]>
Commit | Line | Data |
---|---|---|
ffb1ee30 | 1 | /************************************************************************** |
2 | * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * | |
3 | * * | |
4 | * Author: The ALICE Off-line Project. * | |
5 | * Contributors are mentioned in the code where appropriate. * | |
6 | * * | |
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 | **************************************************************************/ | |
15 | // | |
16 | // PID Response class for the TRD detector | |
17 | // Based on 1D Likelihood approach | |
18 | // Calculation of probabilities using Bayesian approach | |
19 | // Attention: This method is only used to separate electrons from pions | |
20 | // | |
21 | // Authors: | |
22 | // Markus Fasel <M.Fasel@gsi.de> | |
23 | // Anton Andronic <A.Andronic@gsi.de> | |
24 | // | |
25 | #include <TClass.h> | |
26 | #include <TAxis.h> | |
27 | #include <TFile.h> | |
28 | #include <TH1.h> | |
ce5d6908 | 29 | #include <TKey.h> |
ffb1ee30 | 30 | #include <TObjArray.h> |
31 | #include <TString.h> | |
ce5d6908 | 32 | #include <TROOT.h> |
ffb1ee30 | 33 | #include <TSystem.h> |
2ad33025 | 34 | #include <TDirectory.h> |
ffb1ee30 | 35 | |
36 | #include "AliLog.h" | |
37 | ||
51a0ce25 | 38 | #include "AliTRDPIDReference.h" |
ffb1ee30 | 39 | #include "AliTRDPIDResponse.h" |
40 | ||
41 | ClassImp(AliTRDPIDResponse) | |
42 | ||
ffb1ee30 | 43 | //____________________________________________________________ |
e0de37e9 | 44 | AliTRDPIDResponse::AliTRDPIDResponse(): |
45 | TObject() | |
51a0ce25 | 46 | ,fkPIDReference(NULL) |
e0de37e9 | 47 | ,fGainNormalisationFactor(1.) |
48 | ,fPIDmethod(kLQ1D) | |
ffb1ee30 | 49 | { |
e0de37e9 | 50 | // |
51 | // Default constructor | |
52 | // | |
ffb1ee30 | 53 | } |
54 | ||
55 | //____________________________________________________________ | |
56 | AliTRDPIDResponse::AliTRDPIDResponse(const AliTRDPIDResponse &ref): | |
e0de37e9 | 57 | TObject(ref) |
51a0ce25 | 58 | ,fkPIDReference(ref.fkPIDReference) |
e0de37e9 | 59 | ,fGainNormalisationFactor(ref.fGainNormalisationFactor) |
60 | ,fPIDmethod(ref.fPIDmethod) | |
ffb1ee30 | 61 | { |
e0de37e9 | 62 | // |
63 | // Copy constructor | |
e0de37e9 | 64 | // |
ffb1ee30 | 65 | } |
66 | ||
67 | //____________________________________________________________ | |
68 | AliTRDPIDResponse &AliTRDPIDResponse::operator=(const AliTRDPIDResponse &ref){ | |
e0de37e9 | 69 | // |
70 | // Assignment operator | |
e0de37e9 | 71 | // |
72 | if(this == &ref) return *this; | |
73 | ||
74 | // Make copy | |
75 | TObject::operator=(ref); | |
51a0ce25 | 76 | fGainNormalisationFactor = ref.fGainNormalisationFactor; |
77 | fkPIDReference = ref.fkPIDReference; | |
e0de37e9 | 78 | fPIDmethod = ref.fPIDmethod; |
79 | ||
80 | return *this; | |
ffb1ee30 | 81 | } |
82 | ||
83 | //____________________________________________________________ | |
84 | AliTRDPIDResponse::~AliTRDPIDResponse(){ | |
e0de37e9 | 85 | // |
86 | // Destructor | |
87 | // | |
51a0ce25 | 88 | if(IsOwner()) delete fkPIDReference; |
ffb1ee30 | 89 | } |
90 | ||
91 | //____________________________________________________________ | |
51a0ce25 | 92 | Bool_t AliTRDPIDResponse::Load(const Char_t * filename, const Char_t *refName){ |
e0de37e9 | 93 | // |
94 | // Load References into the toolkit | |
95 | // | |
96 | AliDebug(1, "Loading reference histos from root file"); | |
2ad33025 | 97 | TDirectory *owd = gDirectory;// store old working directory |
e0de37e9 | 98 | |
99 | if(!filename) | |
100 | filename = Form("%s/STEER/LQ1dRef_v1.root",gSystem->ExpandPathName("$ALICE_ROOT")); | |
101 | TFile *in = TFile::Open(filename); | |
102 | if(!in){ | |
103 | AliError("Ref file not available."); | |
104 | return kFALSE; | |
105 | } | |
106 | ||
107 | gROOT->cd(); | |
51a0ce25 | 108 | fkPIDReference = dynamic_cast<const AliTRDPIDReference *>(in->Get(refName)->Clone()); |
109 | in->Close(); delete in; | |
e0de37e9 | 110 | owd->cd(); |
e0de37e9 | 111 | SetBit(kIsOwner, kTRUE); |
51a0ce25 | 112 | AliDebug(2, Form("Successfully loaded References for %d Momentum bins", fkPIDReference->GetNumberOfMomentumBins())); |
e0de37e9 | 113 | return kTRUE; |
ffb1ee30 | 114 | } |
115 | ||
116 | //____________________________________________________________ | |
51a0ce25 | 117 | Bool_t AliTRDPIDResponse::GetResponse(Int_t n, const Double_t * const dedx, const Float_t * const p, Double_t prob[AliPID::kSPECIES], Bool_t kNorm) const |
ffb1ee30 | 118 | { |
e0de37e9 | 119 | // |
120 | // Calculate TRD likelihood values for the track based on dedx and | |
121 | // momentum values. The likelihoods are calculated by query the | |
122 | // reference data depending on the PID method selected | |
123 | // | |
124 | // Input parameter : | |
125 | // n - number of dedx slices/chamber | |
126 | // dedx - array of dedx slices organized layer wise | |
127 | // p - array of momentum measurements organized layer wise | |
128 | // | |
129 | // Return parameters | |
130 | // prob - probabilities allocated by TRD for particle specis | |
131 | // kNorm - switch to normalize probabilities to 1. By default true. If false return not normalized prob. | |
132 | // | |
133 | // Return value | |
134 | // true if calculation success | |
135 | // | |
ffb1ee30 | 136 | |
51a0ce25 | 137 | if(!fkPIDReference){ |
e0de37e9 | 138 | AliWarning("Missing reference data. PID calculation not possible."); |
139 | return kFALSE; | |
140 | } | |
ffb1ee30 | 141 | |
e0de37e9 | 142 | for(Int_t is(AliPID::kSPECIES); is--;) prob[is]=.2; |
143 | Double_t prLayer[AliPID::kSPECIES]; | |
51a0ce25 | 144 | Double_t dE[10], s(0.); |
e0de37e9 | 145 | for(Int_t il(kNlayer); il--;){ |
146 | memset(prLayer, 0, AliPID::kSPECIES*sizeof(Double_t)); | |
51a0ce25 | 147 | if(!CookdEdx(n, &dedx[il*n], &dE[0])) continue; |
ffb1ee30 | 148 | |
e0de37e9 | 149 | s=0.; |
150 | for(Int_t is(AliPID::kSPECIES); is--;){ | |
51a0ce25 | 151 | if((dE[0] > 0.) && (p[il] > 0.)) prLayer[is] = GetProbabilitySingleLayer(is, p[il], dE[0]); |
e0de37e9 | 152 | AliDebug(3, Form("Probability for Species %d in Layer %d: %f", is, il, prLayer[is])); |
153 | s+=prLayer[is]; | |
154 | } | |
155 | if(s<1.e-30){ | |
156 | AliDebug(2, Form("Null all species prob layer[%d].", il)); | |
157 | continue; | |
158 | } | |
159 | for(Int_t is(AliPID::kSPECIES); is--;){ | |
160 | if(kNorm) prLayer[is] /= s; | |
161 | prob[is] *= prLayer[is]; | |
162 | } | |
163 | } | |
164 | if(!kNorm) return kTRUE; | |
ffb1ee30 | 165 | |
e0de37e9 | 166 | s=0.; |
167 | for(Int_t is(AliPID::kSPECIES); is--;) s+=prob[is]; | |
168 | if(s<1.e-30){ | |
169 | AliDebug(2, "Null total prob."); | |
170 | return kFALSE; | |
171 | } | |
172 | for(Int_t is(AliPID::kSPECIES); is--;) prob[is]/=s; | |
173 | return kTRUE; | |
ffb1ee30 | 174 | } |
175 | ||
ffb1ee30 | 176 | //____________________________________________________________ |
b439f460 | 177 | Double_t AliTRDPIDResponse::GetProbabilitySingleLayer(Int_t species, Double_t plocal, Double_t dEdx) const { |
e0de37e9 | 178 | // |
179 | // Get the non-normalized probability for a certain particle species as coming | |
180 | // from the reference histogram | |
181 | // Interpolation between momentum bins | |
182 | // | |
183 | AliDebug(1, Form("Make Probability for Species %d with Momentum %f", species, plocal)); | |
51a0ce25 | 184 | Float_t pLower, pUpper; |
185 | Double_t probLayer = 0.; | |
186 | TH1 *refUpper = dynamic_cast<TH1 *>(fkPIDReference->GetUpperReference((AliPID::EParticleType)species, plocal, pUpper)), | |
187 | *refLower = dynamic_cast<TH1 *>(fkPIDReference->GetLowerReference((AliPID::EParticleType)species, plocal, pLower)); | |
e0de37e9 | 188 | // Do Interpolation exept for underflow and overflow |
51a0ce25 | 189 | if(refLower && refUpper){ |
190 | Double_t probLower = refLower->GetBinContent(refLower->GetXaxis()->FindBin(dEdx)); | |
191 | Double_t probUpper = refUpper->GetBinContent(refUpper->GetXaxis()->FindBin(dEdx)); | |
e0de37e9 | 192 | |
51a0ce25 | 193 | probLayer = probLower + (probUpper - probLower)/(pUpper-pLower) * (plocal - pLower); |
194 | } else if(refLower){ | |
195 | // underflow | |
196 | probLayer = refLower->GetBinContent(refLower->GetXaxis()->FindBin(dEdx)); | |
197 | } else if(refUpper){ | |
198 | // overflow | |
199 | probLayer = refUpper->GetBinContent(refUpper->GetXaxis()->FindBin(dEdx)); | |
200 | } else { | |
201 | AliError("No references available"); | |
e0de37e9 | 202 | } |
51a0ce25 | 203 | AliDebug(1, Form("Probability %f", probLayer)); |
204 | return probLayer; | |
ffb1ee30 | 205 | } |
206 | ||
207 | //____________________________________________________________ | |
208 | void AliTRDPIDResponse::SetOwner(){ | |
e0de37e9 | 209 | // |
210 | // Make Deep Copy of the Reference Histograms | |
211 | // | |
51a0ce25 | 212 | if(!fkPIDReference || IsOwner()) return; |
213 | const AliTRDPIDReference *tmp = fkPIDReference; | |
214 | fkPIDReference = dynamic_cast<const AliTRDPIDReference *>(tmp->Clone()); | |
e0de37e9 | 215 | SetBit(kIsOwner, kTRUE); |
ffb1ee30 | 216 | } |
217 | ||
218 | //____________________________________________________________ | |
51a0ce25 | 219 | Bool_t AliTRDPIDResponse::CookdEdx(Int_t nSlice, const Double_t * const in, Double_t *out) const |
ffb1ee30 | 220 | { |
51a0ce25 | 221 | // |
222 | // Recalculate dE/dx | |
223 | // | |
e0de37e9 | 224 | switch(fPIDmethod){ |
225 | case kNN: // NN | |
226 | break; | |
227 | case kLQ2D: // 2D LQ | |
228 | break; | |
229 | case kLQ1D: // 1D LQ | |
230 | out[0]= 0.; | |
231 | for(Int_t islice = 0; islice < nSlice; islice++) out[0] += in[islice] * fGainNormalisationFactor; | |
232 | if(out[0] < 1e-6) return kFALSE; | |
233 | break; | |
234 | default: | |
235 | return kFALSE; | |
236 | } | |
237 | return kTRUE; | |
ffb1ee30 | 238 | } |
239 |