HLT/global/AliHLTV0FinderComponent.cxx

   1 // $Id$
   2
   3 //**************************************************************************
   4 //* This file is property of and copyright by the ALICE HLT Project        *
   5 //* ALICE Experiment at CERN, All rights reserved.                         *
   6 //*                                                                        *
   7 //* Primary Authors: Timur Pocheptsov <Timur.Pocheptsov@cern.ch>           *
   8 //*                  for The ALICE HLT Project.                            *
   9 //*                                                                        *
  10 //* Permission to use, copy, modify and distribute this software and its   *
  11 //* documentation strictly for non-commercial purposes is hereby granted   *
  12 //* without fee, provided that the above copyright notice appears in all   *
  13 //* copies and that both the copyright notice and this permission notice   *
  14 //* appear in the supporting documentation. The authors make no claims     *
  15 //* about the suitability of this software for any purpose. It is          *
  16 //* provided "as is" without express or implied warranty.                  *
  17 //**************************************************************************
  18
  19 /// @file   AliHLTV0FinderComponent.cxx
  20 /// @author Timur Pocheptsov
  21 /// @date   2010-12-26
  22 /// @brief  V0 finder component
  23 ///
  24
  25 #include "TString.h"
  26
  27 #include "AliHLTDataTypes.h"
  28 #include "AliHLTV0FinderComponent.h"
  29
  30 ClassImp(AliHLTV0FinderComponent)
  31
  32 const double AliHLTV0FinderComponent::fgDaughterPrimDeviation = 2.5;
  33 const double AliHLTV0FinderComponent::fgPrimDeviation = 3.5;
  34 const double AliHLTV0FinderComponent::fgChi = 3.5;
  35 const double AliHLTV0FinderComponent::fgDecayLengthInSigmas = 3.;
  36
  37 //________________________________________________________________________
  38 AliHLTV0FinderComponent::AliHLTV0FinderComponent()
  39                   : fPrimaryVtx(),
  40                     fPrimaryTracks(),
  41                     fNPrimaryTracks(0),
  42                     fMinPrimID(0),
  43                     fMaxPrimID(0),
  44                     fDaughterPrimDeviation(fgDaughterPrimDeviation),
  45                     fPrimDeviation(fgPrimDeviation),
  46                     fChi(fgChi),
  47                     fDecayLengthInSigmas(fgDecayLengthInSigmas),
  48                     fPosPID(211),
  49                     fNegPID(211),
  50                     fV0s(),
  51                     fGammaFinder(false)
  52 {
  53   //Default ctor.
  54 }
  55
  56 //________________________________________________________________________
  57 const char* AliHLTV0FinderComponent::GetComponentID()
  58 {
  59   //Component's "name".
  60   return "V0Finder";
  61 }
  62
  63 //________________________________________________________________________
  64 void AliHLTV0FinderComponent::GetInputDataTypes(AliHLTComponentDataTypeList& list)
  65 {
  66   //Input to the primary vertex finder:
  67   //a)tracks from ESD object;
  68   //b)hlt tracks (ITS)
  69   //c)hlt tracks (TPC)
  70   //d)primary vertex (AliKFVertex)
  71   //e)indices of primary tracks.
  72   list.clear();
  73   //Input tracks.
  74   list.push_back(kAliHLTDataTypeESDObject);
  75   list.push_back(kAliHLTDataTypeTrack | kAliHLTDataOriginITS);
  76   list.push_back(kAliHLTDataTypeTrack | kAliHLTDataOriginTPC);
  77   //Input from primary finder:
  78   //Primary vertex.
  79   list.push_back(kAliHLTDataTypeKFVertex | kAliHLTDataOriginOut);
  80   //Primary tracks' indices.
  81   list.push_back(kAliHLTDataTypePrimaryFinder | kAliHLTDataOriginOut);
  82 }
  83
  84 //________________________________________________________________________
  85 AliHLTComponentDataType AliHLTV0FinderComponent::GetOutputDataType()
  86 {
  87   //Data type of output.
  88   return kAliHLTMultipleDataType;
  89 }
  90
  91 //________________________________________________________________________
  92 int AliHLTV0FinderComponent::GetOutputDataTypes(AliHLTComponentDataTypeList& tgtList)
  93 {
  94   //Output type for V0 finder.
  95   tgtList.clear();
  96   //Indices of tracks, participating in V0s.
  97   tgtList.push_back(kAliHLTDataTypeV0Finder | kAliHLTDataOriginOut);
  98
  99   return tgtList.size();
 100 }
 101
 102 //________________________________________________________________________
 103 void AliHLTV0FinderComponent::GetOutputDataSize(unsigned long& constBase, double& inputMultiplier)
 104 {
 105   //These numbers are complete crap.
 106   constBase = 80000;
 107   inputMultiplier = 2.;
 108 }
 109
 110 //________________________________________________________________________
 111 AliHLTComponent* AliHLTV0FinderComponent::Spawn()
 112 {
 113   //Create primary vertex finder componet.
 114   return new AliHLTV0FinderComponent;
 115 }
 116
 117 //________________________________________________________________________
 118 int AliHLTV0FinderComponent::DoInit(int argc, const char** argv)
 119 {
 120   //1. Default parameters.
 121   fDaughterPrimDeviation = fgDaughterPrimDeviation;
 122   fPrimDeviation = fgPrimDeviation;
 123   fChi = fgChi;
 124   fDecayLengthInSigmas = fgDecayLengthInSigmas;
 125   fPosPID = 211;
 126   fNegPID = 211;
 127   fGammaFinder = false;
 128
 129   //2. Parameters from OCDB.
 130   TString cdbPath("HLT/ConfigHLT/");
 131   cdbPath += GetComponentID();
 132
 133   int res = ConfigureFromCDBTObjString(cdbPath);
 134   if (res < 0)
 135     return res;
 136
 137   //3. "Command line" parameters.
 138   if (argc)
 139     res = ConfigureFromArgumentString(argc, argv);
 140
 141   return res;
 142 }
 143
 144 //________________________________________________________________________
 145 int AliHLTV0FinderComponent::ScanConfigurationArgument(int argc, const char** argv)
 146 {
 147   //Scan one argument and its parameters from the list
 148   //Return number of processed entries.
 149   //Possible arguments:
 150   //-daughterPrimDeviation num
 151   //-primDeviation num
 152   //-chi num
 153   //-decayLengthInSigmas num
 154   //-posPID int_num
 155   //-negPid int_num
 156   //-gammaFinder 0/1
 157
 158   AliHLTUtility::CmdLineParser parser;
 159   parser.Add("-daughterPrimDeviation", &fDaughterPrimDeviation);
 160   parser.Add("-primDeviation", &fPrimDeviation);
 161   parser.Add("-chi", &fChi);
 162   parser.Add("-decayLengthInSigmas", &fDecayLengthInSigmas);
 163   parser.Add("-posPID", &fPosPID);
 164   parser.Add("-negPID", &fNegPID);
 165   parser.Add("-gammaFinder", &fGammaFinder);
 166
 167   const int nParsed = parser.Parse(argc, argv, 0);
 168   if (nParsed < 0) {
 169     HLTError(parser.GetError().Data());
 170     return -EPROTO;
 171   }
 172
 173   return nParsed;
 174 }
 175
 176 //________________________________________________________________________
 177 int AliHLTV0FinderComponent::DoDeinit()
 178 {
 179   //Reset parameters to default.
 180   fDaughterPrimDeviation = fgDaughterPrimDeviation;
 181   fPrimDeviation = fgPrimDeviation;
 182   fChi = fgChi;
 183   fDecayLengthInSigmas = fgDecayLengthInSigmas;
 184   fPosPID = 211;
 185   fNegPID = 211;
 186   fGammaFinder = false;
 187
 188   return 0;
 189 }
 190
 191 //________________________________________________________________________
 192 int AliHLTV0FinderComponent::DoEvent(const AliHLTComponentEventData& /*evtData*/,
 193                             AliHLTComponentTriggerData& /*trigData*/)
 194 {
 195   //Find primary vertex.
 196   if (GetFirstInputBlock(kAliHLTDataTypeSOR) || GetFirstInputBlock(kAliHLTDataTypeEOR))
 197     return 0;
 198
 199   //Clean all previous track infos.
 200   fTrackInfos.clear();
 201   fPrimaryTracks.clear();
 202
 203   //Initialize KF package.
 204   AliKFParticle::SetField(GetBz());
 205
 206   if (!ReadPrimaryVertex())
 207     return 0;
 208
 209   if (!ReadTracks())
 210     return 0;
 211
 212   FindV0s();
 213
 214   return DoOutput();
 215 }
 216
 217 //________________________________________________________________________
 218 bool AliHLTV0FinderComponent::ReadPrimaryVertex()
 219 {
 220   //Primary finder produces primary vertex (AliKFVertex) and
 221   //indices for primary tracks.
 222   //1. Try to extract primary vertex.
 223   const TObject* obj = GetFirstInputObject(kAliHLTDataTypeKFVertex | kAliHLTDataOriginOut);
 224   const AliKFVertex* kfVtx = dynamic_cast<const AliKFVertex*>(obj);
 225
 226   if (!kfVtx) {
 227     HLTError("V0 finder requires KF vertex (primary vertex) as input");
 228     return false;
 229   }
 230
 231   //2. Try to read primary track indices.
 232   const AliHLTComponentBlockData* p = GetFirstInputBlock(kAliHLTDataTypePrimaryFinder
 233                                                           | kAliHLTDataOriginOut);
 234   if (!p || !p->fSize || !p->fPtr) {
 235     HLTError("Array of primary track indices expected");
 236     return false;
 237   }
 238
 239   //Data block from primary finder
 240   const PrimaryFinderBlock* blk = static_cast<PrimaryFinderBlock*>(p->fPtr);
 241   //Track ids must be positive integers.
 242   if (blk->fMinPrimID < 0 || blk->fMaxPrimID < 0) {
 243     HLTError("Got negative track ID from primary finder, internal HLT error");
 244     return false;
 245   }
 246
 247   //3. Got correct data, modify the component's state.
 248   //KF vertex.
 249   fPrimaryVtx = *kfVtx;
 250   //Primary tracks.
 251   fNPrimaryTracks = blk->fNPrimaryTracks;
 252   fMinPrimID = blk->fMinPrimID;
 253   fMaxPrimID = blk->fMaxPrimID;
 254
 255   fPrimaryTracks.assign(fMaxPrimID + 1, 0);
 256   for (int i = 0; i < fNPrimaryTracks; ++i)
 257     fPrimaryTracks[blk->fPrimTrackIds[i]] = 1;
 258
 259   return true;
 260 }
 261
 262 //________________________________________________________________________
 263 bool AliHLTV0FinderComponent::ReadTracks()
 264 {
 265   //The logic, how vertex finder reads input tracks,
 266   //is taken from the original global vertexer.
 267   //First, try to read tracks from ESD event.
 268   ReadESDTracks(fPosPID, fNegPID);
 269   if (fTrackInfos.size()) {
 270     FindPrimaryDeviations();
 271     return true;
 272   }
 273
 274   //No good esd tracks, try:
 275   ReadHLTTracks(kAliHLTDataTypeTrack | kAliHLTDataOriginITS, fPosPID, fNegPID);
 276   if (fTrackInfos.size()) {
 277     FindPrimaryDeviations();
 278     return true;
 279   }
 280
 281   //If no good its tracks, try:
 282   ReadHLTTracks(kAliHLTDataTypeTrack | kAliHLTDataOriginTPC, fPosPID, fNegPID);
 283   if (fTrackInfos.size()) {
 284     FindPrimaryDeviations();
 285     return true;
 286   }
 287
 288   HLTError("No input tracks found for V0 finder");
 289
 290   return false;
 291 }
 292
 293 //________________________________________________________________________
 294 void AliHLTV0FinderComponent::FindPrimaryDeviations()
 295 {
 296   //Quite a tricky part.
 297   for (VectorSize_t i = 0; i < fTrackInfos.size(); ++i) {
 298     AliHLTTrackInfo& info = fTrackInfos[i];
 299     if (IsPrimaryTrack(info.fID)) {
 300       info.fPrimUsed = true;
 301       //The way primary deviation is computed in primary finder:
 302       if (fNPrimaryTracks <= 20) {
 303         AliKFVertex tmp(fPrimaryVtx - info.fParticle);
 304         info.fPrimDeviation = info.fParticle.GetDeviationFromVertex(tmp);
 305       } else
 306         info.fPrimDeviation = info.fParticle.GetDeviationFromVertex(fPrimaryVtx);
 307     } else {
 308       info.fPrimUsed = false;
 309       info.fPrimDeviation = info.fParticle.GetDeviationFromVertex(fPrimaryVtx);
 310     }
 311   }
 312 }
 313
 314 //________________________________________________________________________
 315 bool AliHLTV0FinderComponent::IsPrimaryTrack(int id)const
 316 {
 317   if (id < fMinPrimID || id > fMaxPrimID)
 318     return false;
 319
 320   return fPrimaryTracks[id];
 321 }
 322
 323 //________________________________________________________________________
 324 void AliHLTV0FinderComponent::FindV0s()
 325 {
 326   //Here's the core.
 327   if (fPrimaryVtx.GetNContributors() < 3)
 328     return;
 329
 330   fV0s.clear();
 331   fV0s.push_back(0); //Number of v0s.
 332
 333   for (int iTr = 0, ei = fTrackInfos.size(); iTr < ei; ++iTr) {
 334     AliHLTTrackInfo& info = fTrackInfos[iTr];
 335     if (info.fParticle.GetQ() > 0)
 336       continue;
 337     if (info.fPrimDeviation < fDaughterPrimDeviation)
 338       continue;
 339
 340     for (int jTr = 0; jTr < ei; ++jTr) {
 341       AliHLTTrackInfo& jnfo = fTrackInfos[jTr];
 342       if (jnfo.fParticle.GetQ() < 0)
 343         continue;
 344       if (jnfo.fPrimDeviation < fDaughterPrimDeviation)
 345         continue;
 346
 347       //Check if the particles fit
 348       if (info.fParticle.GetDeviationFromParticle(jnfo.fParticle) > fChi)
 349         continue;
 350
 351       //Construct V0 mother
 352       AliKFParticle v0(info.fParticle, jnfo.fParticle /*, bGammaFinder*/);
 353       //Check V0 Chi^2
 354       if (v0.GetChi2() < 0. || v0.GetChi2() > fChi * fChi * v0.GetNDF())
 355         continue;
 356
 357       //Subtruct daughters from primary vertex
 358       AliKFVertex primVtxCopy(fPrimaryVtx);
 359
 360       if (info.fPrimUsed) {
 361         if (primVtxCopy.GetNContributors() <= 2)
 362           continue;
 363         primVtxCopy -= info.fParticle;
 364       }
 365
 366       if (jnfo.fPrimUsed) {
 367         if (primVtxCopy.GetNContributors() <= 2)
 368           continue;
 369         primVtxCopy -= jnfo.fParticle;
 370       }
 371
 372       //Check v0 Chi^2 deviation from primary vertex
 373       if (v0.GetDeviationFromVertex(primVtxCopy) > fPrimDeviation)
 374         continue;
 375       //Add V0 to primary vertex to improve the primary vertex resolution
 376       primVtxCopy += v0;
 377       //Set production vertex for V0
 378       v0.SetProductionVertex(primVtxCopy);
 379       //Get V0 decay length with estimated error
 380       double length = 0., sigmaLength = 0.;
 381       if (v0.GetDecayLength(length, sigmaLength))
 382         continue;
 383       //Reject V0 if it decays too close[sigma] to the primary vertex
 384       if (length  < fDecayLengthInSigmas * sigmaLength)
 385         continue;
 386       //Keep v0
 387       fV0s.push_back(info.fID);
 388       fV0s.push_back(jnfo.fID);
 389
 390       fV0s[0] += 1;
 391     }
 392   }
 393 }
 394
 395 //________________________________________________________________________
 396 int AliHLTV0FinderComponent::DoOutput()
 397 {
 398   //Save V0s' track pairs' indices.
 399   if (!fV0s.size() || !fV0s[0]) {
 400     HLTInfo("No v0s were found");
 401     return 0;
 402   }
 403
 404   //Indices of primary tracks.
 405   return PushBack(&fV0s[0], fV0s.size() * sizeof(int),
 406                   kAliHLTDataTypeV0Finder | kAliHLTDataOriginOut);
 407 }