[831] | 1 | // |
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| 2 | // ******************************************************************** |
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| 3 | // * License and Disclaimer * |
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| 4 | // * * |
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| 5 | // * The Geant4 software is copyright of the Copyright Holders of * |
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| 6 | // * the Geant4 Collaboration. It is provided under the terms and * |
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| 7 | // * conditions of the Geant4 Software License, included in the file * |
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| 8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
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| 9 | // * include a list of copyright holders. * |
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| 10 | // * * |
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| 11 | // * Neither the authors of this software system, nor their employing * |
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| 12 | // * institutes,nor the agencies providing financial support for this * |
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| 13 | // * work make any representation or warranty, express or implied, * |
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| 14 | // * regarding this software system or assume any liability for its * |
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| 15 | // * use. Please see the license in the file LICENSE and URL above * |
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| 16 | // * for the full disclaimer and the limitation of liability. * |
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| 17 | // * * |
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| 18 | // * This code implementation is the result of the scientific and * |
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| 19 | // * technical work of the GEANT4 collaboration. * |
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| 20 | // * By using, copying, modifying or distributing the software (or * |
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| 21 | // * any work based on the software) you agree to acknowledge its * |
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| 22 | // * use in resulting scientific publications, and indicate your * |
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| 23 | // * acceptance of all terms of the Geant4 Software license. * |
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| 24 | // ******************************************************************** |
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| 25 | // |
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| 26 | // |
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| 27 | // $Id: G4ChordFinder.cc,v 1.47 2006/06/29 18:23:32 gunter Exp $ |
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| 28 | // GEANT4 tag $Name: $ |
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| 29 | // |
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| 30 | // |
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| 31 | // 25.02.97 John Apostolakis, design and implimentation |
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| 32 | // 05.03.97 V. Grichine , style modification |
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| 33 | // ------------------------------------------------------------------- |
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| 34 | |
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| 35 | #include "G4ChordFinder.hh" |
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| 36 | #include "G4MagneticField.hh" |
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| 37 | #include "G4Mag_UsualEqRhs.hh" |
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| 38 | #include "G4ClassicalRK4.hh" |
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| 39 | |
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| 40 | #include <iomanip> |
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| 41 | |
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| 42 | // .......................................................................... |
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| 43 | |
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| 44 | G4ChordFinder::G4ChordFinder(G4MagInt_Driver* pIntegrationDriver) |
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| 45 | : fDefaultDeltaChord( 0.25 * mm ), |
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| 46 | fDeltaChord( fDefaultDeltaChord ), |
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| 47 | fAllocatedStepper(false), |
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| 48 | fEquation(0), |
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| 49 | fDriversStepper(0), |
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| 50 | fFirstFraction(0.999), fFractionLast(1.00), fFractionNextEstimate(0.98), |
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| 51 | fMultipleRadius(15.0), |
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| 52 | fTotalNoTrials_FNC(0), fNoCalls_FNC(0), fmaxTrials_FNC(0), |
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| 53 | fStatsVerbose(0) |
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| 54 | { |
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| 55 | // Simple constructor which does not create equation, .. |
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| 56 | // fDeltaChord= fDefaultDeltaChord; |
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| 57 | fIntgrDriver= pIntegrationDriver; |
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| 58 | fAllocatedStepper= false; |
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| 59 | fLastStepEstimate_Unconstrained = DBL_MAX; // Should move q, p to |
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| 60 | |
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| 61 | SetFractions_Last_Next( fFractionLast, fFractionNextEstimate); |
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| 62 | // check the values and set the other parameters |
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| 63 | } |
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| 64 | |
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| 65 | // .......................................................................... |
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| 66 | |
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| 67 | G4ChordFinder::G4ChordFinder( G4MagneticField* theMagField, |
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| 68 | G4double stepMinimum, |
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| 69 | G4MagIntegratorStepper* pItsStepper ) |
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| 70 | : fDefaultDeltaChord( 0.25 * mm ), |
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| 71 | fDeltaChord( fDefaultDeltaChord ), |
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| 72 | fAllocatedStepper(false), |
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| 73 | fEquation(0), |
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| 74 | fDriversStepper(0), |
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| 75 | fFirstFraction(0.999), fFractionLast(1.00), fFractionNextEstimate(0.98), |
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| 76 | fMultipleRadius(15.0), |
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| 77 | fTotalNoTrials_FNC(0), fNoCalls_FNC(0), fmaxTrials_FNC(0), |
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| 78 | fStatsVerbose(0) |
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| 79 | { |
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| 80 | // Construct the Chord Finder |
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| 81 | // by creating in inverse order the Driver, the Stepper and EqRhs ... |
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| 82 | G4Mag_EqRhs *pEquation = new G4Mag_UsualEqRhs(theMagField); |
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| 83 | fEquation = pEquation; |
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| 84 | fLastStepEstimate_Unconstrained = DBL_MAX; // Should move q, p to |
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| 85 | // G4FieldTrack ?? |
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| 86 | |
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| 87 | SetFractions_Last_Next( fFractionLast, fFractionNextEstimate); |
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| 88 | // check the values and set the other parameters |
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| 89 | |
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| 90 | // --->> Charge Q = 0 |
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| 91 | // --->> Momentum P = 1 NOMINAL VALUES !!!!!!!!!!!!!!!!!! |
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| 92 | |
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| 93 | if( pItsStepper == 0 ) |
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| 94 | { |
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| 95 | pItsStepper = fDriversStepper = new G4ClassicalRK4(pEquation); |
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| 96 | fAllocatedStepper= true; |
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| 97 | } |
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| 98 | else |
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| 99 | { |
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| 100 | fAllocatedStepper= false; |
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| 101 | } |
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| 102 | fIntgrDriver = new G4MagInt_Driver(stepMinimum, pItsStepper, |
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| 103 | pItsStepper->GetNumberOfVariables() ); |
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| 104 | } |
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| 105 | |
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| 106 | // ...................................................................... |
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| 107 | |
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| 108 | void |
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| 109 | G4ChordFinder::SetFractions_Last_Next( G4double fractLast, G4double fractNext ) |
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| 110 | { |
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| 111 | // Use -1.0 as request for Default. |
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| 112 | if( fractLast == -1.0 ) fractLast = 1.0; // 0.9; |
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| 113 | if( fractNext == -1.0 ) fractNext = 0.98; // 0.9; |
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| 114 | |
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| 115 | // fFirstFraction = 0.999; // Orig 0.999 A safe value, range: ~ 0.95 - 0.999 |
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| 116 | // fMultipleRadius = 15.0; // For later use, range: ~ 2 - 20 |
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| 117 | |
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| 118 | if( fStatsVerbose ) { |
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| 119 | G4cout << " ChordFnd> Trying to set fractions: " |
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| 120 | << " first " << fFirstFraction |
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| 121 | << " last " << fractLast |
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| 122 | << " next " << fractNext |
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| 123 | << " and multiple " << fMultipleRadius |
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| 124 | << G4endl; |
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| 125 | } |
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| 126 | |
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| 127 | if( (fractLast > 0.0) && (fractLast <=1.0) ) |
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| 128 | { fFractionLast= fractLast; } |
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| 129 | else |
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| 130 | G4cerr << "G4ChordFinder:: SetFractions_Last_Next: Invalid " |
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| 131 | << " fraction Last = " << fractLast |
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| 132 | << " must be 0 < fractionLast <= 1 " << G4endl; |
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| 133 | if( (fractNext > 0.0) && (fractNext <1.0) ) |
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| 134 | { fFractionNextEstimate = fractNext; } |
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| 135 | else |
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| 136 | G4cerr << "G4ChordFinder:: SetFractions_Last_Next: Invalid " |
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| 137 | << " fraction Next = " << fractNext |
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| 138 | << " must be 0 < fractionNext < 1 " << G4endl; |
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| 139 | } |
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| 140 | |
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| 141 | // ...................................................................... |
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| 142 | |
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| 143 | G4ChordFinder::~G4ChordFinder() |
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| 144 | { |
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| 145 | delete fEquation; // fIntgrDriver->pIntStepper->theEquation_Rhs; |
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| 146 | if( fAllocatedStepper) |
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| 147 | { |
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| 148 | delete fDriversStepper; |
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| 149 | } // fIntgrDriver->pIntStepper;} |
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| 150 | delete fIntgrDriver; |
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| 151 | |
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| 152 | if( fStatsVerbose ) { PrintStatistics(); } |
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| 153 | } |
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| 154 | |
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| 155 | void |
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| 156 | G4ChordFinder::PrintStatistics() |
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| 157 | { |
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| 158 | // Print Statistics |
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| 159 | G4cout << "G4ChordFinder statistics report: " << G4endl; |
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| 160 | G4cout |
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| 161 | << " No trials: " << fTotalNoTrials_FNC |
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| 162 | << " No Calls: " << fNoCalls_FNC |
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| 163 | << " Max-trial: " << fmaxTrials_FNC |
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| 164 | << G4endl; |
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| 165 | G4cout |
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| 166 | << " Parameters: " |
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| 167 | << " fFirstFraction " << fFirstFraction |
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| 168 | << " fFractionLast " << fFractionLast |
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| 169 | << " fFractionNextEstimate " << fFractionNextEstimate |
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| 170 | << G4endl; |
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| 171 | } |
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| 172 | |
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| 173 | // ...................................................................... |
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| 174 | |
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| 175 | G4double |
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| 176 | G4ChordFinder::AdvanceChordLimited( G4FieldTrack& yCurrent, |
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| 177 | G4double stepMax, |
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| 178 | G4double epsStep, |
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| 179 | const G4ThreeVector latestSafetyOrigin, |
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| 180 | G4double latestSafetyRadius |
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| 181 | ) |
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| 182 | { |
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| 183 | G4double stepPossible; |
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| 184 | G4double dyErr; |
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| 185 | G4FieldTrack yEnd( yCurrent); |
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| 186 | G4double startCurveLen= yCurrent.GetCurveLength(); |
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| 187 | |
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| 188 | G4double nextStep; |
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| 189 | // ************* |
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| 190 | stepPossible= FindNextChord(yCurrent, stepMax, yEnd, dyErr, epsStep, &nextStep |
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| 191 | , latestSafetyOrigin, latestSafetyRadius |
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| 192 | ); |
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| 193 | // ************* |
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| 194 | G4bool good_advance; |
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| 195 | if ( dyErr < epsStep * stepPossible ) |
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| 196 | { |
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| 197 | // Accept this accuracy. |
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| 198 | yCurrent = yEnd; |
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| 199 | good_advance = true; |
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| 200 | } |
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| 201 | else |
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| 202 | { |
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| 203 | // Advance more accurately to "end of chord" |
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| 204 | // *************** |
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| 205 | good_advance = fIntgrDriver->AccurateAdvance(yCurrent, stepPossible, epsStep, nextStep); |
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| 206 | // *************** |
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| 207 | if ( ! good_advance ){ |
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| 208 | // In this case the driver could not do the full distance |
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| 209 | stepPossible= yCurrent.GetCurveLength()-startCurveLen; |
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| 210 | } |
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| 211 | } |
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| 212 | |
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| 213 | #ifdef G4DEBUG_FIELD |
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| 214 | G4cout << "Exiting FindNextChord Limited with:" << G4endl |
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| 215 | << " yCurrent: " << yCurrent<< G4endl; |
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| 216 | #endif |
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| 217 | |
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| 218 | return stepPossible; |
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| 219 | } |
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| 220 | |
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| 221 | // #define TEST_CHORD_PRINT 1 |
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| 222 | |
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| 223 | // ............................................................................ |
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| 224 | |
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| 225 | G4double |
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| 226 | G4ChordFinder::FindNextChord( const G4FieldTrack yStart, |
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| 227 | G4double stepMax, |
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| 228 | G4FieldTrack& yEnd, // Endpoint |
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| 229 | G4double& dyErrPos, // Error of endpoint |
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| 230 | G4double epsStep, |
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| 231 | G4double* pStepForAccuracy, |
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| 232 | const G4ThreeVector, // latestSafetyOrigin, |
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| 233 | G4double // latestSafetyRadius |
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| 234 | ) |
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| 235 | // Returns Length of Step taken |
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| 236 | { |
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| 237 | // G4int stepRKnumber=0; |
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| 238 | G4FieldTrack yCurrent= yStart; |
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| 239 | G4double stepTrial, stepForAccuracy; |
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| 240 | G4double dydx[G4FieldTrack::ncompSVEC]; |
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| 241 | |
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| 242 | // 1.) Try to "leap" to end of interval |
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| 243 | // 2.) Evaluate if resulting chord gives d_chord that is good enough. |
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| 244 | // 2a.) If d_chord is not good enough, find one that is. |
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| 245 | |
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| 246 | G4bool validEndPoint= false; |
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| 247 | G4double dChordStep, lastStepLength; // stepOfLastGoodChord; |
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| 248 | |
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| 249 | fIntgrDriver-> GetDerivatives( yCurrent, dydx ) ; |
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| 250 | |
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| 251 | G4int noTrials=0; |
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| 252 | const G4double safetyFactor= fFirstFraction; // 0.975 or 0.99 ? was 0.999 |
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| 253 | |
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| 254 | stepTrial = std::min( stepMax, |
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| 255 | safetyFactor * fLastStepEstimate_Unconstrained ); |
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| 256 | |
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| 257 | G4double newStepEst_Uncons= 0.0; |
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| 258 | do |
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| 259 | { |
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| 260 | G4double stepForChord; |
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| 261 | yCurrent = yStart; // Always start from initial point |
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| 262 | |
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| 263 | // ************ |
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| 264 | fIntgrDriver->QuickAdvance( yCurrent, dydx, stepTrial, |
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| 265 | dChordStep, dyErrPos); |
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| 266 | // ************ |
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| 267 | |
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| 268 | // We check whether the criterion is met here. |
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| 269 | validEndPoint = AcceptableMissDist(dChordStep); |
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| 270 | // && (dyErrPos < eps) ; |
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| 271 | |
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| 272 | lastStepLength = stepTrial; |
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| 273 | |
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| 274 | // This method estimates to step size for a good chord. |
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| 275 | stepForChord = NewStep(stepTrial, dChordStep, newStepEst_Uncons ); |
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| 276 | |
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| 277 | if( ! validEndPoint ) { |
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| 278 | if( stepTrial<=0.0 ) |
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| 279 | stepTrial = stepForChord; |
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| 280 | else if (stepForChord <= stepTrial) |
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| 281 | // Reduce by a fraction, possibly up to 20% |
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| 282 | stepTrial = std::min( stepForChord, |
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| 283 | fFractionLast * stepTrial); |
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| 284 | else |
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| 285 | stepTrial *= 0.1; |
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| 286 | |
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| 287 | // if(dbg) G4cerr<<"Dchord too big. Try new hstep="<<stepTrial<<G4endl; |
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| 288 | } |
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| 289 | // #ifdef TEST_CHORD_PRINT |
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| 290 | // TestChordPrint( noTrials, lastStepLength, dChordStep, stepTrial ); |
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| 291 | // #endif |
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| 292 | |
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| 293 | noTrials++; |
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| 294 | } |
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| 295 | while( ! validEndPoint ); // End of do-while RKD |
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| 296 | |
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| 297 | if( newStepEst_Uncons > 0.0 ){ |
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| 298 | fLastStepEstimate_Unconstrained= newStepEst_Uncons; |
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| 299 | } |
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| 300 | |
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| 301 | AccumulateStatistics( noTrials ); |
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| 302 | |
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| 303 | // stepOfLastGoodChord = stepTrial; |
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| 304 | |
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| 305 | if( pStepForAccuracy ){ |
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| 306 | // Calculate the step size required for accuracy, if it is needed |
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| 307 | G4double dyErr_relative = dyErrPos/(epsStep*lastStepLength); |
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| 308 | if( dyErr_relative > 1.0 ) { |
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| 309 | stepForAccuracy = |
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| 310 | fIntgrDriver->ComputeNewStepSize( dyErr_relative, |
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| 311 | lastStepLength ); |
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| 312 | }else{ |
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| 313 | stepForAccuracy = 0.0; // Convention to show step was ok |
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| 314 | } |
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| 315 | *pStepForAccuracy = stepForAccuracy; |
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| 316 | } |
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| 317 | |
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| 318 | #ifdef TEST_CHORD_PRINT |
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| 319 | static int dbg=0; |
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| 320 | if( dbg ) |
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| 321 | G4cout << "ChordF/FindNextChord: NoTrials= " << noTrials |
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| 322 | << " StepForGoodChord=" << std::setw(10) << stepTrial << G4endl; |
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| 323 | #endif |
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| 324 | |
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| 325 | yEnd= yCurrent; |
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| 326 | return stepTrial; |
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| 327 | } |
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| 328 | |
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| 329 | // ---------------------------------------------------------------------------- |
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| 330 | #if 0 |
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| 331 | // #ifdef G4VERBOSE |
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| 332 | if( dbg ) { |
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| 333 | G4cerr << "Returned from QuickAdvance with: yCur=" << yCurrent <<G4endl; |
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| 334 | G4cerr << " dChordStep= "<< dChordStep <<" dyErr=" << dyErr << G4endl; |
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| 335 | } |
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| 336 | #endif |
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| 337 | // ---------------------------------------------------------------------------- |
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| 338 | |
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| 339 | // ........................................................................... |
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| 340 | |
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| 341 | G4double G4ChordFinder::NewStep(G4double stepTrialOld, |
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| 342 | G4double dChordStep, // Curr. dchord achieved |
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| 343 | G4double& stepEstimate_Unconstrained ) |
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| 344 | // |
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| 345 | // Is called to estimate the next step size, even for successful steps, |
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| 346 | // in order to predict an accurate 'chord-sensitive' first step |
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| 347 | // which is likely to assist in more performant 'stepping'. |
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| 348 | // |
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| 349 | |
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| 350 | { |
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| 351 | G4double stepTrial; |
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| 352 | static G4double lastStepTrial = 1., lastDchordStep= 1.; |
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| 353 | |
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| 354 | #if 1 |
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| 355 | // const G4double threshold = 1.21, multiplier = 0.9; |
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| 356 | // 0.9 < 1 / std::sqrt(1.21) |
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| 357 | |
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| 358 | if (dChordStep > 0.0) |
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| 359 | { |
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| 360 | stepEstimate_Unconstrained = stepTrialOld*std::sqrt( fDeltaChord / dChordStep ); |
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| 361 | // stepTrial = 0.98 * stepEstimate_Unconstrained; |
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| 362 | stepTrial = fFractionNextEstimate * stepEstimate_Unconstrained; |
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| 363 | } |
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| 364 | else |
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| 365 | { |
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| 366 | // Should not update the Unconstrained Step estimate: incorrect! |
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| 367 | stepTrial = stepTrialOld * 2.; |
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| 368 | } |
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| 369 | |
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| 370 | // if ( dChordStep < threshold * fDeltaChord ){ |
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| 371 | // stepTrial= stepTrialOld * multiplier; |
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| 372 | // } |
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| 373 | if( stepTrial <= 0.001 * stepTrialOld) |
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| 374 | { |
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| 375 | if ( dChordStep > 1000.0 * fDeltaChord ){ |
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| 376 | stepTrial= stepTrialOld * 0.03; |
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| 377 | }else{ |
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| 378 | if ( dChordStep > 100. * fDeltaChord ){ |
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| 379 | stepTrial= stepTrialOld * 0.1; |
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| 380 | }else{ |
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| 381 | // Try halving the length until dChordStep OK |
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| 382 | stepTrial= stepTrialOld * 0.5; |
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| 383 | } |
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| 384 | } |
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| 385 | }else if (stepTrial > 1000.0 * stepTrialOld) |
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| 386 | { |
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| 387 | stepTrial= 1000.0 * stepTrialOld; |
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| 388 | } |
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| 389 | |
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| 390 | if( stepTrial == 0.0 ){ |
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| 391 | stepTrial= 0.000001; |
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| 392 | } |
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| 393 | |
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| 394 | lastStepTrial = stepTrialOld; |
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| 395 | lastDchordStep= dChordStep; |
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| 396 | #else |
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| 397 | if ( dChordStep > 1000. * fDeltaChord ){ |
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| 398 | stepTrial= stepTrialOld * 0.03; |
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| 399 | }else{ |
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| 400 | if ( dChordStep > 100. * fDeltaChord ){ |
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| 401 | stepTrial= stepTrialOld * 0.1; |
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| 402 | }else{ |
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| 403 | // Keep halving the length until dChordStep OK |
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| 404 | stepTrial= stepTrialOld * 0.5; |
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| 405 | } |
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| 406 | } |
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| 407 | #endif |
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| 408 | |
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| 409 | // A more sophisticated chord-finder could figure out a better |
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| 410 | // stepTrial, from dChordStep and the required d_geometry |
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| 411 | // eg |
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| 412 | // Calculate R, r_helix (eg at orig point) |
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| 413 | // if( stepTrial < 2 pi R ) |
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| 414 | // stepTrial = R arc_cos( 1 - fDeltaChord / r_helix ) |
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| 415 | // else |
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| 416 | // ?? |
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| 417 | |
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| 418 | return stepTrial; |
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| 419 | } |
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| 420 | |
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| 421 | // |
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| 422 | // Given a starting curve point A (CurveA_PointVelocity), a later |
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| 423 | // curve point B (CurveB_PointVelocity) and a point E which is (generally) |
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| 424 | // not on the curve, find and return a point F which is on the curve and |
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| 425 | // which is close to E. While advancing towards F utilise eps_step |
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| 426 | // as a measure of the relative accuracy of each Step. |
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| 427 | |
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| 428 | G4FieldTrack |
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| 429 | G4ChordFinder::ApproxCurvePointV( const G4FieldTrack& CurveA_PointVelocity, |
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| 430 | const G4FieldTrack& CurveB_PointVelocity, |
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| 431 | const G4ThreeVector& CurrentE_Point, |
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| 432 | G4double eps_step) |
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| 433 | { |
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| 434 | // 1st implementation: |
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| 435 | // if r=|AE|/|AB|, and s=true path lenght (AB) |
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| 436 | // return the point that is r*s along the curve! |
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| 437 | |
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| 438 | G4FieldTrack Current_PointVelocity= CurveA_PointVelocity; |
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| 439 | |
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| 440 | G4ThreeVector CurveA_Point= CurveA_PointVelocity.GetPosition(); |
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| 441 | G4ThreeVector CurveB_Point= CurveB_PointVelocity.GetPosition(); |
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| 442 | |
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| 443 | G4ThreeVector ChordAB_Vector= CurveB_Point - CurveA_Point; |
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| 444 | G4ThreeVector ChordAE_Vector= CurrentE_Point - CurveA_Point; |
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| 445 | |
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| 446 | G4double ABdist= ChordAB_Vector.mag(); |
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| 447 | G4double curve_length; // A curve length of AB |
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| 448 | G4double AE_fraction; |
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| 449 | |
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| 450 | curve_length= CurveB_PointVelocity.GetCurveLength() |
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| 451 | - CurveA_PointVelocity.GetCurveLength(); |
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| 452 | |
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| 453 | // const |
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| 454 | G4double integrationInaccuracyLimit= std::max( perMillion, 0.5*eps_step ); |
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| 455 | if( curve_length < ABdist * (1. - integrationInaccuracyLimit) ){ |
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| 456 | #ifdef G4DEBUG_FIELD |
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| 457 | G4cerr << " Warning in G4ChordFinder::ApproxCurvePoint: " |
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| 458 | << G4endl |
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| 459 | << " The two points are further apart than the curve length " |
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| 460 | << G4endl |
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| 461 | << " Dist = " << ABdist |
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| 462 | << " curve length = " << curve_length |
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| 463 | << " relativeDiff = " << (curve_length-ABdist)/ABdist |
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| 464 | << G4endl; |
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| 465 | if( curve_length < ABdist * (1. - 10*eps_step) ) { |
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| 466 | G4cerr << " ERROR: the size of the above difference" |
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| 467 | << " exceeds allowed limits. Aborting." << G4endl; |
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| 468 | G4Exception("G4ChordFinder::ApproxCurvePointV()", "PrecisionError", |
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| 469 | FatalException, "Unphysical curve length."); |
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| 470 | } |
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| 471 | #endif |
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| 472 | // Take default corrective action: |
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| 473 | // --> adjust the maximum curve length. |
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| 474 | // NOTE: this case only happens for relatively straight paths. |
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| 475 | curve_length = ABdist; |
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| 476 | } |
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| 477 | |
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| 478 | G4double new_st_length; |
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| 479 | |
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| 480 | if ( ABdist > 0.0 ){ |
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| 481 | AE_fraction = ChordAE_Vector.mag() / ABdist; |
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| 482 | }else{ |
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| 483 | AE_fraction = 0.5; // Guess .. ?; |
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| 484 | #ifdef G4DEBUG_FIELD |
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| 485 | G4cout << "Warning in G4ChordFinder::ApproxCurvePoint:" |
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| 486 | << " A and B are the same point!" << G4endl |
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| 487 | << " Chord AB length = " << ChordAE_Vector.mag() << G4endl |
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| 488 | << G4endl; |
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| 489 | #endif |
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| 490 | } |
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| 491 | |
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| 492 | if( (AE_fraction> 1.0 + perMillion) || (AE_fraction< 0.) ){ |
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| 493 | #ifdef G4DEBUG_FIELD |
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| 494 | G4cerr << " G4ChordFinder::ApproxCurvePointV - Warning:" |
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| 495 | << " Anomalous condition:AE > AB or AE/AB <= 0 " << G4endl |
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| 496 | << " AE_fraction = " << AE_fraction << G4endl |
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| 497 | << " Chord AE length = " << ChordAE_Vector.mag() << G4endl |
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| 498 | << " Chord AB length = " << ABdist << G4endl << G4endl; |
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| 499 | G4cerr << " OK if this condition occurs after a recalculation of 'B'" |
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| 500 | << G4endl << " Otherwise it is an error. " << G4endl ; |
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| 501 | #endif |
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| 502 | // This course can now result if B has been re-evaluated, |
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| 503 | // without E being recomputed (1 July 99) |
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| 504 | // In this case this is not a "real error" - but it undesired |
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| 505 | // and we cope with it by a default corrective action ... |
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| 506 | AE_fraction = 0.5; // Default value |
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| 507 | } |
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| 508 | |
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| 509 | new_st_length= AE_fraction * curve_length; |
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| 510 | |
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| 511 | G4bool good_advance; |
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| 512 | if ( AE_fraction > 0.0 ) { |
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| 513 | good_advance = |
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| 514 | fIntgrDriver->AccurateAdvance(Current_PointVelocity, |
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| 515 | new_st_length, |
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| 516 | eps_step ); // Relative accuracy |
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| 517 | // In this case it does not matter if it cannot advance the full distance |
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| 518 | } |
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| 519 | |
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| 520 | // If there was a memory of the step_length actually require at the start |
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| 521 | // of the integration Step, this could be re-used ... |
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| 522 | |
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| 523 | return Current_PointVelocity; |
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| 524 | } |
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| 525 | |
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| 526 | void |
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| 527 | G4ChordFinder::TestChordPrint( G4int noTrials, |
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| 528 | G4int lastStepTrial, |
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| 529 | G4double dChordStep, |
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| 530 | G4double nextStepTrial ) |
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| 531 | { |
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| 532 | G4int oldprec= G4cout.precision(5); |
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| 533 | G4cout << " ChF/fnc: notrial " << std::setw( 3) << noTrials |
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| 534 | << " this_step= " << std::setw(10) << lastStepTrial; |
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| 535 | if( std::fabs( (dChordStep / fDeltaChord) - 1.0 ) < 0.001 ){ |
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| 536 | G4cout.precision(8); |
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| 537 | }else{ G4cout.precision(6); } |
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| 538 | G4cout << " dChordStep= " << std::setw(12) << dChordStep; |
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| 539 | if( dChordStep > fDeltaChord ) { G4cout << " d+"; } |
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| 540 | else { G4cout << " d-"; } |
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| 541 | G4cout.precision(5); |
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| 542 | G4cout << " new_step= " << std::setw(10) |
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| 543 | << fLastStepEstimate_Unconstrained |
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| 544 | << " new_step_constr= " << std::setw(10) |
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| 545 | << lastStepTrial << G4endl; |
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| 546 | G4cout << " nextStepTrial = " << std::setw(10) << nextStepTrial << G4endl; |
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| 547 | G4cout.precision(oldprec); |
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| 548 | } |
---|