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TFitParticleMCSpher.cc
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1 // Classname: TFitParticleMCSpher
2 // Author: Jan E. Sundermann, Verena Klose (TU Dresden)
3 
4 
5 //________________________________________________________________
6 //
7 // TFitParticleMCSpher::
8 // --------------------
9 //
10 // Particle with spherical parametrization of the momentum 4vector and
11 // constant mass (3 free parameters). The parametrization is chosen as
12 // follows:
13 //
14 // p = (r, theta, phi)
15 // E(fit) = Sqrt( |p|^2 + m^2 )
16 //
17 
18 #include <iostream>
21 #include "TMath.h"
22 
23 
24 //----------------
25 // Constructor --
26 //----------------
29 {
30  init( 0, 0., 0);
31 }
32 
34  :TAbsFitParticle( fitParticle.GetName(), fitParticle.GetTitle() )
35 {
36 
37  _nPar = fitParticle._nPar;
38  _u1 = fitParticle._u1;
39  _u2 = fitParticle._u2;
40  _u3 = fitParticle._u3;
41  _covMatrix.ResizeTo( fitParticle._covMatrix );
42  _covMatrix = fitParticle._covMatrix;
43  _iniparameters.ResizeTo( fitParticle._iniparameters );
44  _iniparameters = fitParticle._iniparameters;
45  _parameters.ResizeTo( fitParticle._parameters );
46  _parameters = fitParticle._parameters;
47  _pini = fitParticle._pini;
48  _pcurr = fitParticle._pcurr;
49 
50 }
51 
52 TFitParticleMCSpher::TFitParticleMCSpher(TVector3* p, Double_t M, const TMatrixD* theCovMatrix)
54 {
55  init(p, M, theCovMatrix);
56 }
57 
58 TFitParticleMCSpher::TFitParticleMCSpher(const TString &name, const TString &title,
59  TVector3* p, Double_t M, const TMatrixD* theCovMatrix)
60  :TAbsFitParticle(name, title)
61 {
62  init(p, M, theCovMatrix);
63 }
64 
65 TAbsFitParticle* TFitParticleMCSpher::clone( const TString& newname ) const {
66  // Returns a copy of itself
67 
68  TAbsFitParticle* myclone = new TFitParticleMCSpher( *this );
69  if ( newname.Length() > 0 ) myclone->SetName(newname);
70  return myclone;
71 
72 }
73 
74 //--------------
75 // Destructor --
76 //--------------
78 
79 }
80 
81 
82 //--------------
83 // Operations --
84 //--------------
85 void TFitParticleMCSpher::init(TVector3* p, Double_t M, const TMatrixD* theCovMatrix) {
86 
87  _nPar = 3;
88  setIni4Vec(p, M);
89  setCovMatrix(theCovMatrix);
90 
91 }
92 
93 TLorentzVector* TFitParticleMCSpher::calc4Vec( const TMatrixD* params ) {
94  // Calculates a 4vector corresponding to the given
95  // parameter values
96 
97  if (params == 0) {
98  return 0;
99  }
100 
101  if ( params->GetNcols() != 1 || params->GetNrows() !=_nPar ) {
102  edm::LogError ("WrongMatrixSize")
103  << GetName() << "::calc4Vec - Parameter matrix has wrong size.";
104  return 0;
105  }
106 
107  Double_t r = (*params)(0,0);
108  Double_t theta = (*params)(1,0);
109  Double_t phi = (*params)(2,0);
110 
111  Double_t X = r*TMath::Cos(phi)*TMath::Sin(theta);
112  Double_t Y = r*TMath::Sin(phi)*TMath::Sin(theta);
113  Double_t Z = r*TMath::Cos(theta);
114  Double_t E = TMath::Sqrt( X*X + Y*Y + Z*Z + _pini.M2() );
115 
116  TLorentzVector* vec = new TLorentzVector( X, Y, Z, E );
117  return vec;
118 
119 }
120 
121 void TFitParticleMCSpher::setIni4Vec(const TLorentzVector* pini) {
122  // Set the initial 4vector. Will also set the
123  // inital parameter values
124 
125  TVector3 vec( pini->Vect() );
126  setIni4Vec( &vec, pini->M() );
127 
128 }
129 
130 void TFitParticleMCSpher::setIni4Vec(const TVector3* p, Double_t M) {
131  // Set the initial 4vector. Will also set the
132  // inital parameter values
133 
134  if ( p == 0 ) {
135 
136  _u1.SetXYZ(0., 0., 0.);
137  _u3.SetXYZ(0., 0., 0.);
138  _u2.SetXYZ(0., 0., 0.);
139  _pini.SetXYZM(0., 0., 0., M);
140  _pcurr = _pini;
141 
142  _iniparameters.ResizeTo(_nPar,1);
143  _iniparameters(0,0) = 0.;
144  _parameters.ResizeTo(_nPar,1);
146 
147  } else {
148 
149  _pini.SetXYZM( p->x(), p->y(), p->z(), M);
150  _pcurr = _pini;
151 
152  Double_t r = _pini.P();
153  Double_t theta = _pini.Theta();
154  Double_t phi = _pini.Phi();
155 
156  _iniparameters.ResizeTo(_nPar,1);
157  _iniparameters(0,0) = r;
158  _iniparameters(1,0) = theta;
159  _iniparameters(2,0) = phi;
160  _parameters.ResizeTo(_nPar,1);
162 
163  _u1.SetXYZ( TMath::Cos(phi)*TMath::Sin(theta), TMath::Sin(phi)*TMath::Sin(theta), TMath::Cos(theta) );
164  _u2.SetXYZ( TMath::Cos(phi)*TMath::Cos(theta), TMath::Sin(phi)*TMath::Cos(theta), -1.*TMath::Sin(theta) );
165  _u3.SetXYZ( -1.*TMath::Sin(phi), TMath::Cos(phi), 0. );
166 
167  }
168 
169 }
170 
172  // returns derivative dP/dy with P=(p,E) and y=(r, theta, phi)
173  // the free parameters of the fit. The columns of the matrix contain
174  // (dP/dr, dP/dtheta, ...).
175 
176  TMatrixD* DerivativeMatrix = new TMatrixD(4,3);
177  (*DerivativeMatrix) *= 0.;
178 
179  Double_t r = _parameters(0,0);
180  Double_t theta = _parameters(1,0);
181  Double_t phi = _parameters(2,0);
182 
183  //1st column: dP/dr
184  (*DerivativeMatrix)(0,0) = TMath::Cos(phi)*TMath::Sin(theta);
185  (*DerivativeMatrix)(1,0) = TMath::Sin(phi)*TMath::Sin(theta);
186  (*DerivativeMatrix)(2,0) = TMath::Cos(theta);
187  (*DerivativeMatrix)(3,0) = r/_pcurr.E();
188 
189  //2nd column: dP/dtheta
190  (*DerivativeMatrix)(0,1) = r*TMath::Cos(phi)*TMath::Cos(theta);
191  (*DerivativeMatrix)(1,1) = r*TMath::Sin(phi)*TMath::Cos(theta);
192  (*DerivativeMatrix)(2,1) = -1.*r*TMath::Sin(theta);
193  (*DerivativeMatrix)(3,1) = 0.;
194 
195  //3rd column: dP/dphi
196  (*DerivativeMatrix)(0,2) = -1.*r*TMath::Sin(phi)*TMath::Sin(theta);
197  (*DerivativeMatrix)(1,2) = r*TMath::Cos(phi)*TMath::Sin(theta);;
198  (*DerivativeMatrix)(2,2) = 0.;
199  (*DerivativeMatrix)(3,2) = 0.;
200 
201  return DerivativeMatrix;
202 
203 }
204 
205 TMatrixD* TFitParticleMCSpher::transform(const TLorentzVector& vec) {
206  // Returns the parameters corresponding to the given
207  // 4vector
208 
209  // retrieve parameters
210  TMatrixD* tparams = new TMatrixD( _nPar, 1 );
211  (*tparams)(0,0) = vec.P();
212  (*tparams)(1,0) = vec.Theta();
213  (*tparams)(2,0) = vec.Phi();
214 
215  return tparams;
216 
217 }
const double Z[kNumberCalorimeter]
void init(TVector3 *p, Double_t M, const TMatrixD *theCovMatrix)
Geom::Theta< T > theta() const
#define X(str)
Definition: MuonsGrabber.cc:48
virtual TMatrixD * getDerivative()
TLorentzVector _pini
TMatrixD _parameters
TLorentzVector _pcurr
virtual void setCovMatrix(const TMatrixD *theCovMatrix)
virtual TMatrixD * transform(const TLorentzVector &vec)
virtual TAbsFitParticle * clone(const TString &newname=TString("")) const
TMatrixD _iniparameters
virtual void setIni4Vec(const TLorentzVector *pini)
virtual TLorentzVector * calc4Vec(const TMatrixD *params)