1 | #include <TMath.h>
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2 | #include <TVectorD.h>
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3 | #include <TVector3.h>
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4 | #include <TMatrixD.h>
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5 | #include <TMatrixDSym.h>
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6 | #include "VertexFit.h"
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7 | //
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8 | // Constructors
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9 | //
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10 | // Empty
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11 | VertexFit::VertexFit()
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12 | {
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13 | fNtr = 0;
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14 | fVtxDone = kFALSE;
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15 | fVtxCst = kFALSE;
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16 | fxCst.ResizeTo(3);
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17 | fCovCst.ResizeTo(3, 3);
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18 | fXv.ResizeTo(3);
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19 | fcovXv.ResizeTo(3, 3);
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20 | }
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21 | // Parameters and covariances
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22 | VertexFit::VertexFit(Int_t Ntr, TVectorD** trkPar, TMatrixDSym** trkCov)
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23 | {
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24 | fNtr = Ntr;
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25 | fVtxDone = kFALSE;
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26 | fVtxCst = kFALSE;
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27 | fxCst.ResizeTo(3);
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28 | fCovCst.ResizeTo(3, 3);
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29 | fXv.ResizeTo(3);
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30 | fcovXv.ResizeTo(3, 3);
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31 | //
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32 | fPar = trkPar;
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33 | fCov = trkCov;
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34 | fChi2List.ResizeTo(Ntr);
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35 | //
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36 | ffi = new Double_t[Ntr]; // Fit phases
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37 | fx0i = new TVectorD * [Ntr]; // Track expansion points
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38 | for (Int_t i = 0; i < Ntr; i++) fx0i[i] = new TVectorD(3);
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39 | fai = new TVectorD * [Ntr]; // dx/dphi
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40 | for (Int_t i = 0; i < Ntr; i++) fai[i] = new TVectorD(3);
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41 | fa2i = new Double_t[Ntr]; // a'Wa
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42 | fDi = new TMatrixDSym * [Ntr]; // W-WBW
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43 | for (Int_t i = 0; i < Ntr; i++) fDi[i] = new TMatrixDSym(3);
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44 | fWi = new TMatrixDSym * [Ntr]; // (ACA')^-1
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45 | for (Int_t i = 0; i < Ntr; i++) fWi[i] = new TMatrixDSym(3);
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46 | fWinvi = new TMatrixDSym * [Ntr]; // ACA'
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47 | for (Int_t i = 0; i < Ntr; i++) fWinvi[i] = new TMatrixDSym(3);
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48 | }
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49 | // ObsTrk list
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50 | VertexFit::VertexFit(Int_t Ntr, ObsTrk** track)
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51 | {
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52 | fNtr = Ntr;
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53 | fVtxDone = kFALSE;
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54 | fVtxCst = kFALSE;
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55 | fxCst.ResizeTo(3);
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56 | fCovCst.ResizeTo(3, 3);
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57 | fXv.ResizeTo(3);
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58 | fcovXv.ResizeTo(3, 3);
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59 | //
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60 | fPar = new TVectorD * [Ntr];
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61 | fCov = new TMatrixDSym * [Ntr];
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62 | fChi2List.ResizeTo(Ntr);
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63 | for (Int_t i = 0; i < Ntr; i++)
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64 | {
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65 | fPar[i] = new TVectorD(track[i]->GetObsPar());
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66 | fCov[i] = new TMatrixDSym(track[i]->GetCov());
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67 | }
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68 | //
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69 | ffi = new Double_t[Ntr]; // Fit phases
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70 | fx0i = new TVectorD * [Ntr]; // Track expansion points
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71 | for (Int_t i = 0; i < Ntr; i++) fx0i[i] = new TVectorD(3);
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72 | fai = new TVectorD * [Ntr]; // dx/dphi
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73 | for (Int_t i = 0; i < Ntr; i++) fai[i] = new TVectorD(3);
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74 | fa2i = new Double_t[Ntr]; // a'Wa
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75 | fDi = new TMatrixDSym * [Ntr]; // W-WBW
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76 | for (Int_t i = 0; i < Ntr; i++) fDi[i] = new TMatrixDSym(3);
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77 | fWi = new TMatrixDSym * [Ntr]; // (ACA')^-1
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78 | for (Int_t i = 0; i < Ntr; i++) fWi[i] = new TMatrixDSym(3);
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79 | fWinvi = new TMatrixDSym * [Ntr]; // ACA'
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80 | for (Int_t i = 0; i < Ntr; i++) fWinvi[i] = new TMatrixDSym(3);
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81 | }
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82 | //
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83 | // Destructor
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84 | VertexFit::~VertexFit()
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85 | {
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86 | fxCst.Clear();
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87 | fCovCst.Clear();
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88 | fXv.Clear();
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89 | fcovXv.Clear();
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90 | fChi2List.Clear();
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91 | //
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92 | for (Int_t i = 0; i < fNtr; i++)
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93 | {
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94 | fPar[i]->Clear();
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95 | fCov[i]->Clear();
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96 | //
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97 | fx0i[i]->Clear(); delete fx0i[i];
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98 | fai[i]->Clear(); delete fai[i];
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99 | fDi[i]->Clear(); delete fDi[i];
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100 | fWi[i]->Clear(); delete fWi[i];
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101 | fWinvi[i]->Clear(); delete fWinvi[i];
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102 | }
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103 | fNtr = 0;
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104 | delete[] fPar;
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105 | delete[] fCov;
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106 | delete[] ffi;
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107 | delete[] fa2i;
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108 | delete[] fx0i;
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109 | delete[] fai;
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110 | delete[] fDi;
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111 | delete[] fWi;
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112 | delete[] fWinvi;
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113 | }
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114 | //
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115 | Double_t VertexFit::FastRv1(TVectorD p1, TVectorD p2)
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116 | {
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117 | //
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118 | // Find radius of intersection between two tracks in the transverse plane
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119 | //
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120 | // p = (D,phi, C, z0, ct)
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121 | //
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122 | // Define arrays
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123 | //
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124 | Double_t r1 = 1.0 / p1(2);
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125 | Double_t r2 = 1.0 / p2(2);
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126 | TVectorD x0 = Fill_x0(p1);
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127 | TVectorD y0 = Fill_x0(p2);
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128 | TVectorD n = Fill_a(p1, 0.0);
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129 | n *= r1;
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130 | TVectorD k = Fill_a(p2, 0.0);
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131 | k *= r2;
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132 | //
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133 | // Setup and solve linear system
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134 | //
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135 | Double_t nn = 0; for (Int_t i = 0; i < 3; i++)nn += n(i) * n(i);
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136 | Double_t nk = 0; for (Int_t i = 0; i < 3; i++)nk += n(i) * k(i);
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137 | Double_t kk = 0; for (Int_t i = 0; i < 3; i++)kk += k(i) * k(i);
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138 | Double_t discr = nn * kk - nk * nk;
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139 | TMatrixDSym H(2);
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140 | H(0, 0) = kk;
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141 | H(0, 1) = nk;
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142 | H(1, 0) = H(0, 1);
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143 | H(1, 1) = nn;
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144 | TVectorD c(2);
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145 | c(0) = 0; for (Int_t i = 0; i < 3; i++)c(0) += n(i) * (y0(i) - x0(i));
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146 | c(1) = 0; for (Int_t i = 0; i < 3; i++)c(1) += -k(i) * (y0(i) - x0(i));
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147 | TVectorD smin = (H * c);
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148 | smin *= 1.0 / discr;
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149 | //
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150 | TVectorD X = x0 + smin(0) * n;
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151 | TVectorD Y = y0 + smin(1) * k;
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152 | Double_t R1 = TMath::Sqrt(X(0) * X(0) + X(1) * X(1));
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153 | Double_t R2 = TMath::Sqrt(Y(0) * Y(0) + Y(1) * Y(1));
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154 | //
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155 | return 0.5 * (R1 + R2);
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156 | }
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157 | Double_t VertexFit::FastRv(TVectorD p1, TVectorD p2)
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158 | {
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159 | //
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160 | // Find radius of minimum distance
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161 | //
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162 | // p = (D,phi, C)
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163 | //
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164 | // Solving matrix
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165 | TMatrixDSym H(2);
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166 | H(0, 0) = -TMath::Cos(p2(1));
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167 | H(0, 1) = TMath::Cos(p1(1));
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168 | H(1, 0) = -TMath::Sin(p2(1));
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169 | H(1, 1) = TMath::Sin(p1(1));
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170 | Double_t Det = TMath::Sin(p2(1) - p1(1));
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171 | H *= 1.0 / Det;
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172 | //
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173 | // Convergence parameters
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174 | Int_t Ntry = 0;
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175 | Int_t NtryMax = 100;
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176 | Double_t eps = 1000.;
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177 | Double_t epsMin = 1.0e-6;
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178 | //
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179 | // Vertex finding loop
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180 | //
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181 | TVectorD cterm(2);
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182 | cterm(0) = p1(0);
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183 | cterm(1) = p2(0);
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184 | TVectorD xv(2);
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185 | Double_t R = 1000.;
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186 | while (eps > epsMin)
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187 | {
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188 | xv = H * cterm;
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189 | Ntry++;
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190 | if (Ntry > NtryMax)
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191 | {
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192 | std::cout << "FastRv: maximum number of iteration reached" << std::endl;
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193 | break;
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194 | }
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195 | Double_t Rnew = TMath::Sqrt(xv(0) * xv(0) + xv(1) * xv(1));
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196 | eps = Rnew - R;
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197 | R = Rnew;
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198 | cterm(0) = p1(2) * R * R;
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199 | cterm(1) = p2(2) * R * R;
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200 | }
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201 | //
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202 | return R;
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203 | }
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204 |
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205 | TMatrixDSym VertexFit::RegInv3(TMatrixDSym& Smat0)
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206 | {
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207 | //
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208 | // Regularized inversion of symmetric 3x3 matrix with positive diagonal elements
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209 | //
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210 | TMatrixDSym Smat = Smat0;
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211 | Int_t N = Smat.GetNrows();
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212 | if (N != 3)
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213 | {
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214 | std::cout << "RegInv3 called with matrix size != 3. Abort & return standard inversion." << std::endl;
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215 | return Smat.Invert();
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216 | }
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217 | TMatrixDSym D(N); D.Zero();
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218 | Bool_t dZero = kTRUE; // No elements less or equal 0 on the diagonal
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219 | for (Int_t i = 0; i < N; i++) if (Smat(i, i) <= 0.0)dZero = kFALSE;
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220 | if (dZero)
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221 | {
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222 | for (Int_t i = 0; i < N; i++) D(i, i) = 1.0 / TMath::Sqrt(Smat(i, i));
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223 | TMatrixDSym RegMat = Smat.Similarity(D);
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224 | TMatrixDSym Q(2);
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225 | for (Int_t i = 0; i < 2; i++)
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226 | {
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227 | for (Int_t j = 0; j < 2; j++)Q(i, j) = RegMat(i, j);
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228 | }
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229 | Double_t Det = 1 - Q(0, 1) * Q(1, 0);
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230 | TMatrixDSym H(2);
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231 | H = Q;
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232 | H(0, 1) = -Q(0, 1);
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233 | H(1, 0) = -Q(1, 0);
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234 | TVectorD p(2);
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235 | p(0) = RegMat(0, 2);
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236 | p(1) = RegMat(1, 2);
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237 | Double_t pHp = H.Similarity(p);
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238 | Double_t h = pHp - Det;
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239 | //
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240 | TMatrixDSym pp(2); pp.Rank1Update(p);
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241 | TMatrixDSym F = (h * H) - pp.Similarity(H);
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242 | F *= 1.0 / Det;
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243 | TVectorD b = H * p;
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244 | TMatrixDSym InvReg(3);
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245 | for (Int_t i = 0; i < 2; i++)
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246 | {
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247 | InvReg(i, 2) = b(i);
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248 | InvReg(2, i) = b(i);
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249 | for (Int_t j = 0; j < 2; j++) InvReg(i, j) = F(i, j);
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250 | }
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251 | InvReg(2, 2) = -Det;
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252 | //
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253 | InvReg *= 1.0 / h;
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254 | //
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255 | //
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256 | return InvReg.Similarity(D);
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257 | }
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258 | else
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259 | {
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260 | D.Zero();
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261 | for (Int_t i = 0; i < N; i++) D(i, i) = 1.0 / TMath::Sqrt(TMath::Abs(Smat(i, i)));
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262 | TMatrixDSym RegMat = Smat.Similarity(D);
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263 | RegMat.Invert();
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264 | return RegMat.Similarity(D);
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265 | }
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266 | }
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267 | //
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268 | //
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269 | //
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270 | TMatrixD VertexFit::Fill_A(TVectorD par, Double_t phi)
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271 | {
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272 | //
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273 | // Derivative of track 3D position vector with respect to track parameters at constant phase
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274 | //
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275 | // par = vector of track parameters
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276 | // phi = phase
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277 | //
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278 | TMatrixD A(3, 5);
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279 | //
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280 | // Decode input arrays
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281 | //
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282 | Double_t D = par(0);
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283 | Double_t p0 = par(1);
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284 | Double_t C = par(2);
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285 | Double_t z0 = par(3);
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286 | Double_t ct = par(4);
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287 | //
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288 | // Fill derivative matrix dx/d alpha
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289 | // D
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290 | A(0, 0) = -TMath::Sin(p0);
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291 | A(1, 0) = TMath::Cos(p0);
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292 | A(2, 0) = 0.0;
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293 | // phi0
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294 | A(0, 1) = -D * TMath::Cos(p0) + (TMath::Cos(phi + p0) - TMath::Cos(p0)) / (2 * C);
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295 | A(1, 1) = -D * TMath::Sin(p0) + (TMath::Sin(phi + p0) - TMath::Sin(p0)) / (2 * C);
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296 | A(2, 1) = 0.0;
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297 | // C
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298 | A(0, 2) = -(TMath::Sin(phi + p0) - TMath::Sin(p0)) / (2 * C * C);
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299 | A(1, 2) = (TMath::Cos(phi + p0) - TMath::Cos(p0)) / (2 * C * C);
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300 | A(2, 2) = -ct * phi / (2 * C * C);
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301 | // z0
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302 | A(0, 3) = 0.0;
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303 | A(1, 3) = 0.0;
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304 | A(2, 3) = 1.0;
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305 | // ct = lambda
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306 | A(0, 4) = 0.0;
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307 | A(1, 4) = 0.0;
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308 | A(2, 4) = phi / (2 * C);
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309 | //
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310 | return A;
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311 | }
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312 | //
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313 | TVectorD VertexFit::Fill_a(TVectorD par, Double_t phi)
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314 | {
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315 | //
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316 | // Derivative of track 3D position vector with respect to phase at constant track parameters
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317 | //
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318 | // par = vector of track parameters
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319 | // phi = phase
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320 | //
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321 | TVectorD a(3);
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322 | //
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323 | // Decode input arrays
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324 | //
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325 | Double_t D = par(0);
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326 | Double_t p0 = par(1);
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327 | Double_t C = par(2);
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328 | Double_t z0 = par(3);
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329 | Double_t ct = par(4);
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330 | //
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331 | a(0) = TMath::Cos(phi + p0) / (2 * C);
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332 | a(1) = TMath::Sin(phi + p0) / (2 * C);
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333 | a(2) = ct / (2 * C);
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334 | //
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335 | return a;
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336 | }
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337 | //
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338 | TVectorD VertexFit::Fill_x0(TVectorD par)
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339 | {
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340 | //
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341 | // Calculate track 3D position at R = |D| (minimum approach to z-axis)
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342 | //
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343 | TVectorD x0(3);
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344 | //
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345 | // Decode input arrays
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346 | //
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347 | Double_t D = par(0);
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348 | Double_t p0 = par(1);
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349 | Double_t C = par(2);
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350 | Double_t z0 = par(3);
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351 | Double_t ct = par(4);
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352 | //
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353 | x0(0) = -D * TMath::Sin(p0);
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354 | x0(1) = D * TMath::Cos(p0);
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355 | x0(2) = z0;
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356 | //
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357 | return x0;
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358 | }
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359 | //
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360 | TVectorD VertexFit::Fill_x(TVectorD par, Double_t phi)
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361 | {
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362 | //
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363 | // Calculate track 3D position for a given phase, phi
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364 | //
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365 | TVectorD x(3);
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366 | //
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367 | // Decode input arrays
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368 | //
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369 | Double_t D = par(0);
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370 | Double_t p0 = par(1);
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371 | Double_t C = par(2);
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372 | Double_t z0 = par(3);
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373 | Double_t ct = par(4);
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374 | //
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375 | TVectorD x0 = Fill_x0(par);
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376 | x(0) = x0(0) + (TMath::Sin(phi + p0) - TMath::Sin(p0)) / (2 * C);
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377 | x(1) = x0(1) - (TMath::Cos(phi + p0) - TMath::Cos(p0)) / (2 * C);
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378 | x(2) = x0(2) + ct * phi / (2 * C);
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379 | //
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380 | return x;
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381 | }
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382 | //
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383 | void VertexFit::VertexFinder()
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384 | {
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385 | //
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386 | // Vertex fit (units are meters)
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387 | //
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388 | // Initial variable definitions
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389 | TVectorD x(3);
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390 | TMatrixDSym covX(3);
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391 | TVectorD x0(3); for (Int_t v = 0; v < 3; v++)x0(v) = 100.; // set to large value
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392 | Double_t Chi2 = 0;
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393 | //
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394 | // Stored quantities
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395 | Double_t* fi = new Double_t[fNtr]; // Phases
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396 | TVectorD** x0i = new TVectorD * [fNtr]; // Track expansion point
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397 | TVectorD** ai = new TVectorD * [fNtr]; // dx/dphi
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398 | Double_t* a2i = new Double_t[fNtr]; // a'Wa
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399 | TMatrixDSym** Di = new TMatrixDSym * [fNtr]; // W-WBW
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400 | TMatrixDSym** Wi = new TMatrixDSym * [fNtr]; // (ACA')^-1
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401 | TMatrixDSym** Winvi = new TMatrixDSym * [fNtr]; // ACA'
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402 | //
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403 | // vertex radius approximation
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404 | // Maximum impact parameter
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405 | Double_t Rd = 0;
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406 | for (Int_t i = 0; i < fNtr; i++)
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407 | {
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408 | //ObsTrk* t = tracks[i];
|
---|
409 | TVectorD par = *fPar[i];
|
---|
410 | Double_t Dabs = TMath::Abs(par(0));
|
---|
411 | if (Dabs > Rd)Rd = Dabs;
|
---|
412 | }
|
---|
413 | //
|
---|
414 | // Find track pair with largest phi difference
|
---|
415 | Int_t isel = 0; Int_t jsel = 0; // selected track indices
|
---|
416 | Double_t dphiMax = 0.0; // Max phi difference
|
---|
417 |
|
---|
418 | for (Int_t i = 0; i < fNtr - 1; i++)
|
---|
419 | {
|
---|
420 | //ObsTrk* ti = tracks[i];
|
---|
421 | TVectorD pari = *fPar[i];
|
---|
422 | Double_t phi1 = pari(1);
|
---|
423 |
|
---|
424 | for (Int_t j = i + 1; j < fNtr; j++)
|
---|
425 | {
|
---|
426 | //ObsTrk* tj = tracks[j];
|
---|
427 | TVectorD parj = *fPar[j];
|
---|
428 | Double_t phi2 = parj(1);
|
---|
429 | Double_t dphi = TMath::Abs(phi2 - phi1);
|
---|
430 | if (dphi > TMath::Pi())dphi = TMath::TwoPi() - dphi;
|
---|
431 | if (dphi > dphiMax)
|
---|
432 | {
|
---|
433 | isel = i; jsel = j;
|
---|
434 | dphiMax = dphi;
|
---|
435 | }
|
---|
436 | }
|
---|
437 | }
|
---|
438 | //
|
---|
439 | TVectorD p1 = *fPar[isel];
|
---|
440 | TVectorD p2 = *fPar[jsel];
|
---|
441 | Double_t R = FastRv1(p1, p2);
|
---|
442 | if (R > 1000.0) R = Rd;
|
---|
443 | R = 0.9 * R + 0.1 * Rd;
|
---|
444 | //
|
---|
445 | // Iteration properties
|
---|
446 | //
|
---|
447 | Int_t Ntry = 0;
|
---|
448 | Int_t TryMax = 100;
|
---|
449 | Double_t eps = 1.0e-9; // vertex stability
|
---|
450 | Double_t epsi = 1000.;
|
---|
451 | //
|
---|
452 | while (epsi > eps && Ntry < TryMax) // Iterate until found vertex is stable
|
---|
453 | {
|
---|
454 | x.Zero();
|
---|
455 | TVectorD cterm(3); TMatrixDSym H(3); TMatrixDSym DW1D(3);
|
---|
456 | covX.Zero(); // Reset vertex covariance
|
---|
457 | cterm.Zero(); // Reset constant term
|
---|
458 | H.Zero(); // Reset H matrix
|
---|
459 | DW1D.Zero();
|
---|
460 | //
|
---|
461 | //std::cout << "VertexFinder: start loop on tracks" << std::endl;
|
---|
462 | for (Int_t i = 0; i < fNtr; i++)
|
---|
463 | {
|
---|
464 | // Get track helix parameters and their covariance matrix
|
---|
465 | TVectorD par = *fPar[i];
|
---|
466 | TMatrixDSym Cov = *fCov[i];
|
---|
467 |
|
---|
468 | Double_t fs;
|
---|
469 | if (Ntry <= 0) // Initialize all phases on first pass
|
---|
470 | {
|
---|
471 | Double_t D = par(0);
|
---|
472 | Double_t C = par(2);
|
---|
473 | Double_t arg = TMath::Max(1.0e-6, (R * R - D * D) / (1 + 2 * C * D));
|
---|
474 | fs = 2 * TMath::ASin(C * TMath::Sqrt(arg));
|
---|
475 | fi[i] = fs;
|
---|
476 | }
|
---|
477 | //
|
---|
478 | // Starting values
|
---|
479 | //
|
---|
480 | fs = fi[i]; // Get phase
|
---|
481 | //std::cout << "VertexFinder: phase fs set" << std::endl;
|
---|
482 | TVectorD xs = Fill_x(par, fs);
|
---|
483 | //std::cout << "VertexFinder: position xs set" << std::endl;
|
---|
484 | x0i[i] = new TVectorD(xs); // Start helix position
|
---|
485 | //std::cout << "VertexFinder: position x0i stored" << std::endl;
|
---|
486 | // W matrix = (A*C*A')^-1; W^-1 = A*C*A'
|
---|
487 | TMatrixD A = Fill_A(par, fs); // A = dx/da = derivatives wrt track parameters
|
---|
488 | //std::cout << "VertexFinder: derivatives A set" << std::endl;
|
---|
489 | TMatrixDSym Winv = Cov.Similarity(A); // W^-1 = A*C*A'
|
---|
490 | Winvi[i] = new TMatrixDSym(Winv); // Store W^-1 matrix
|
---|
491 | //std::cout << "VertexFinder: Winvi stored" << std::endl;
|
---|
492 | TMatrixDSym W = RegInv3(Winv); // W = (A*C*A')^-1
|
---|
493 | Wi[i] = new TMatrixDSym(W); // Store W matrix
|
---|
494 | //std::cout << "VertexFinder: Wi stored" << std::endl;
|
---|
495 | TVectorD a = Fill_a(par, fs); // a = dx/ds = derivatives wrt phase
|
---|
496 | //std::cout << "VertexFinder: derivatives a set" << std::endl;
|
---|
497 | ai[i] = new TVectorD(a); // Store a
|
---|
498 | //std::cout << "VertexFinder: derivatives a stored" << std::endl;
|
---|
499 | Double_t a2 = W.Similarity(a);
|
---|
500 | a2i[i] = a2; // Store a2
|
---|
501 | // Build D matrix
|
---|
502 | TMatrixDSym B(3);
|
---|
503 |
|
---|
504 | B.Rank1Update(a, 1.0);
|
---|
505 | B *= -1. / a2;
|
---|
506 | B.Similarity(W);
|
---|
507 | TMatrixDSym Ds = W + B; // D matrix
|
---|
508 | Di[i] = new TMatrixDSym(Ds); // Store D matrix
|
---|
509 | //std::cout << "VertexFinder: matrix Di stored" << std::endl;
|
---|
510 | TMatrixDSym DsW1Ds = Winv.Similarity(Ds); // Service matrix to calculate covX
|
---|
511 | DW1D += DsW1Ds;
|
---|
512 | // Update hessian
|
---|
513 | H += Ds;
|
---|
514 | // update constant term
|
---|
515 | cterm += Ds * xs;
|
---|
516 | } // End loop on tracks
|
---|
517 | //
|
---|
518 | // update vertex position
|
---|
519 | TMatrixDSym H1 = RegInv3(H);
|
---|
520 | x = H1 * cterm;
|
---|
521 | //std::cout << "VertexFinder: x vertex set" << std::endl;
|
---|
522 | // Update vertex covariance
|
---|
523 | covX = DW1D.Similarity(H1);
|
---|
524 | //std::cout << "VertexFinder: cov vertex set" << std::endl;
|
---|
525 | // Update phases and chi^2
|
---|
526 | Chi2 = 0.0;
|
---|
527 | for (Int_t i = 0; i < fNtr; i++)
|
---|
528 | {
|
---|
529 | TVectorD lambda = (*Di[i]) * (*x0i[i] - x);
|
---|
530 | TMatrixDSym Wm1 = *Winvi[i];
|
---|
531 | fChi2List(i) = Wm1.Similarity(lambda);
|
---|
532 | Chi2 += fChi2List(i);
|
---|
533 | TVectorD a = *ai[i];
|
---|
534 | TVectorD b = (*Wi[i]) * (x - *x0i[i]);
|
---|
535 | for (Int_t j = 0; j < 3; j++)fi[i] += a(j) * b(j) / a2i[i];
|
---|
536 | }
|
---|
537 |
|
---|
538 | //
|
---|
539 | TVectorD dx = x - x0;
|
---|
540 | x0 = x;
|
---|
541 | // update vertex stability
|
---|
542 | TMatrixDSym Hess = RegInv3(covX);
|
---|
543 | epsi = Hess.Similarity(dx);
|
---|
544 | Ntry++;
|
---|
545 | //
|
---|
546 | // Store result
|
---|
547 | //
|
---|
548 | fXv = x; // Vertex position
|
---|
549 | fcovXv = covX; // Vertex covariance
|
---|
550 | fChi2 = Chi2; // Vertex fit Chi2
|
---|
551 | //
|
---|
552 | // Store intermediate data
|
---|
553 | //
|
---|
554 |
|
---|
555 | //std::cout << "VertexFinder: before store intermediate data" << std::endl;
|
---|
556 | for (Int_t i = 0; i < fNtr; i++)
|
---|
557 | {
|
---|
558 | //std::cout << "VertexFinder: inside store intermediate data" << std::endl;
|
---|
559 | //std::cout << "i = " << i << ", fi[i] = " << fi[i] << std::endl;
|
---|
560 | //std::cout << "i = " << i << ", ffi[i] = " << ffi[i] << std::endl;
|
---|
561 | ffi[i] = fi[i]; // Fit phases
|
---|
562 | //std::cout << "VertexFinder: fi stored" << std::endl;
|
---|
563 | fx0i[i] = x0i[i]; // Track expansion points
|
---|
564 | //std::cout << "VertexFinder: x0i stored" << std::endl;
|
---|
565 | fai[i] = ai[i]; // dx/dphi
|
---|
566 | //std::cout << "VertexFinder: ai stored" << std::endl;
|
---|
567 | fa2i[i] = a2i[i]; // a'Wa
|
---|
568 | //std::cout << "VertexFinder: a2i stored" << std::endl;
|
---|
569 | fDi[i] = Di[i]; // W-WBW
|
---|
570 | //std::cout << "VertexFinder: Di stored" << std::endl;
|
---|
571 | fWi[i] = Wi[i]; // (ACA')^-1
|
---|
572 | //std::cout << "VertexFinder: Wi stored" << std::endl;
|
---|
573 | fWinvi[i] = Winvi[i]; // ACA'
|
---|
574 | //std::cout << "VertexFinder: Winvi stored" << std::endl;
|
---|
575 | }
|
---|
576 | //std::cout << "Iteration " << Ntry << " completed - Before cleanup" << std::endl;
|
---|
577 | //
|
---|
578 | // Cleanup
|
---|
579 | //
|
---|
580 | for (Int_t i = 0; i < fNtr; i++)
|
---|
581 | {
|
---|
582 | x0i[i]->Clear();
|
---|
583 | Winvi[i]->Clear();
|
---|
584 | Wi[i]->Clear();
|
---|
585 | ai[i]->Clear();
|
---|
586 | Di[i]->Clear();
|
---|
587 |
|
---|
588 | delete x0i[i];
|
---|
589 | delete Winvi[i];
|
---|
590 | delete Wi[i];
|
---|
591 | delete ai[i];
|
---|
592 | delete Di[i];
|
---|
593 | }
|
---|
594 |
|
---|
595 | //std::cout << "Iteration " << Ntry << " completed - After cleanup" << std::endl;
|
---|
596 | }
|
---|
597 | //
|
---|
598 | fVtxDone = kTRUE; // Set fitting completion flag
|
---|
599 | //
|
---|
600 | delete[] fi; // Phases
|
---|
601 | delete[] x0i; // Track expansion point
|
---|
602 | delete[] ai; // dx/dphi
|
---|
603 | delete[] a2i; // a'Wa
|
---|
604 | delete[] Di; // W-WBW
|
---|
605 | delete[] Wi; // (ACA')^-1
|
---|
606 | delete[] Winvi; // ACA'
|
---|
607 | }
|
---|
608 | //
|
---|
609 | TVectorD VertexFit::GetVtx()
|
---|
610 | {
|
---|
611 | //std::cout << "GetVtx: flag set to " << fVtxDone << std::endl;
|
---|
612 | if (!fVtxDone)VertexFinder();
|
---|
613 | return fXv;
|
---|
614 | }
|
---|
615 |
|
---|
616 | TMatrixDSym VertexFit::GetVtxCov()
|
---|
617 | {
|
---|
618 | if (!fVtxDone)VertexFinder();
|
---|
619 | return fcovXv;
|
---|
620 | }
|
---|
621 |
|
---|
622 | Double_t VertexFit::GetVtxChi2()
|
---|
623 | {
|
---|
624 | if (!fVtxDone)VertexFinder();
|
---|
625 | return fChi2;
|
---|
626 | }
|
---|
627 |
|
---|
628 | TVectorD VertexFit::GetVtxChi2List()
|
---|
629 | {
|
---|
630 | if (!fVtxDone)VertexFinder();
|
---|
631 | return fChi2List;
|
---|
632 | }
|
---|
633 | //
|
---|
634 | // Handle tracks/constraints
|
---|
635 | void VertexFit::AddVtxConstraint(TVectorD xv, TMatrixDSym cov) // Add gaussian vertex constraint
|
---|
636 | {
|
---|
637 | std::cout << "VertexFit::AddVtxConstraint: Not implemented yet" << std::endl;
|
---|
638 | }
|
---|
639 | //
|
---|
640 | void VertexFit::AddTrk(TVectorD par, TMatrixDSym Cov) // Add track to input list
|
---|
641 | {
|
---|
642 | std::cout << "VertexFit::AddTrk: Not implemented yet" << std::endl;
|
---|
643 | }
|
---|
644 | void VertexFit::RemoveTrk(Int_t iTrk) // Remove iTrk track
|
---|
645 | {
|
---|
646 | std::cout << "VertexFit::RemoveTrk: Not implemented yet" << std::endl;
|
---|
647 | }
|
---|