1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
16 ////////////////////////////////////////////////////////////////////////////////
18 // This class contains all code which is used to compute any of the values
19 // which can be of interest within a resonance analysis. Besides the obvious
20 // invariant mass, it allows to compute other utility values on all possible
21 // targets, in order to allow a wide spectrum of binning and checks.
22 // When needed, this object can also define a binning in the variable which
23 // it is required to compute, which is used for initializing axes of output
24 // histograms (see AliRsnFunction).
25 // The value computation requires this object to be passed the object whose
26 // informations will be used. This object can be of any allowed input type
27 // (track, pair, event), then this class must inherit from AliRsnTarget.
28 // Then, when value computation is attempted, a check on target type is done
29 // and computation is successful only if expected target matches that of the
31 // In some cases, the value computation can require a support external object,
32 // which must then be passed to this class. It can be of any type inheriting
35 // authors: A. Pulvirenti (alberto.pulvirenti@ct.infn.it)
36 // M. Vala (martin.vala@cern.ch)
38 ////////////////////////////////////////////////////////////////////////////////
40 #include "Riostream.h"
44 #include "AliRsnMiniPair.h"
45 #include "AliRsnMiniEvent.h"
46 #include "AliRsnMiniParticle.h"
48 #include "AliRsnMiniValue.h"
50 ClassImp(AliRsnMiniValue)
52 //_____________________________________________________________________________
53 AliRsnMiniValue::AliRsnMiniValue(EType type, Bool_t useMC) :
54 TNamed(ValueName(type, useMC), ""),
63 //_____________________________________________________________________________
64 AliRsnMiniValue::AliRsnMiniValue(const AliRsnMiniValue ©) :
67 fUseMCInfo(copy.fUseMCInfo)
74 //_____________________________________________________________________________
75 AliRsnMiniValue &AliRsnMiniValue::operator=(const AliRsnMiniValue ©)
78 // Assignment operator.
79 // Works like copy constructor.
81 TNamed::operator=(copy);
85 fUseMCInfo = copy.fUseMCInfo;
90 //_____________________________________________________________________________
91 const char *AliRsnMiniValue::TypeName(EType type)
94 // This method returns a string to give a name to each possible
99 case kVz: return "EventVz";
100 case kMult: return "EventMult";
101 case kPlaneAngle: return "EventPlane";
102 case kLeadingPt: return "EventLeadingPt";
103 case kPt: return "Pt";
104 case kPz: return "Pz";
105 case kInvMass: return "InvMass";
106 case kInvMassRes: return "InvMassResolution";
107 case kInvMassDiff: return "InvMassDifference";
108 case kEta: return "Eta";
109 case kMt: return "Mt";
111 case kPtRatio: return "PtRatio";
112 case kDipAngle: return "DipAngle";
113 case kCosThetaStar: return "CosThetaStar";
114 case kAngleLeading: return "AngleToLeading";
115 case kFirstDaughterPt: return "FirstDaughterPt";
116 case kSecondDaughterPt: return "SecondDaughterPt";
117 case kFirstDaughterP: return "FirstDaughterP";
118 case kSecondDaughterP: return "SecondDaughterP";
119 default: return "Undefined";
123 //_____________________________________________________________________________
124 Float_t AliRsnMiniValue::Eval(AliRsnMiniPair *pair, AliRsnMiniEvent *event)
127 // Evaluation of the required value.
128 // In this implementation, fills the member 4-vectors with data
129 // coming from the object passed as argument, and then returns the value
132 if (!pair && fType > kEventCuts) {
133 AliError("Null pair passed!");
137 // compute value depending on types in the enumeration
138 // if the type does not match any available choice, or if
139 // the computation is not doable due to any problem
140 // (not initialized support object, wrong values, risk of floating point errors)
141 // the method returng kFALSE and sets the computed value to a meaningless number
142 Double_t p3[3]= {0.,0.,0.};
143 AliRsnMiniParticle *l;
146 // ---- event values -------------------------------------------------------------------------
150 return event->Mult();
152 return event->Angle();
154 l = event->LeadingParticle();
156 l->Set4Vector(v,-1.0,fUseMCInfo);
161 return pair->Pt(fUseMCInfo);
163 return pair->InvMass(fUseMCInfo);
165 return pair->Eta(fUseMCInfo);
167 return pair->InvMassRes();
169 return pair->InvMassDiff();
171 return pair->Mt(fUseMCInfo);
173 return pair->Y(fUseMCInfo);
175 return pair->PtRatio(fUseMCInfo);
177 return pair->DipAngle(fUseMCInfo);
179 return pair->CosThetaStar(fUseMCInfo);
181 l = event->LeadingParticle();
183 l->Set4Vector(v,-1.0,fUseMCInfo);
184 Double_t angle = v.Phi() - pair->Sum(fUseMCInfo).Phi();
186 //return angle w.r.t. leading particle in the range -pi/2, 3/2pi
187 while (angle >= 1.5 * TMath::Pi()) angle -= 2 * TMath::Pi();
188 while (angle < -0.5 * TMath::Pi()) angle += 2 * TMath::Pi();
191 // AliWarning("This method is not yet implemented");
193 case kFirstDaughterPt:
194 return pair->DaughterPt(0,fUseMCInfo);
195 case kSecondDaughterPt:
196 return pair->DaughterPt(1,fUseMCInfo);
197 case kFirstDaughterP:
198 pair->DaughterPxPyPz(0,fUseMCInfo, p3);
199 return TMath::Sqrt(p3[0]*p3[0]+p3[1]*p3[1]+p3[2]*p3[2]);
200 case kSecondDaughterP:
201 pair->DaughterPxPyPz(1,fUseMCInfo, p3);
202 return TMath::Sqrt(p3[0]*p3[0]+p3[1]*p3[1]+p3[2]*p3[2]);
204 AliError("Invalid value type");