[537d24f] | 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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[91ef0b8] | 17 | fCovCst.ResizeTo(3, 3);
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[537d24f] | 18 | fXv.ResizeTo(3);
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[91ef0b8] | 19 | fcovXv.ResizeTo(3, 3);
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[537d24f] | 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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[91ef0b8] | 28 | fCovCst.ResizeTo(3, 3);
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[537d24f] | 29 | fXv.ResizeTo(3);
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[91ef0b8] | 30 | fcovXv.ResizeTo(3, 3);
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[537d24f] | 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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[91ef0b8] | 37 | fx0i = new TVectorD * [Ntr]; // Track expansion points
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[537d24f] | 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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[91ef0b8] | 42 | fDi = new TMatrixDSym * [Ntr]; // W-WBW
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[537d24f] | 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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[91ef0b8] | 56 | fCovCst.ResizeTo(3, 3);
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[537d24f] | 57 | fXv.ResizeTo(3);
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[91ef0b8] | 58 | fcovXv.ResizeTo(3, 3);
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[537d24f] | 59 | //
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[91ef0b8] | 60 | fPar = new TVectorD * [Ntr];
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| 61 | fCov = new TMatrixDSym * [Ntr];
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[537d24f] | 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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[127644a] | 86 | fxCst.Clear();
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[537d24f] | 87 | fCovCst.Clear();
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[127644a] | 88 | fXv.Clear();
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| 89 | fcovXv.Clear();
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[537d24f] | 90 | fChi2List.Clear();
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| 91 | //
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[91ef0b8] | 92 | for (Int_t i = 0; i < fNtr; i++)
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[537d24f] | 93 | {
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[127644a] | 94 | fPar[i]->Clear();
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[537d24f] | 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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[91ef0b8] | 145 | c(0) = 0; for (Int_t i = 0; i < 3; i++)c(0) += n(i) * (y0(i) - x0(i));
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[537d24f] | 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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[91ef0b8] | 155 | return 0.5 * (R1 + R2);
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[537d24f] | 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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[91ef0b8] | 167 | H(0, 1) = TMath::Cos(p1(1));
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[537d24f] | 168 | H(1, 0) = -TMath::Sin(p2(1));
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[91ef0b8] | 169 | H(1, 1) = TMath::Sin(p1(1));
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[537d24f] | 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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[127644a] | 192 | std::cout << "FastRv: maximum number of iteration reached" << std::endl;
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[537d24f] | 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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[91ef0b8] | 205 | TMatrixDSym VertexFit::RegInv3(TMatrixDSym& Smat0)
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[537d24f] | 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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[127644a] | 214 | std::cout << "RegInv3 called with matrix size != 3. Abort & return standard inversion." << std::endl;
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[537d24f] | 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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[91ef0b8] | 229 | Double_t Det = 1 - Q(0, 1) * Q(1, 0);
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[537d24f] | 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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[91ef0b8] | 238 | Double_t h = pHp - Det;
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[537d24f] | 239 | //
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| 240 | TMatrixDSym pp(2); pp.Rank1Update(p);
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[91ef0b8] | 241 | TMatrixDSym F = (h * H) - pp.Similarity(H);
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[537d24f] | 242 | F *= 1.0 / Det;
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[91ef0b8] | 243 | TVectorD b = H * p;
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[537d24f] | 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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[91ef0b8] | 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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[537d24f] | 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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[91ef0b8] | 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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[537d24f] | 296 | A(2, 1) = 0.0;
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| 297 | // C
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[91ef0b8] | 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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[537d24f] | 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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[91ef0b8] | 353 | x0(0) = -D * TMath::Sin(p0);
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| 354 | x0(1) = D * TMath::Cos(p0);
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[537d24f] | 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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[91ef0b8] | 378 | x(2) = x0(2) + ct * phi / (2 * C);
|
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[537d24f] | 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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[91ef0b8] | 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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[537d24f] | 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];
|
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| 409 | TVectorD par = *fPar[i];
|
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| 410 | Double_t Dabs = TMath::Abs(par(0));
|
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| 411 | if (Dabs > Rd)Rd = Dabs;
|
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| 412 | }
|
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| 413 | //
|
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| 414 | // Find track pair with largest phi difference
|
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[91ef0b8] | 415 | Int_t isel = 0; Int_t jsel = 0; // selected track indices
|
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[127644a] | 416 | Double_t dphiMax = 0.0; // Max phi difference
|
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[91ef0b8] | 417 |
|
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| 418 | for (Int_t i = 0; i < fNtr - 1; i++)
|
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[537d24f] | 419 | {
|
---|
| 420 | //ObsTrk* ti = tracks[i];
|
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| 421 | TVectorD pari = *fPar[i];
|
---|
| 422 | Double_t phi1 = pari(1);
|
---|
| 423 |
|
---|
[91ef0b8] | 424 | for (Int_t j = i + 1; j < fNtr; j++)
|
---|
[537d24f] | 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);
|
---|
[91ef0b8] | 442 | if (R > 1000.0) R = Rd;
|
---|
| 443 | R = 0.9 * R + 0.1 * Rd;
|
---|
[537d24f] | 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();
|
---|
[127644a] | 460 | //
|
---|
| 461 | //std::cout << "VertexFinder: start loop on tracks" << std::endl;
|
---|
[537d24f] | 462 | for (Int_t i = 0; i < fNtr; i++)
|
---|
| 463 | {
|
---|
[127644a] | 464 | // Get track helix parameters and their covariance matrix
|
---|
[537d24f] | 465 | TVectorD par = *fPar[i];
|
---|
[127644a] | 466 | TMatrixDSym Cov = *fCov[i];
|
---|
[91ef0b8] | 467 |
|
---|
[537d24f] | 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);
|
---|
[91ef0b8] | 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));
|
---|
[537d24f] | 475 | fi[i] = fs;
|
---|
| 476 | }
|
---|
| 477 | //
|
---|
| 478 | // Starting values
|
---|
| 479 | //
|
---|
[91ef0b8] | 480 | fs = fi[i]; // Get phase
|
---|
[127644a] | 481 | //std::cout << "VertexFinder: phase fs set" << std::endl;
|
---|
[537d24f] | 482 | TVectorD xs = Fill_x(par, fs);
|
---|
[127644a] | 483 | //std::cout << "VertexFinder: position xs set" << std::endl;
|
---|
[537d24f] | 484 | x0i[i] = new TVectorD(xs); // Start helix position
|
---|
[127644a] | 485 | //std::cout << "VertexFinder: position x0i stored" << std::endl;
|
---|
[537d24f] | 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
|
---|
[127644a] | 488 | //std::cout << "VertexFinder: derivatives A set" << std::endl;
|
---|
[537d24f] | 489 | TMatrixDSym Winv = Cov.Similarity(A); // W^-1 = A*C*A'
|
---|
| 490 | Winvi[i] = new TMatrixDSym(Winv); // Store W^-1 matrix
|
---|
[127644a] | 491 | //std::cout << "VertexFinder: Winvi stored" << std::endl;
|
---|
[537d24f] | 492 | TMatrixDSym W = RegInv3(Winv); // W = (A*C*A')^-1
|
---|
| 493 | Wi[i] = new TMatrixDSym(W); // Store W matrix
|
---|
[127644a] | 494 | //std::cout << "VertexFinder: Wi stored" << std::endl;
|
---|
[537d24f] | 495 | TVectorD a = Fill_a(par, fs); // a = dx/ds = derivatives wrt phase
|
---|
[127644a] | 496 | //std::cout << "VertexFinder: derivatives a set" << std::endl;
|
---|
[537d24f] | 497 | ai[i] = new TVectorD(a); // Store a
|
---|
[127644a] | 498 | //std::cout << "VertexFinder: derivatives a stored" << std::endl;
|
---|
[537d24f] | 499 | Double_t a2 = W.Similarity(a);
|
---|
| 500 | a2i[i] = a2; // Store a2
|
---|
| 501 | // Build D matrix
|
---|
[127644a] | 502 | TMatrixDSym B(3);
|
---|
[91ef0b8] | 503 |
|
---|
[537d24f] | 504 | B.Rank1Update(a, 1.0);
|
---|
| 505 | B *= -1. / a2;
|
---|
| 506 | B.Similarity(W);
|
---|
[91ef0b8] | 507 | TMatrixDSym Ds = W + B; // D matrix
|
---|
[537d24f] | 508 | Di[i] = new TMatrixDSym(Ds); // Store D matrix
|
---|
[127644a] | 509 | //std::cout << "VertexFinder: matrix Di stored" << std::endl;
|
---|
[537d24f] | 510 | TMatrixDSym DsW1Ds = Winv.Similarity(Ds); // Service matrix to calculate covX
|
---|
[127644a] | 511 | DW1D += DsW1Ds;
|
---|
[537d24f] | 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);
|
---|
[91ef0b8] | 520 | x = H1 * cterm;
|
---|
[127644a] | 521 | //std::cout << "VertexFinder: x vertex set" << std::endl;
|
---|
[537d24f] | 522 | // Update vertex covariance
|
---|
| 523 | covX = DW1D.Similarity(H1);
|
---|
[127644a] | 524 | //std::cout << "VertexFinder: cov vertex set" << std::endl;
|
---|
[537d24f] | 525 | // Update phases and chi^2
|
---|
| 526 | Chi2 = 0.0;
|
---|
| 527 | for (Int_t i = 0; i < fNtr; i++)
|
---|
| 528 | {
|
---|
[91ef0b8] | 529 | TVectorD lambda = (*Di[i]) * (*x0i[i] - x);
|
---|
[537d24f] | 530 | TMatrixDSym Wm1 = *Winvi[i];
|
---|
| 531 | fChi2List(i) = Wm1.Similarity(lambda);
|
---|
| 532 | Chi2 += fChi2List(i);
|
---|
| 533 | TVectorD a = *ai[i];
|
---|
[91ef0b8] | 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];
|
---|
[537d24f] | 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 |
|
---|
[127644a] | 555 | //std::cout << "VertexFinder: before store intermediate data" << std::endl;
|
---|
[537d24f] | 556 | for (Int_t i = 0; i < fNtr; i++)
|
---|
| 557 | {
|
---|
[127644a] | 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;
|
---|
[537d24f] | 561 | ffi[i] = fi[i]; // Fit phases
|
---|
[127644a] | 562 | //std::cout << "VertexFinder: fi stored" << std::endl;
|
---|
[537d24f] | 563 | fx0i[i] = x0i[i]; // Track expansion points
|
---|
[127644a] | 564 | //std::cout << "VertexFinder: x0i stored" << std::endl;
|
---|
[537d24f] | 565 | fai[i] = ai[i]; // dx/dphi
|
---|
[127644a] | 566 | //std::cout << "VertexFinder: ai stored" << std::endl;
|
---|
[537d24f] | 567 | fa2i[i] = a2i[i]; // a'Wa
|
---|
[127644a] | 568 | //std::cout << "VertexFinder: a2i stored" << std::endl;
|
---|
[537d24f] | 569 | fDi[i] = Di[i]; // W-WBW
|
---|
[127644a] | 570 | //std::cout << "VertexFinder: Di stored" << std::endl;
|
---|
[537d24f] | 571 | fWi[i] = Wi[i]; // (ACA')^-1
|
---|
[127644a] | 572 | //std::cout << "VertexFinder: Wi stored" << std::endl;
|
---|
[537d24f] | 573 | fWinvi[i] = Winvi[i]; // ACA'
|
---|
[127644a] | 574 | //std::cout << "VertexFinder: Winvi stored" << std::endl;
|
---|
[537d24f] | 575 | }
|
---|
[127644a] | 576 | //std::cout << "Iteration " << Ntry << " completed - Before cleanup" << std::endl;
|
---|
[537d24f] | 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 |
|
---|
[127644a] | 595 | //std::cout << "Iteration " << Ntry << " completed - After cleanup" << std::endl;
|
---|
[537d24f] | 596 | }
|
---|
| 597 | //
|
---|
| 598 | fVtxDone = kTRUE; // Set fitting completion flag
|
---|
| 599 | //
|
---|
[127644a] | 600 | delete[] fi; // Phases
|
---|
[537d24f] | 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 | {
|
---|
[127644a] | 611 | //std::cout << "GetVtx: flag set to " << fVtxDone << std::endl;
|
---|
[537d24f] | 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 | {
|
---|
[127644a] | 637 | std::cout << "VertexFit::AddVtxConstraint: Not implemented yet" << std::endl;
|
---|
[537d24f] | 638 | }
|
---|
| 639 | //
|
---|
| 640 | void VertexFit::AddTrk(TVectorD par, TMatrixDSym Cov) // Add track to input list
|
---|
| 641 | {
|
---|
[127644a] | 642 | std::cout << "VertexFit::AddTrk: Not implemented yet" << std::endl;
|
---|
[537d24f] | 643 | }
|
---|
| 644 | void VertexFit::RemoveTrk(Int_t iTrk) // Remove iTrk track
|
---|
| 645 | {
|
---|
[127644a] | 646 | std::cout << "VertexFit::RemoveTrk: Not implemented yet" << std::endl;
|
---|
[537d24f] | 647 | }
|
---|