Be sure to load mapping when needed
[u/mrichter/AliRoot.git] / TRD / AliTRDpidESD.cxx
index fb255d8..705103a 100644 (file)
@@ -1,17 +1,17 @@
 /**************************************************************************
- * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
- *                                                                        *
- * Author: The ALICE Off-line Project.                                    *
- * Contributors are mentioned in the code where appropriate.              *
- *                                                                        *
- * Permission to use, copy, modify and distribute this software and its   *
- * documentation strictly for non-commercial purposes is hereby granted   *
- * without fee, provided that the above copyright notice appears in all   *
- * copies and that both the copyright notice and this permission notice   *
- * appear in the supporting documentation. The authors make no claims     *
- * about the suitability of this software for any purpose. It is          *
- * provided "as is" without express or implied warranty.                  *
- **************************************************************************/
+* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
+*                                                                        *
+* Author: The ALICE Off-line Project.                                    *
+* Contributors are mentioned in the code where appropriate.              *
+*                                                                        *
+* Permission to use, copy, modify and distribute this software and its   *
+* documentation strictly for non-commercial purposes is hereby granted   *
+* without fee, provided that the above copyright notice appears in all   *
+* copies and that both the copyright notice and this permission notice   *
+* appear in the supporting documentation. The authors make no claims     *
+* about the suitability of this software for any purpose. It is          *
+* provided "as is" without express or implied warranty.                  *
+**************************************************************************/
 
 /* $Id$ */
 
 // Implementation of the TRD PID class                                    //
 //                                                                        //
 // Assigns the electron and pion likelihoods to each ESD track.           //
-// The function MakePID(AliESD *event) calculates the probability         //
+// The function MakePID(AliESDEvent *event) calculates the probability    //
 // of having dedx and a maximum timbin at a given                         //
 // momentum (mom) and particle type k                                     //
 // from the precalculated distributions.                                  //
 //                                                                        //
 // Authors :                                                              //
-// Prashant Shukla <shukla@pi0.physi.uni-heidelberg.de> (Original version)//
-// Alex Bercuci (a.bercuci@gsi.de)                                        //
+//   Prashant Shukla <shukla@pi0.physi.uni-heidelberg.de> (orig. version) //
+//   Alex Bercuci (a.bercuci@gsi.de)                                      //
 //                                                                        //
 ////////////////////////////////////////////////////////////////////////////
 
-#include "AliLog.h"
-#include "AliESD.h"
+#include "AliESDEvent.h"
 #include "AliESDtrack.h"
+#include "AliTracker.h"
 
 #include "AliTRDpidESD.h"
 #include "AliTRDgeometry.h"
 #include "AliTRDcalibDB.h"
-#include "AliRun.h"
-#include "AliTRDtrack.h"
-#include "Cal/AliTRDCalPIDLQ.h"
+#include "Cal/AliTRDCalPID.h"
 
 ClassImp(AliTRDpidESD)
 
-  Bool_t AliTRDpidESD::fCheckTrackStatus = kTRUE;
-  Bool_t AliTRDpidESD::fCheckKinkStatus  = kFALSE;
-  Int_t AliTRDpidESD::fMinPlane          = 0;
+Bool_t  AliTRDpidESD::fgCheckTrackStatus = kTRUE;
+Bool_t  AliTRDpidESD::fgCheckKinkStatus  = kFALSE;
+Int_t   AliTRDpidESD::fgMinPlane         = 0;
 
 //_____________________________________________________________________________
 AliTRDpidESD::AliTRDpidESD()
   :TObject()
+  ,fTrack(NULL)
 {
   //
   // Default constructor
@@ -61,6 +60,7 @@ AliTRDpidESD::AliTRDpidESD()
 //_____________________________________________________________________________
 AliTRDpidESD::AliTRDpidESD(const AliTRDpidESD &p)
   :TObject(p)
+  ,fTrack(NULL)
 {
   //
   // AliTRDpidESD copy constructor
@@ -71,6 +71,17 @@ AliTRDpidESD::AliTRDpidESD(const AliTRDpidESD &p)
 }
 
 //_____________________________________________________________________________
+AliTRDpidESD::~AliTRDpidESD()
+{
+  //
+  // Destructor
+  //
+
+  if(fTrack) delete fTrack;
+
+}
+
+//_____________________________________________________________________________
 AliTRDpidESD &AliTRDpidESD::operator=(const AliTRDpidESD &p)
 {
   //
@@ -89,14 +100,15 @@ void AliTRDpidESD::Copy(TObject &p) const
   // Copy function
   //
 
-  ((AliTRDpidESD &) p).fCheckTrackStatus          = fCheckTrackStatus;
-  ((AliTRDpidESD &) p).fCheckKinkStatus           = fCheckKinkStatus;
-  ((AliTRDpidESD &) p).fMinPlane                  = fMinPlane;
-
+  ((AliTRDpidESD &) p).fgCheckTrackStatus         = fgCheckTrackStatus;
+  ((AliTRDpidESD &) p).fgCheckKinkStatus          = fgCheckKinkStatus;
+  ((AliTRDpidESD &) p).fgMinPlane                 = fgMinPlane;
+  ((AliTRDpidESD &) p).fTrack                     = NULL;
+  
 }
 
 //_____________________________________________________________________________
-Int_t AliTRDpidESD::MakePID(AliESD *event)
+Int_t AliTRDpidESD::MakePID(AliESDEvent * const event)
 {
   //
   // This function calculates the PID probabilities based on TRD signals
@@ -104,155 +116,186 @@ Int_t AliTRDpidESD::MakePID(AliESD *event)
   // The method produces probabilities based on the charge
   // and the position of the maximum time bin in each layer.
   // The dE/dx information can be used as global charge or 2 to 3
-  // slices. Check AliTRDCalPIDLQ and AliTRDCalPIDLQRef for the actual
+  // slices. Check AliTRDCalPID and AliTRDCalPIDRefMaker for the actual
   // implementation.
   //
   // Author
   // Alex Bercuci (A.Bercuci@gsi.de) 2nd May 2007
+  //
+
+  AliTRDcalibDB *calibration = AliTRDcalibDB::Instance();
+  if (!calibration) {
+    AliErrorGeneral("AliTRDpidESD::MakePID()"
+      ,"No access to calibration data");
+    return -1;
+  }
+  
+//   AliTRDrecoParam *rec = AliTRDReconstructor::RecoParam();
+//   if (!rec) {
+//     AliErrorGeneral("AliTRDpidESD::MakePID()", "No TRD reco param.");
+//     return 0x0;
+//   }
+
+  // Retrieve the CDB container class with the probability distributions
+  const AliTRDCalPID *pd = calibration->GetPIDObject(AliTRDpidUtil::kLQ);
+  if (!pd) {
+    AliErrorGeneral("AliTRDpidESD::MakePID()"
+      ,"No access to AliTRDCalPID");
+    return -1;
+  }
+
+  // Loop through all ESD tracks
+  Double_t p[10];
+  AliESDtrack *t = NULL;
+  Float_t dedx[AliTRDCalPID::kNSlicesLQ], dEdx;
+  Int_t   timebin;
+  Float_t mom, length;
+  Int_t   nPlanePID;
+  for (Int_t i=0; i<event->GetNumberOfTracks(); i++) {
+    t = event->GetTrack(i);
+    
+    // Check track
+    if(!CheckTrack(t)) continue;
+
+            
+    // Skip tracks which have no TRD signal at all
+    if (t->GetTRDsignal()<1.e-5) continue;
+  
+    // Loop over detector layers
+    mom          = 0.;
+    length       = 0.;
+    nPlanePID    = 0;
+    for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) 
+                  p[iSpecies] = 1./AliPID::kSPECIES;
+
+    for (Int_t iLayer = 0; iLayer < AliTRDgeometry::kNlayer; iLayer++) {
+      // read data for track segment
+      for(int iSlice=0; iSlice<AliTRDCalPID::kNSlicesLQ; iSlice++)
+        dedx[iSlice] = t->GetTRDslice(iLayer, iSlice);
+      dEdx    = t->GetTRDslice(iLayer, -1);
+      timebin = t->GetTRDTimBin(iLayer);
+
+      // check data
+      if ((dEdx <=  0.) || (timebin <= -1.)) continue;
+
+      // retrive kinematic info for this track segment
+      if(!RecalculateTrackSegmentKine(t, iLayer, mom, length)){
+        // information is not fully reliable especialy for length
+        // estimation. To be used in the future. 
+      }
+      
+      // this track segment has fulfilled all requierments
+      nPlanePID++;
+
+      // Get the probabilities for the different particle species
+      for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) {
+        p[iSpecies] *= pd->GetProbability(iSpecies, mom, dedx, length, iLayer);
+        //p[iSpecies] *= pd->GetProbabilityT(iSpecies, mom, timebin);
+      }
+    }
+    if(nPlanePID == 0) continue;
+    
+    // normalize probabilities
+    Double_t probTotal = 0.;
+    for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) probTotal   += p[iSpecies];
+    if(probTotal <= 0.){
+      AliWarning(Form("The total probability (%e) over all species <= 0 in ESD track %d."
+                                      , probTotal, i));
+      AliWarning("This may be caused by some error in reference data.");
+      AliWarning("Calculation continues but results might be corrupted.");
+      continue;
+    }
+    for(Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) p[iSpecies] /= probTotal;
+
+    // book PID to the track
+    t->SetTRDpid(p);
+    t->SetTRDntracklets(nPlanePID<<3);
+  }
+  
+  return 0;
 
-       AliTRDcalibDB *calibration = AliTRDcalibDB::Instance();
-       if (!calibration) {
-               AliErrorGeneral("AliTRDpidESD::MakePID()"
-                       ,"No access to calibration data");
-               return -1;
-       }
-       
-       // Retrieve the CDB container class with the probability distributions
-       const AliTRDCalPIDLQ *pd = calibration->GetPIDLQObject();
-       if (!pd) {
-               AliErrorGeneral("AliTRDpidESD::MakePID()"
-                       ,"No access to AliTRDCalPIDLQ");
-               return -1;
-       }
-
-
-       // Loop through all ESD tracks
-       Double_t p[10];
-       AliESDtrack *t = 0x0;
-       Double_t dedx[AliTRDtrack::kNslice], dEdx;
-       Int_t    timebin;
-       Float_t mom, length, probTotal;
-       Int_t nPlanePID;
-       for (Int_t i=0; i<event->GetNumberOfTracks(); i++) {
-               t = event->GetTrack(i);
-
-               // Check track
-               if(!CheckTrack(t)) continue;
-                                               
-               // Skip tracks which have no TRD signal at all
-               if (t->GetTRDsignal() == 0.) continue;
-       
-               // Loop over detector layers
-               mom       = 0.; //t->GetP();
-               length    = 0.;
-               probTotal = 0.;
-               nPlanePID    = 0;
-               for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) p[iSpecies] = 1.;
-               for (Int_t iPlan = 0; iPlan < AliTRDgeometry::kNplan; iPlan++) {
-                       // read data for track segment
-                       for(int iSlice=0; iSlice<AliTRDtrack::kNslice; iSlice++)
-                               dedx[iSlice] = t->GetTRDsignals(iPlan, iSlice);
-                       dEdx    = t->GetTRDsignals(iPlan, -1);
-                       timebin = t->GetTRDTimBin(iPlan);
-
-                       // check data
-                       if ((dEdx <=  0.) || (timebin <= -1.)) continue;
-
-                       // retrive kinematic info for this track segment
-                       if(!GetTrackSegmentKine(t, iPlan, mom, length)) continue;
-                       
-                       // this track segment has fulfilled all requierments
-                       nPlanePID++;
-                       
-                       // Get the probabilities for the different particle species
-                       for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++) {
-                               p[iSpecies] *= pd->GetProbability(iSpecies, mom, dedx, length);
-                               p[iSpecies] *= pd->GetProbabilityT(iSpecies, mom, timebin);
-                               probTotal   += p[iSpecies];
-                       }
-               }
-
-               // normalize probabilities
-               if(probTotal > 0.)
-                       for (Int_t iSpecies = 0; iSpecies < AliPID::kSPECIES; iSpecies++)
-                               if(nPlanePID > fMinPlane) p[iSpecies] /= probTotal;
-                               else p[iSpecies] = 1.0;
-
-
-               // book PID to the track
-               t->SetTRDpid(p);
-       }
-       
-       return 0;
 }
 
 //_____________________________________________________________________________
-Bool_t AliTRDpidESD::CheckTrack(AliESDtrack *t)
+Bool_t AliTRDpidESD::CheckTrack(AliESDtrack * const t)
 {
   //
   // Check if track is eligible for PID calculations
   //
-       
-       // Check the ESD track status
-       if (fCheckTrackStatus) {
-               if (((t->GetStatus() & AliESDtrack::kTRDout  ) == 0) &&
-                       ((t->GetStatus() & AliESDtrack::kTRDrefit) == 0)) return kFALSE;
-       }
+  
+  // Check the ESD track status
+  if (fgCheckTrackStatus) {
+    if (((t->GetStatus() & AliESDtrack::kTRDout  ) == 0) &&
+      ((t->GetStatus() & AliESDtrack::kTRDrefit) == 0)) return kFALSE;
+  }
 
-       // Check for ESD kink tracks
-       if (fCheckKinkStatus && (t->GetKinkIndex(0) != 0)) return kFALSE;
+  // Check for ESD kink tracks
+  if (fgCheckKinkStatus && (t->GetKinkIndex(0) != 0)) return kFALSE;
+
+  return kTRUE;
 
-       return kTRUE;
 }
 
 //_____________________________________________________________________________
-Bool_t AliTRDpidESD::GetTrackSegmentKine(AliESDtrack *t, Int_t plan, Float_t &mom, Float_t &length)
+Bool_t AliTRDpidESD::RecalculateTrackSegmentKine(AliESDtrack * const esd
+                                              , Int_t layer
+                                              , Float_t &mom
+                                              , Float_t &length)
 {
   //
   // Retrive momentum "mom" and track "length" in TRD chamber from plane
   // "plan" according to information stored in AliESDtrack "t".
-  // 
-
-       if(!gAlice){
-               AliErrorGeneral("AliTRDpidESD::GetTrackSegmentKine()"
-               ,"No gAlice object to retrive TRDgeometry and Magnetic fied  - this has to be removed in the future.");
-               return kFALSE;
-       }
-       
-       // Retrieve TRD geometry -> Maybe there is a better way to do this
-       AliTRDgeometry trdGeom;
-       const Float_t kAmHalfWidth = AliTRDgeometry::AmThick() / 2.;
+  //
+  // Origin
+  // Alex Bercuci (A.Bercuci@gsi.de)   
+  //
+
+  const Float_t kAmHalfWidth = AliTRDgeometry::AmThick() / 2.;
         const Float_t kDrWidth     = AliTRDgeometry::DrThick();
-       
-
-       // retrive the magnetic field
-       Double_t xyz0[3] = { 0., 0., 0.}, xyz1[3];
-       Double_t b[3], alpha;
-       gAlice->Field(xyz0,b);      // b[] is in kilo Gauss
-       Float_t field = b[2] * 0.1; // Tesla
-               
-       // find momentum at chamber entrance and track length in chamber
-       AliExternalTrackParam *param = (plan<3) ? new AliExternalTrackParam(*t->GetInnerParam()) : new AliExternalTrackParam(*t->GetOuterParam());
-
-       param->PropagateTo(trdGeom.GetTime0(plan)+kAmHalfWidth, field);
-       param->GetXYZ(xyz0);
-       alpha = param->GetAlpha();
-       param->PropagateTo(trdGeom.GetTime0(plan)-kAmHalfWidth-kDrWidth, field);
-       // eliminate track segments which are crossing SM boundaries along chamber
-       if(TMath::Abs(alpha-param->GetAlpha())>.01){
-               delete param;
-               return kFALSE;
-       }
-       param->GetXYZ(xyz1);
-       length = sqrt(
-               (xyz1[0]-xyz0[0])*(xyz1[0]-xyz0[0])+
-               (xyz1[1]-xyz0[1])*(xyz1[1]-xyz0[1])+
-               (xyz1[2]-xyz0[2])*(xyz1[2]-xyz0[2])
-       );
-       param->GetPxPyPz(xyz1);
-       mom = sqrt(xyz1[0]*xyz1[0] + xyz1[1]*xyz1[1] + xyz1[2]*xyz1[2]);
-       delete param;
-
-       return kTRUE;
-}
+  const Float_t kTime0       = AliTRDgeometry::GetTime0(layer);
+
+  // set initial length value to chamber height 
+  length = 2 * kAmHalfWidth + kDrWidth;
+    
+  // retrive track's outer param
+  const AliExternalTrackParam *op = esd->GetOuterParam();
+  if(!op){
+    mom    = esd->GetP();
+    return kFALSE;
+  }
+
+  AliExternalTrackParam *param = NULL;
+  if(!fTrack){
+    fTrack = new AliExternalTrackParam(*op);
+    param = fTrack;
+  } else param = new(fTrack) AliExternalTrackParam(*op);
+  
+  // retrive the magnetic field
+  Double_t xyz0[3];
+  op->GetXYZ(xyz0);
+  Float_t field = AliTracker::GetBz(xyz0); // Bz in kG at point xyz0
+  Double_t s, t;
+
+  // propagate to chamber entrance
+  if(!param->PropagateTo(kTime0-kAmHalfWidth-kDrWidth, field)){
+    mom    = op->GetP();
+    s      = op->GetSnp();
+    t      = op->GetTgl();
+    if (s < 1.) length /= TMath::Sqrt((1.-s)*(1.+s) / (1. + t*t));
+    return kFALSE;
+  }
+  mom        = param->GetP();
+  s = param->GetSnp();
+  t = param->GetTgl();
+  if (s < 1.) length    /= TMath::Sqrt((1.-s)*(1.+s) / (1. + t*t));
+
+  // check if track is crossing tracking sector by propagating to chamber exit- maybe is too much :)
+  Double_t alpha = param->GetAlpha();
+  if(!param->PropagateTo(kTime0+kAmHalfWidth, field)) return kFALSE;
+    
+  // mark track segments which are crossing SM boundaries along chamber
+  if(TMath::Abs(alpha-param->GetAlpha())>.01) return kFALSE;
+  
+  return kTRUE;
 
+}