE_Point, eps_step );
526     G4cout.precision(14);                         537     G4cout.precision(14);
527     G4cout << "G4ChordFinder::BrentApprox = "     538     G4cout << "G4ChordFinder::BrentApprox = " << EndPoint  << G4endl;
528     G4cout << "G4ChordFinder::LinearApprox= "     539     G4cout << "G4ChordFinder::LinearApprox= " << TestTrack << G4endl; 
529 #endif                                            540 #endif
530   }                                               541   }
531   return EndPoint;                                542   return EndPoint;
532 }                                                 543 }
533                                                   544 
534                                                   545 
535 // ...........................................    546 // ...........................................................................
536                                                   547 
537 G4FieldTrack G4ChordFinder::                      548 G4FieldTrack G4ChordFinder::
538 ApproxCurvePointV( const G4FieldTrack& CurveA_    549 ApproxCurvePointV( const G4FieldTrack& CurveA_PointVelocity, 
539                    const G4FieldTrack& CurveB_    550                    const G4FieldTrack& CurveB_PointVelocity, 
540                    const G4ThreeVector& Curren    551                    const G4ThreeVector& CurrentE_Point,
541                          G4double eps_step)       552                          G4double eps_step)
542 {                                                 553 {
543   // If r=|AE|/|AB|, and s=true path lenght (A    554   // If r=|AE|/|AB|, and s=true path lenght (AB)
544   // return the point that is r*s along the cu    555   // return the point that is r*s along the curve!
545                                                   556  
546   G4FieldTrack   Current_PointVelocity = Curve    557   G4FieldTrack   Current_PointVelocity = CurveA_PointVelocity; 
547                                                   558 
548   G4ThreeVector  CurveA_Point= CurveA_PointVel    559   G4ThreeVector  CurveA_Point= CurveA_PointVelocity.GetPosition();
549   G4ThreeVector  CurveB_Point= CurveB_PointVel    560   G4ThreeVector  CurveB_Point= CurveB_PointVelocity.GetPosition();
550                                                   561 
551   G4ThreeVector  ChordAB_Vector= CurveB_Point     562   G4ThreeVector  ChordAB_Vector= CurveB_Point   - CurveA_Point;
552   G4ThreeVector  ChordAE_Vector= CurrentE_Poin    563   G4ThreeVector  ChordAE_Vector= CurrentE_Point - CurveA_Point;
553                                                   564 
554   G4double       ABdist= ChordAB_Vector.mag();    565   G4double       ABdist= ChordAB_Vector.mag();
555   G4double  curve_length;  //  A curve length     566   G4double  curve_length;  //  A curve length  of AB
556   G4double  AE_fraction;                          567   G4double  AE_fraction; 
557                                                   568   
558   curve_length= CurveB_PointVelocity.GetCurveL    569   curve_length= CurveB_PointVelocity.GetCurveLength()
559               - CurveA_PointVelocity.GetCurveL    570               - CurveA_PointVelocity.GetCurveLength();  
560                                                   571  
561   G4double integrationInaccuracyLimit= std::ma << 572   G4double  integrationInaccuracyLimit= std::max( perMillion, 0.5*eps_step ); 
562   if( curve_length < ABdist * (1. - integratio    573   if( curve_length < ABdist * (1. - integrationInaccuracyLimit) )
563   {                                               574   { 
564 #ifdef G4DEBUG_FIELD                              575 #ifdef G4DEBUG_FIELD
565     G4cerr << " Warning in G4ChordFinder::Appr    576     G4cerr << " Warning in G4ChordFinder::ApproxCurvePoint: "
566            << G4endl                              577            << G4endl
567            << " The two points are further apa    578            << " The two points are further apart than the curve length "
568            << G4endl                              579            << G4endl
569            << " Dist = "         << ABdist        580            << " Dist = "         << ABdist
570            << " curve length = " << curve_leng    581            << " curve length = " << curve_length 
571            << " relativeDiff = " << (curve_len    582            << " relativeDiff = " << (curve_length-ABdist)/ABdist 
572            << G4endl;                             583            << G4endl;
573     if( curve_length < ABdist * (1. - 10*eps_s    584     if( curve_length < ABdist * (1. - 10*eps_step) )
574     {                                             585     {
575       std::ostringstream message;                 586       std::ostringstream message;
576       message << "Unphysical curve length." <<    587       message << "Unphysical curve length." << G4endl
577               << "The size of the above differ    588               << "The size of the above difference exceeds allowed limits."
578               << G4endl                           589               << G4endl
579               << "Aborting.";                     590               << "Aborting.";
580       G4Exception("G4ChordFinder::ApproxCurveP    591       G4Exception("G4ChordFinder::ApproxCurvePointV()", "GeomField0003",
581                   FatalException, message);       592                   FatalException, message);
582     }                                             593     }
583 #endif                                            594 #endif
584     // Take default corrective action: adjust     595     // Take default corrective action: adjust the maximum curve length. 
585     // NOTE: this case only happens for relati    596     // NOTE: this case only happens for relatively straight paths.
586     // curve_length = ABdist;                     597     // curve_length = ABdist; 
587   }                                               598   }
588                                                   599 
589   G4double new_st_length;                      << 600   G4double  new_st_length; 
590                                                   601 
591   if ( ABdist > 0.0 )                             602   if ( ABdist > 0.0 )
592   {                                               603   {
593      AE_fraction = ChordAE_Vector.mag() / ABdi    604      AE_fraction = ChordAE_Vector.mag() / ABdist;
594   }                                               605   }
595   else                                            606   else
596   {                                               607   {
597      AE_fraction = 0.5;                           608      AE_fraction = 0.5;                         // Guess .. ?; 
598 #ifdef G4DEBUG_FIELD                              609 #ifdef G4DEBUG_FIELD
599      G4cout << "Warning in G4ChordFinder::Appr    610      G4cout << "Warning in G4ChordFinder::ApproxCurvePointV():"
600             << " A and B are the same point!"     611             << " A and B are the same point!" << G4endl
601             << " Chord AB length = " << ChordA    612             << " Chord AB length = " << ChordAE_Vector.mag() << G4endl
602             << G4endl;                            613             << G4endl;
603 #endif                                            614 #endif
604   }                                               615   }
605                                                   616   
606   if( (AE_fraction> 1.0 + perMillion) || (AE_f    617   if( (AE_fraction> 1.0 + perMillion) || (AE_fraction< 0.) )
607   {                                               618   {
608 #ifdef G4DEBUG_FIELD                              619 #ifdef G4DEBUG_FIELD
609     G4cerr << " G4ChordFinder::ApproxCurvePoin    620     G4cerr << " G4ChordFinder::ApproxCurvePointV() - Warning:"
610            << " Anomalous condition:AE > AB or    621            << " Anomalous condition:AE > AB or AE/AB <= 0 " << G4endl
611            << "   AE_fraction = " <<  AE_fract    622            << "   AE_fraction = " <<  AE_fraction << G4endl
612            << "   Chord AE length = " << Chord    623            << "   Chord AE length = " << ChordAE_Vector.mag() << G4endl
613            << "   Chord AB length = " << ABdis    624            << "   Chord AB length = " << ABdist << G4endl << G4endl;
614     G4cerr << " OK if this condition occurs af    625     G4cerr << " OK if this condition occurs after a recalculation of 'B'"
615            << G4endl << " Otherwise it is an e    626            << G4endl << " Otherwise it is an error. " << G4endl ; 
616 #endif                                            627 #endif
617      // This course can now result if B has be    628      // This course can now result if B has been re-evaluated, 
618      // without E being recomputed (1 July 99)    629      // without E being recomputed (1 July 99).
619      // In this case this is not a "real error    630      // In this case this is not a "real error" - but it is undesired
620      // and we cope with it by a default corre    631      // and we cope with it by a default corrective action ...
621      //                                           632      //
622      AE_fraction = 0.5;                           633      AE_fraction = 0.5;                         // Default value
623   }                                               634   }
624                                                   635 
625   new_st_length = AE_fraction * curve_length;  << 636   new_st_length= AE_fraction * curve_length; 
626                                                   637 
627   if ( AE_fraction > 0.0 )                        638   if ( AE_fraction > 0.0 )
628   {                                               639   { 
629      fIntgrDriver->AccurateAdvance(Current_Poi    640      fIntgrDriver->AccurateAdvance(Current_PointVelocity, 
630                                    new_st_leng    641                                    new_st_length, eps_step );
631      //                                           642      //
632      // In this case it does not matter if it     643      // In this case it does not matter if it cannot advance the full distance
633   }                                               644   }
634                                                   645 
635   // If there was a memory of the step_length     646   // If there was a memory of the step_length actually required at the start 
636   // of the integration Step, this could be re    647   // of the integration Step, this could be re-used ...
637                                                   648 
638   G4cout.precision(14);                           649   G4cout.precision(14);
639                                                   650 
640   return Current_PointVelocity;                   651   return Current_PointVelocity;
641 }                                                 652 }
642                                                   653 
643 // ........................................... << 
644                                                   654 
645 std::ostream& operator<<( std::ostream& os, co << 655 // ......................................................................
                                                   >> 656 
                                                   >> 657 void
                                                   >> 658 G4ChordFinder::PrintStatistics()
646 {                                                 659 {
647    // Dumping the state of G4ChordFinder       << 660   // Print Statistics
648    os << "State of G4ChordFinder : " << std::e << 
649    os << "   delta_chord   = " <<  cf.fDeltaCh << 
650    os << "   Default d_c   = " <<  cf.fDefault << 
651                                                   661 
652    os << "   stats-verbose = " <<  cf.fStatsVe << 662   G4cout << "G4ChordFinder statistics report: " << G4endl;
                                                   >> 663   G4cout 
                                                   >> 664     << "  No trials: " << fTotalNoTrials_FNC
                                                   >> 665     << "  No Calls: "  << fNoCalls_FNC
                                                   >> 666     << "  Max-trial: " <<  fmaxTrials_FNC
                                                   >> 667     << G4endl; 
                                                   >> 668   G4cout 
                                                   >> 669     << "  Parameters: " 
                                                   >> 670     << "  fFirstFraction "  << fFirstFraction
                                                   >> 671     << "  fFractionLast "   << fFractionLast
                                                   >> 672     << "  fFractionNextEstimate " << fFractionNextEstimate
                                                   >> 673     << G4endl; 
                                                   >> 674 }
653                                                   675 
654    return os;                                  << 676 
                                                   >> 677 // ...........................................................................
                                                   >> 678 
                                                   >> 679 void G4ChordFinder::TestChordPrint( G4int    noTrials, 
                                                   >> 680                                     G4int    lastStepTrial, 
                                                   >> 681                                     G4double dChordStep, 
                                                   >> 682                                     G4double nextStepTrial )
                                                   >> 683 {
                                                   >> 684      G4int oldprec= G4cout.precision(5);
                                                   >> 685      G4cout << " ChF/fnc: notrial " << std::setw( 3) << noTrials 
                                                   >> 686             << " this_step= "       << std::setw(10) << lastStepTrial;
                                                   >> 687      if( std::fabs( (dChordStep / fDeltaChord) - 1.0 ) < 0.001 )
                                                   >> 688      {
                                                   >> 689        G4cout.precision(8);
                                                   >> 690      }
                                                   >> 691      else
                                                   >> 692      {
                                                   >> 693        G4cout.precision(6);
                                                   >> 694      }
                                                   >> 695      G4cout << " dChordStep=  " << std::setw(12) << dChordStep;
                                                   >> 696      if( dChordStep > fDeltaChord ) { G4cout << " d+"; }
                                                   >> 697      else                           { G4cout << " d-"; }
                                                   >> 698      G4cout.precision(5);
                                                   >> 699      G4cout <<  " new_step= "       << std::setw(10)
                                                   >> 700             << fLastStepEstimate_Unconstrained
                                                   >> 701             << " new_step_constr= " << std::setw(10)
                                                   >> 702             << lastStepTrial << G4endl;
                                                   >> 703      G4cout << " nextStepTrial = " << std::setw(10) << nextStepTrial << G4endl;
                                                   >> 704      G4cout.precision(oldprec);
655 }                                                 705 }
656                                                   706