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Please see the license in the file << 14 // * use. * 16 // * for the full disclaimer and the limitatio << 17 // * 15 // * * 18 // * This code implementation is the result << 16 // * This code implementation is the intellectual property of the * 19 // * technical work of the GEANT4 collaboratio << 17 // * GEANT4 collaboration. * 20 // * By using, copying, modifying or distri << 18 // * By copying, distributing or modifying the Program (or any work * 21 // * any work based on the software) you ag << 19 // * based on the Program) you indicate your acceptance of this * 22 // * use in resulting scientific publicati << 20 // * statement, and all its terms. * 23 // * acceptance of all terms of the Geant4 Sof << 24 // ******************************************* 21 // ******************************************************************** 25 // 22 // 26 // G4ChordFinder implementation << 27 // 23 // 28 // Author: J.Apostolakis - Design and implemen << 24 // $Id: G4ChordFinder.cc,v 1.32 2003/04/02 08:53:20 gcosmo Exp $ 29 // ------------------------------------------- << 25 // GEANT4 tag $Name: geant4-05-01-patch-01 $ 30 << 26 // 31 #include <iomanip> << 27 // >> 28 // 25.02.97 John Apostolakis, design and implimentation >> 29 // 05.03.97 V. Grichine , style modification 32 30 33 #include "G4ChordFinder.hh" 31 #include "G4ChordFinder.hh" 34 #include "G4SystemOfUnits.hh" << 32 #include "G4MagIntegratorDriver.hh" 35 #include "G4MagneticField.hh" << 36 #include "G4Mag_UsualEqRhs.hh" 33 #include "G4Mag_UsualEqRhs.hh" >> 34 #include "G4ClassicalRK4.hh" >> 35 // #include "G4Field.hh" >> 36 // #include "G4MagIntegratorStepper.hh" 37 #include "G4MagIntegratorDriver.hh" 37 #include "G4MagIntegratorDriver.hh" 38 // #include "G4ClassicalRK4.hh" << 38 #include "g4std/iomanip" 39 // #include "G4CashKarpRKF45.hh" << 40 // #include "G4NystromRK4.hh" << 41 // #include "G4BogackiShampine23.hh" << 42 // #include "G4BogackiShampine45.hh" << 43 << 44 #include "G4DormandPrince745.hh" << 45 39 46 // New templated stepper(s) -- avoid virtual c << 40 // For the moment fDeltaChord is a constant! 47 #include "G4TDormandPrince45.hh" << 48 41 49 // FSAL type driver / steppers ----- << 42 const G4double G4ChordFinder::fDefaultDeltaChord = 3. * mm; 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 43 58 // Templated type drivers ----- << 44 // .......................................................................... 59 #include "G4IntegrationDriver.hh" << 60 #include "G4InterpolationDriver.hh" << 61 45 62 #include "G4HelixHeum.hh" << 46 G4ChordFinder::G4ChordFinder( G4MagneticField* theMagField, 63 #include "G4BFieldIntegrationDriver.hh" << 47 G4double stepMinimum, >> 48 G4MagIntegratorStepper* pItsStepper ) >> 49 : fDeltaChord( fDefaultDeltaChord ) >> 50 { >> 51 // Construct the Chord Finder >> 52 // by creating in inverse order the Driver, the Stepper and EqRhs ... >> 53 G4Mag_EqRhs *pEquation = new G4Mag_UsualEqRhs(theMagField); >> 54 fEquation = pEquation; >> 55 fLastStepEstimate_Unconstrained = DBL_MAX; // Should move q, p to >> 56 // G4FieldTrack ?? >> 57 // --->> Charge Q = 0 >> 58 // --->> Momentum P = 1 NOMINAL VALUES !!!!!!!!!!!!!!!!!! 64 59 65 #include "G4QSSDriverCreator.hh" << 60 if( pItsStepper == 0 ) >> 61 { >> 62 pItsStepper = fDriversStepper = new G4ClassicalRK4(pEquation); >> 63 fAllocatedStepper= true; >> 64 } >> 65 else >> 66 { >> 67 fAllocatedStepper= false; >> 68 } >> 69 fIntgrDriver = new G4MagInt_Driver(stepMinimum, pItsStepper, >> 70 pItsStepper->GetNumberOfVariables() ); >> 71 } 66 72 67 #include "G4CachedMagneticField.hh" << 73 // ...................................................................... 68 74 69 #include <cassert> << 75 G4ChordFinder::~G4ChordFinder() 70 #include <memory> << 76 { >> 77 delete fEquation; // fIntgrDriver->pIntStepper->theEquation_Rhs; >> 78 if( fAllocatedStepper) >> 79 { >> 80 delete fDriversStepper; >> 81 } // fIntgrDriver->pIntStepper;} >> 82 delete fIntgrDriver; >> 83 } 71 84 72 G4bool G4ChordFinder::gVerboseCtor = false; << 85 // ...................................................................... 73 // ........................................... << 74 86 75 G4ChordFinder::G4ChordFinder(G4VIntegrationDri << 87 G4double 76 : fDefaultDeltaChord(0.25 * mm), fIntgrDrive << 88 G4ChordFinder::AdvanceChordLimited( G4FieldTrack& yCurrent, >> 89 G4double stepMax, >> 90 G4double epsStep ) 77 { 91 { 78 // Simple constructor -- it does not create << 92 G4double stepPossible; 79 if( gVerboseCtor ) << 93 G4double dyErr; >> 94 G4FieldTrack yEnd( yCurrent); >> 95 G4double startCurveLen= yCurrent.GetCurveLength(); >> 96 >> 97 #ifdef G4DEBUG_FIELD >> 98 static G4bool dbg= false; >> 99 if( dbg ) >> 100 G4cerr << "Entered AdvanceChordLimited with:\n yCurrent: " << yCurrent >> 101 << " and initial Step=stepMax=" << stepMax << " mm. " << G4endl; >> 102 #endif >> 103 >> 104 stepPossible= FindNextChord(yCurrent, stepMax, yEnd, dyErr, epsStep); >> 105 G4bool good_advance; >> 106 if ( dyErr < epsStep * stepPossible ) >> 107 { >> 108 // Accept this accuracy. >> 109 yCurrent = yEnd; >> 110 good_advance = true; >> 111 } >> 112 else 80 { 113 { 81 G4cout << "G4ChordFinder: Simple construct << 114 // Advance more accurately to "end of chord" >> 115 good_advance = fIntgrDriver->AccurateAdvance(yCurrent, stepPossible, epsStep); >> 116 #ifdef G4DEBUG_FIELD >> 117 if (dbg) G4cerr << "Accurate advance to end of chord attemped" >> 118 << "with result " << good_advance << G4endl ; >> 119 #endif >> 120 if ( ! good_advance ){ >> 121 // In this case the driver could not do the full distance >> 122 stepPossible= yCurrent.GetCurveLength()-startCurveLen; >> 123 } 82 } 124 } 83 << 125 84 fDeltaChord = fDefaultDeltaChord; // P << 126 #ifdef G4DEBUG_FIELD >> 127 if( dbg ) G4cerr << "Exiting FindNextChord Limited with:\n yCurrent: " >> 128 << yCurrent<< G4endl; >> 129 #endif >> 130 >> 131 return stepPossible; 85 } 132 } 86 133 87 // ........................................... << 134 // #define TEST_CHORD_PRINT 1 88 135 89 G4ChordFinder::G4ChordFinder( G4MagneticField* << 136 // ............................................................................ 90 G4double << 137 91 G4MagIntegratorS << 138 G4double 92 G4int << 139 G4ChordFinder::FindNextChord( const G4FieldTrack yStart, 93 : fDefaultDeltaChord(0.25 * mm) << 140 G4double stepMax, >> 141 G4FieldTrack& yEnd, // Endpoint >> 142 G4double& dyErr, // Error of endpoint >> 143 G4double ) >> 144 // Returns Length of Step taken 94 { 145 { 95 // Construct the Chord Finder << 146 // G4int stepRKnumber=0; 96 // by creating in inverse order the Driver, << 147 G4FieldTrack yCurrent= yStart; 97 constexpr G4int nVar6 = 6; // Components i << 148 G4double stepTrial; >> 149 G4double dydx[G4FieldTrack::ncompSVEC]; >> 150 >> 151 // 1.) Try to "leap" to end of interval >> 152 // 2.) Evaluate if resulting chord gives d_chord that is good enough. >> 153 // 2a.) If d_chord is not good enough, find one that is. 98 154 99 fDeltaChord = fDefaultDeltaChord; // P << 155 G4bool validEndPoint= false; >> 156 G4double dChordStep, oldStepTrial, stepOfLastGoodChord; 100 157 101 G4cout << " G4ChordFinder: stepperDriverId: << 158 fIntgrDriver-> GetDerivatives( yCurrent, dydx ) ; 102 159 103 G4bool useFSALstepper = (stepperDriverId << 160 G4int noTrials=0; 104 G4bool useTemplatedStepper= (stepperDriverId << 105 G4bool useRegularStepper = (stepperDriverId << 106 G4bool useBfieldDriver = (stepperDriverId << 107 G4bool useG4QSSDriver = (stepperDriverId << 108 << 109 if( stepperDriverId == kQss3DriverType) << 110 { << 111 stepperDriverId = kQss2DriverType; << 112 G4cout << " G4ChordFinder: QSS 3 is curren << 113 } << 114 161 115 using EquationType = G4Mag_UsualEqRhs; << 162 stepTrial = G4std::min( stepMax, 116 << 163 (1-perThousand)*fLastStepEstimate_Unconstrained ); 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 { << 143 G4cout << "G4ChordFinder 2nd Constructor << 144 G4cout << " Arguments: " << G4endl << 145 << " - min step = " << stepMinimum << 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 } << 156 #endif << 157 164 158 // useHigherStepper = forceHigherEffiencySte << 165 do >> 166 { >> 167 G4double stepForChord; // , stepForAccuracy; >> 168 >> 169 yCurrent = yStart; // Always start from initial point 159 170 160 auto pEquation = new G4Mag_UsualEqRhs(theMa << 171 fIntgrDriver->QuickAdvance( yCurrent, dydx, stepTrial, dChordStep, dyErr); 161 fEquation = pEquation; << 162 172 163 // G4MagIntegratorStepper* regularStepper = << 173 // First debug print 164 // G4VFSALIntegrationStepper* fsalStepper = << 165 // G4MagIntegratorStepper* oldFSALStepper = << 166 174 167 G4bool errorInStepperCreation = false; << 175 // We check whether the criterion is met here. >> 176 validEndPoint = AcceptableMissDist(dChordStep); >> 177 // && (dyErr < eps) ; 168 178 169 std::ostringstream message; // In case of f << 179 oldStepTrial = stepTrial; 170 180 171 if( pItsStepper != nullptr ) << 181 // This method estimates to step size for a good chord. 172 { << 182 stepForChord = NewStep(stepTrial, dChordStep, 173 if( gVerboseCtor ) << 183 fLastStepEstimate_Unconstrained ); 174 { << 175 G4cout << " G4ChordFinder: Creating G4I << 176 << " stepMinimum = " << stepMini << 177 << " numVar= " << pItsStepper->G << 178 } << 179 184 180 // Stepper type is not known - so must us << 185 if( ! validEndPoint ) { 181 if(pItsStepper->isQSS()) << 186 if( (stepForChord <= oldStepTrial) || (stepTrial<=0.0) ) 182 { << 187 stepTrial = stepForChord; 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 } << 202 else if ( useTemplatedStepper ) << 203 { << 204 if( gVerboseCtor ) << 205 { << 206 G4cout << " G4ChordFinder: Creating Te << 207 << TemplatedStepperName << G4en << 208 } << 209 // RegularStepperType* regularStepper = n << 210 auto templatedStepper = new TemplatedStep << 211 // *** *************** << 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 } << 232 << 233 } << 234 else if ( useRegularStepper ) // Plain st << 235 { << 236 auto regularStepper = new RegularStepperT << 237 // *** *************** << 238 fRegularStepperOwned = regularStepper; << 239 << 240 if( gVerboseCtor ) << 241 { << 242 G4cout << " G4ChordFinder: Creating Dr << 243 } << 244 << 245 if( regularStepper == nullptr ) << 246 { << 247 message << "Regular Stepper instantiat << 248 message << "G4ChordFinder: Attempted t << 249 << RegularStepperName << " typ << 250 errorInStepperCreation = true; << 251 } << 252 else << 253 { << 254 auto dp5= dynamic_cast<G4DormandPrince << 255 if( dp5 != nullptr ) << 256 { << 257 fIntgrDriver = new G4InterpolationD << 258 stepMinimum, << 259 if( gVerboseCtor ) << 260 { << 261 G4cout << " Using InterpolationD << 262 } << 263 } << 264 else 188 else 265 { << 189 stepTrial *= 0.1; 266 fIntgrDriver = new G4IntegrationDri << 190 #if 0 267 stepMinimum, << 191 // Possible complementary approach: 268 if( gVerboseCtor ) << 192 // Get the driver to calculate the new step size, if it is needed 269 { << 193 stepForAccuracy = 270 G4cout << " Using IntegrationDri << 194 fIntgrDriver->ComputeNewStepSize( dyErr/(epsStep*oldStepTrial), 271 } << 195 stepTrial ); 272 } << 196 stepTrial = G4std::min(stepForChord, stepForAccuracy); 273 } << 197 #endif 274 } << 198 275 else if ( useBfieldDriver ) << 199 // if(dbg) G4cerr<<"Dchord too big. Try new hstep="<<stepTrial<<G4endl; 276 { << 277 auto regularStepper = new G4DormandPrince << 278 // *** *************** << 279 // << 280 fRegularStepperOwned = regularStepper; << 281 << 282 { << 283 using SmallStepDriver = G4Interpolatio << 284 using LargeStepDriver = G4IntegrationD << 285 << 286 fLongStepper = std::make_unique<G4Heli << 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 } << 304 else if( useG4QSSDriver ) << 305 { << 306 if( stepperDriverId == kQss2DriverType ) << 307 { << 308 auto qssStepper2 = G4QSSDriverCreator:: << 309 if( gVerboseCtor ) << 310 { << 311 G4cout << "-- Created QSS-2 stepper" << 312 } << 313 fIntgrDriver = G4QSSDriverCreator::Crea << 314 } << 315 else << 316 { << 317 auto qssStepper3 = G4QSSDriverCreator:: << 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 } 200 } 328 } << 201 #ifdef TEST_CHORD_PRINT 329 else << 202 G4cout.precision(5); 330 { << 203 G4cout << " ChF/fnc: notrial " << G4std::setw( 3) << noTrials 331 auto fsalStepper= new NewFsalStepperType << 204 << " this_step= " << G4std::setw(10) << oldStepTrial; 332 // *** ****************** << 205 if( fabs( (dChordStep / fDeltaChord) - 1.0 ) < 0.001 ){ 333 fNewFSALStepperOwned = fsalStepper; << 206 G4cout.precision(8); 334 << 207 G4cout << " dChordStep= " << G4std::setw(12) << dChordStep; 335 if( fsalStepper == nullptr ) << 208 }else{ 336 { << 209 G4cout.precision(6); 337 message << "Stepper instantiation FAIL << 210 G4cout << " dChordStep= " << G4std::setw(12) << dChordStep; 338 message << "Attempted to instantiate " << 339 << NewFSALStepperName << " typ << 340 G4Exception("G4ChordFinder::G4ChordFin << 341 "GeomField1001", JustWarni << 342 errorInStepperCreation = true; << 343 } 211 } >> 212 if( dChordStep > fDeltaChord ) >> 213 G4cout << " d+"; 344 else 214 else 345 { << 215 G4cout << " d-"; 346 fIntgrDriver = new << 216 G4cout.precision(5); 347 G4FSALIntegrationDriver<NewFsalStep << 217 G4cout << " new_step= " << G4std::setw(10) 348 fsal << 218 << fLastStepEstimate_Unconstrained 349 // ==== Create the driver which k << 219 << " new_step_constr= " << G4std::setw(10) 350 << 220 << stepTrial << G4endl; 351 if( fIntgrDriver == nullptr ) << 221 #endif 352 { << 222 noTrials++; 353 message << "Using G4FSALIntegration << 354 << NewFSALStepperName << G4 << 355 message << "Integration Driver inst << 356 G4Exception("G4ChordFinder::G4Chord << 357 "GeomField1001", JustWa << 358 } << 359 } << 360 } 223 } >> 224 while( ! validEndPoint ); // End of do-while RKD 361 225 362 // -- Main work is now done << 226 stepOfLastGoodChord = stepTrial; 363 << 227 #ifdef TEST_CHORD_PRINT 364 // Now check that no error occured, and r << 228 static int dbg=0; 365 << 229 if( dbg ) 366 // To test failure to create driver << 230 G4cout << "ChordF/FindNextChord: NoTrials= " << noTrials 367 // delete fIntgrDriver; << 231 << " StepForGoodChord=" << G4std::setw(10) << stepTrial << G4endl; 368 // fIntgrDriver = nullptr; << 232 #endif 369 << 370 // Detect and report Error conditions << 371 // << 372 if( errorInStepperCreation || (fIntgrDriver << 373 { << 374 std::ostringstream errmsg; << 375 << 376 if( errorInStepperCreation ) << 377 { << 378 errmsg << "ERROR> Failure to create S << 379 << " ------------------- << 380 } << 381 if (fIntgrDriver == nullptr ) << 382 { << 383 errmsg << "ERROR> Failure to create I << 384 << G4endl << 385 << " ------------------- << 386 << G4endl; << 387 } << 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 } << 404 233 405 assert( ( pItsStepper != nullptr ) << 234 yEnd= yCurrent; 406 || ( fRegularStepperOwned != nullptr << 235 return stepTrial; 407 || ( fNewFSALStepperOwned != nullptr << 408 || useG4QSSDriver << 409 ); << 410 assert( fIntgrDriver != nullptr ); << 411 } 236 } 412 237 413 // ........................................... << 238 // ---------------------------------------------------------------------------- 414 << 239 #if 0 415 G4ChordFinder::~G4ChordFinder() << 240 // #ifdef G4VERBOSE 416 { << 241 if( dbg ) { 417 delete fEquation; << 242 G4cerr << "Returned from QuickAdvance with: yCur=" << yCurrent <<G4endl; 418 delete fRegularStepperOwned; << 243 G4cerr << " dChordStep= "<< dChordStep <<" dyErr=" << dyErr << G4endl; 419 delete fNewFSALStepperOwned; << 420 delete fCachedField; << 421 delete fIntgrDriver; << 422 } 244 } >> 245 #endif >> 246 // ---------------------------------------------------------------------------- 423 247 424 // ........................................... 248 // ........................................................................... 425 249 426 G4FieldTrack << 250 G4double G4ChordFinder::NewStep(G4double stepTrialOld, 427 G4ChordFinder::ApproxCurvePointS( const G4Fiel << 251 G4double dChordStep, // Curr. dchord achieved 428 const G4Fiel << 252 G4double& stepEstimate_Unconstrained ) 429 const G4Fiel << 253 // 430 const G4Thre << 254 // Is called to estimate the next step size, even for successful steps, 431 const G4Thre << 255 // in order to predict an accurate 'chord-sensitive' first step 432 const G4Thre << 256 // which is likely to assist in more performant 'stepping'. 433 G4bool << 257 // >> 258 434 { 259 { 435 // ApproxCurvePointS is 2nd implementation o << 260 G4double stepTrial; 436 // Use Brent Algorithm (or InvParabolic) whe << 261 static G4double lastStepTrial = 1., lastDchordStep= 1.; 437 // Given a starting curve point A (CurveA_Po << 438 // (CurveB_PointVelocity), a point E which i << 439 // and a point F which is on the curve (fir << 440 // point S on the curve closer to point E. << 441 // While advancing towards S utilise 'eps_st << 442 // relative accuracy of each Step. << 443 << 444 G4FieldTrack EndPoint(CurveA_PointVelocity); << 445 if(!first) { EndPoint = ApproxCurveV; } << 446 << 447 G4ThreeVector Point_A,Point_B; << 448 Point_A=CurveA_PointVelocity.GetPosition(); << 449 Point_B=CurveB_PointVelocity.GetPosition(); << 450 262 451 G4double xa,xb,xc,ya,yb,yc; << 263 #if 1 452 << 264 // const G4double threshold = 1.21, multiplier = 0.9; 453 // InverseParabolic. AF Intersects (First Pa << 265 // 0.9 < 1 / sqrt(1.21) 454 266 455 if(first) << 267 if (dChordStep > 0.0) 456 { 268 { 457 xa=0.; << 269 stepEstimate_Unconstrained = stepTrialOld*sqrt( fDeltaChord / dChordStep ); 458 ya=(PointG-Point_A).mag(); << 270 stepTrial = 0.98 * stepEstimate_Unconstrained; 459 xb=(Point_A-CurrentF_Point).mag(); << 271 } 460 yb=-(PointG-CurrentF_Point).mag(); << 461 xc=(Point_A-Point_B).mag(); << 462 yc=-(CurrentE_Point-Point_B).mag(); << 463 } << 464 else 272 else 465 { 273 { 466 xa=0.; << 274 // Should not update the Unconstrained Step estimate: incorrect! 467 ya=(Point_A-CurrentE_Point).mag(); << 275 stepTrial = stepTrialOld * 2.; 468 xb=(Point_A-CurrentF_Point).mag(); << 469 yb=(PointG-CurrentF_Point).mag(); << 470 xc=(Point_A-Point_B).mag(); << 471 yc=-(Point_B-PointG).mag(); << 472 if(xb==0.) << 473 { << 474 EndPoint = ApproxCurvePointV(CurveA_Poin << 475 CurrentE_Po << 476 return EndPoint; << 477 } << 478 } 276 } 479 277 480 const G4double tolerance = 1.e-12; << 278 // if ( dChordStep < threshold * fDeltaChord ){ 481 if(std::abs(ya)<=tolerance||std::abs(yc)<=to << 279 // stepTrial= stepTrialOld * multiplier; >> 280 // } >> 281 if( stepTrial <= 0.001 * stepTrialOld) >> 282 { >> 283 if ( dChordStep > 1000.0 * fDeltaChord ){ >> 284 stepTrial= stepTrialOld * 0.03; >> 285 }else{ >> 286 if ( dChordStep > 100. * fDeltaChord ){ >> 287 stepTrial= stepTrialOld * 0.1; >> 288 }else{ >> 289 // Try halving the length until dChordStep OK >> 290 stepTrial= stepTrialOld * 0.5; >> 291 } >> 292 } >> 293 }else if (stepTrial > 1000.0 * stepTrialOld) 482 { 294 { 483 ; // What to do for the moment: return the << 295 stepTrial= 1000.0 * stepTrialOld; 484 // then PropagatorInField will take care << 485 } 296 } 486 else << 487 { << 488 G4double test_step = InvParabolic(xa,ya,xb << 489 G4double curve; << 490 if(first) << 491 { << 492 curve=std::abs(EndPoint.GetCurveLength() << 493 -ApproxCurveV.GetCurveLeng << 494 } << 495 else << 496 { << 497 test_step = test_step - xb; << 498 curve=std::abs(EndPoint.GetCurveLength() << 499 -CurveB_PointVelocity.GetC << 500 xb = (CurrentF_Point-Point_B).mag(); << 501 } << 502 << 503 if(test_step<=0) { test_step=0.1*xb; } << 504 if(test_step>=xb) { test_step=0.5*xb; } << 505 if(test_step>=curve){ test_step=0.5*curve; << 506 << 507 if(curve*(1.+eps_step)<xb) // Similar to R << 508 { // G4VIntersect << 509 test_step=0.5*curve; << 510 } << 511 297 512 fIntgrDriver->AccurateAdvance(EndPoint,tes << 298 if( stepTrial == 0.0 ){ 513 << 299 stepTrial= 0.000001; 514 #ifdef G4DEBUG_FIELD << 515 // Printing Brent and Linear Approximation << 516 // << 517 G4cout << "G4ChordFinder::ApproxCurvePoint << 518 << test_step << " EndPoint = " << << 519 << 520 // Test Track << 521 // << 522 G4FieldTrack TestTrack( CurveA_PointVeloci << 523 TestTrack = ApproxCurvePointV( CurveA_Poin << 524 CurveB_Poin << 525 CurrentE_Po << 526 G4cout.precision(14); << 527 G4cout << "G4ChordFinder::BrentApprox = " << 528 G4cout << "G4ChordFinder::LinearApprox= " << 529 #endif << 530 } 300 } 531 return EndPoint; << 532 } << 533 301 >> 302 lastStepTrial = stepTrialOld; >> 303 lastDchordStep= dChordStep; >> 304 #else >> 305 if ( dChordStep > 1000. * fDeltaChord ){ >> 306 stepTrial= stepTrialOld * 0.03; >> 307 }else{ >> 308 if ( dChordStep > 100. * fDeltaChord ){ >> 309 stepTrial= stepTrialOld * 0.1; >> 310 }else{ >> 311 // Keep halving the length until dChordStep OK >> 312 stepTrial= stepTrialOld * 0.5; >> 313 } >> 314 } >> 315 #endif 534 316 535 // ........................................... << 317 // A more sophisticated chord-finder could figure out a better >> 318 // stepTrial, from dChordStep and the required d_geometry >> 319 // eg >> 320 // Calculate R, r_helix (eg at orig point) >> 321 // if( stepTrial < 2 pi R ) >> 322 // stepTrial = R arc_cos( 1 - fDeltaChord / r_helix ) >> 323 // else >> 324 // ?? >> 325 >> 326 return stepTrial; >> 327 } 536 328 537 G4FieldTrack G4ChordFinder:: << 329 // 538 ApproxCurvePointV( const G4FieldTrack& CurveA_ << 330 // Given a starting curve point A (CurveA_PointVelocity), a later 539 const G4FieldTrack& CurveB_ << 331 // curve point B (CurveB_PointVelocity) and a point E which is (generally) 540 const G4ThreeVector& Curren << 332 // not on the curve, find and return a point F which is on the curve and 541 G4double eps_step) << 333 // which is close to E. While advancing towards F utilise eps_step >> 334 // as a measure of the relative accuracy of each Step. >> 335 >> 336 G4FieldTrack >> 337 G4ChordFinder::ApproxCurvePointV( const G4FieldTrack& CurveA_PointVelocity, >> 338 const G4FieldTrack& CurveB_PointVelocity, >> 339 const G4ThreeVector& CurrentE_Point, >> 340 G4double eps_step) 542 { 341 { 543 // If r=|AE|/|AB|, and s=true path lenght (A << 342 // 1st implementation: 544 // return the point that is r*s along the cu << 343 // if r=|AE|/|AB|, and s=true path lenght (AB) 545 << 344 // return the point that is r*s along the curve! 546 G4FieldTrack Current_PointVelocity = Curve << 345 >> 346 G4FieldTrack Current_PointVelocity= CurveA_PointVelocity; 547 347 548 G4ThreeVector CurveA_Point= CurveA_PointVel 348 G4ThreeVector CurveA_Point= CurveA_PointVelocity.GetPosition(); 549 G4ThreeVector CurveB_Point= CurveB_PointVel 349 G4ThreeVector CurveB_Point= CurveB_PointVelocity.GetPosition(); 550 350 551 G4ThreeVector ChordAB_Vector= CurveB_Point 351 G4ThreeVector ChordAB_Vector= CurveB_Point - CurveA_Point; 552 G4ThreeVector ChordAE_Vector= CurrentE_Poin 352 G4ThreeVector ChordAE_Vector= CurrentE_Point - CurveA_Point; 553 353 554 G4double ABdist= ChordAB_Vector.mag(); 354 G4double ABdist= ChordAB_Vector.mag(); 555 G4double curve_length; // A curve length 355 G4double curve_length; // A curve length of AB 556 G4double AE_fraction; 356 G4double AE_fraction; 557 357 558 curve_length= CurveB_PointVelocity.GetCurveL 358 curve_length= CurveB_PointVelocity.GetCurveLength() 559 - CurveA_PointVelocity.GetCurveL 359 - CurveA_PointVelocity.GetCurveLength(); 560 << 360 561 G4double integrationInaccuracyLimit= std::ma << 361 // const 562 if( curve_length < ABdist * (1. - integratio << 362 G4double integrationInaccuracyLimit= G4std::max( perMillion, 0.5*eps_step ); 563 { << 363 if( curve_length < ABdist * (1. - integrationInaccuracyLimit) ){ 564 #ifdef G4DEBUG_FIELD 364 #ifdef G4DEBUG_FIELD 565 G4cerr << " Warning in G4ChordFinder::Appr 365 G4cerr << " Warning in G4ChordFinder::ApproxCurvePoint: " 566 << G4endl 366 << G4endl 567 << " The two points are further apa 367 << " The two points are further apart than the curve length " 568 << G4endl 368 << G4endl 569 << " Dist = " << ABdist 369 << " Dist = " << ABdist 570 << " curve length = " << curve_leng 370 << " curve length = " << curve_length 571 << " relativeDiff = " << (curve_len 371 << " relativeDiff = " << (curve_length-ABdist)/ABdist 572 << G4endl; 372 << G4endl; 573 if( curve_length < ABdist * (1. - 10*eps_s << 373 if( curve_length < ABdist * (1. - 10*eps_step) ) { 574 { << 374 G4cerr << " ERROR: the size of the above difference" 575 std::ostringstream message; << 375 << " exceeds allowed limits. Aborting." << G4endl; 576 message << "Unphysical curve length." << << 376 G4Exception("G4ChordFinder::ApproxCurvePoint > Unphysical curve length."); 577 << "The size of the above differ << 578 << G4endl << 579 << "Aborting."; << 580 G4Exception("G4ChordFinder::ApproxCurveP << 581 FatalException, message); << 582 } 377 } 583 #endif 378 #endif 584 // Take default corrective action: adjust << 379 // Take default corrective action: 585 // NOTE: this case only happens for relati << 380 // --> adjust the maximum curve length. 586 // curve_length = ABdist; << 381 // NOTE: this case only happens for relatively straight paths. >> 382 curve_length = ABdist; 587 } 383 } 588 384 589 G4double new_st_length; << 385 G4double new_st_length; 590 386 591 if ( ABdist > 0.0 ) << 387 if ( ABdist > 0.0 ){ 592 { << 593 AE_fraction = ChordAE_Vector.mag() / ABdi 388 AE_fraction = ChordAE_Vector.mag() / ABdist; 594 } << 389 }else{ 595 else << 596 { << 597 AE_fraction = 0.5; 390 AE_fraction = 0.5; // Guess .. ?; 598 #ifdef G4DEBUG_FIELD 391 #ifdef G4DEBUG_FIELD 599 G4cout << "Warning in G4ChordFinder::Appr << 392 G4cout << "Warning in G4ChordFinder::ApproxCurvePoint:" 600 << " A and B are the same point!" 393 << " A and B are the same point!" << G4endl 601 << " Chord AB length = " << ChordA 394 << " Chord AB length = " << ChordAE_Vector.mag() << G4endl 602 << G4endl; 395 << G4endl; 603 #endif 396 #endif 604 } 397 } 605 398 606 if( (AE_fraction> 1.0 + perMillion) || (AE_f << 399 if( (AE_fraction> 1.0 + perMillion) || (AE_fraction< 0.) ){ 607 { << 608 #ifdef G4DEBUG_FIELD 400 #ifdef G4DEBUG_FIELD 609 G4cerr << " G4ChordFinder::ApproxCurvePoin << 401 G4cerr << " G4ChordFinder::ApproxCurvePointV - Warning:" 610 << " Anomalous condition:AE > AB or 402 << " Anomalous condition:AE > AB or AE/AB <= 0 " << G4endl 611 << " AE_fraction = " << AE_fract 403 << " AE_fraction = " << AE_fraction << G4endl 612 << " Chord AE length = " << Chord 404 << " Chord AE length = " << ChordAE_Vector.mag() << G4endl 613 << " Chord AB length = " << ABdis 405 << " Chord AB length = " << ABdist << G4endl << G4endl; 614 G4cerr << " OK if this condition occurs af 406 G4cerr << " OK if this condition occurs after a recalculation of 'B'" 615 << G4endl << " Otherwise it is an e 407 << G4endl << " Otherwise it is an error. " << G4endl ; 616 #endif 408 #endif 617 // This course can now result if B has be 409 // This course can now result if B has been re-evaluated, 618 // without E being recomputed (1 July 99) << 410 // without E being recomputed (1 July 99) 619 // In this case this is not a "real error << 411 // In this case this is not a "real error" - but it undesired 620 // and we cope with it by a default corre << 412 // and we cope with it by a default corrective action ... 621 // << 622 AE_fraction = 0.5; 413 AE_fraction = 0.5; // Default value 623 } 414 } 624 415 625 new_st_length = AE_fraction * curve_length; << 416 new_st_length= AE_fraction * curve_length; 626 417 627 if ( AE_fraction > 0.0 ) << 418 G4bool good_advance; 628 { << 419 if ( AE_fraction > 0.0 ) { 629 fIntgrDriver->AccurateAdvance(Current_Poi << 420 good_advance = 630 new_st_leng << 421 fIntgrDriver->AccurateAdvance(Current_PointVelocity, 631 // << 422 new_st_length, >> 423 eps_step ); // Relative accuracy 632 // In this case it does not matter if it 424 // In this case it does not matter if it cannot advance the full distance 633 } 425 } 634 426 635 // If there was a memory of the step_length << 427 // If there was a memory of the step_length actually require at the start 636 // of the integration Step, this could be re 428 // of the integration Step, this could be re-used ... 637 429 638 G4cout.precision(14); << 639 << 640 return Current_PointVelocity; 430 return Current_PointVelocity; 641 } 431 } 642 432 643 // ........................................... << 644 << 645 std::ostream& operator<<( std::ostream& os, co << 646 { << 647 // Dumping the state of G4ChordFinder << 648 os << "State of G4ChordFinder : " << std::e << 649 os << " delta_chord = " << cf.fDeltaCh << 650 os << " Default d_c = " << cf.fDefault << 651 << 652 os << " stats-verbose = " << cf.fStatsVe << 653 433 654 return os; << 655 } << 656 434