silvermy@ornl.gov - SMcalib - directory with tools for SuperModule calibrations at...

[u/mrichter/AliRoot.git] / STEER / AliTrackFitter.cxx

diff --git a/STEER/AliTrackFitter.cxx b/STEER/AliTrackFitter.cxx
index dfce869f045aa3c85345ba60765894d43ca41bae..a02d87747b9005ac7c6bea494279b708bbeba4cc 100644 (file)
--- a/STEER/AliTrackFitter.cxx
+++ b/STEER/AliTrackFitter.cxx
@@ -163,3 +163,120 @@ Bool_t AliTrackFitter::FindVolId(const TArrayI *array, UShort_t volid) const
 
   return found;
 }
+
+Bool_t AliTrackFitter::Fit(const TArrayI *volIds,const TArrayI *volIdsFit,
+AliGeomManager::ELayerID layerRangeMin,
+AliGeomManager::ELayerID layerRangeMax)
+{
+  //-------------------------------------------------------------------
+  //
+  //                      Fit the track points. 
+  //
+  // volIds    - the array of IDs of volumes where the residuals 
+  //             will be calculated.
+  // volIdsFit - the array of IDs of volumes having the points
+  //              that will be fitted
+  // 
+  // If volIdsFit==0, the IDs of volumes having the points to fit
+  // are taken in the range defined by the two last parameters
+  // 
+  //
+  // The function fills two track-point arrays: fPVolId and fPTrack.
+  // The first one contains the track points from the volumes with IDs  
+  // taken from the "volIds". The second array is filled with 
+  // the intersection points between the fitted track and the volumes
+  // the points from the first arry belong to.
+  //
+  // The two arrays are used for calculation of the residuals
+  // and for the construction of a chi2 function to be minimized 
+  // in the alignment procedures. 
+  //
+  //--------------------------------------------------------------------
+
+  Int_t npoints=fPoints->GetNPoints();
+  if (npoints<fMinNPoints) return kFALSE;
+
+  // Fast counting the points
+  Int_t countFit=0;
+  Int_t countPnt=0;
+
+  Int_t fst=-1;
+  Int_t lst=-1;
+  if (volIdsFit != 0x0) {
+     for (Int_t i=0; i<npoints; i++) {
+         if (FindVolId(volIds,   fPoints->GetVolumeID()[i])) countPnt++;
+         if (FindVolId(volIdsFit,fPoints->GetVolumeID()[i])) {
+            countFit++;
+            if (fst<0) fst=i;
+            lst=i;
+         }
+     }
+  } else {
+     for (Int_t i=0; i<npoints; i++) {
+         UShort_t id=fPoints->GetVolumeID()[i]; 
+         if (FindVolId(volIds,id)) countPnt++;
+         if (id < AliGeomManager::LayerToVolUID(layerRangeMin,0)) continue;
+        if (id > AliGeomManager::LayerToVolUID(layerRangeMax,
+                 AliGeomManager::LayerSize(layerRangeMax))) continue;
+         countFit++;
+         if (fst<0) fst=i;
+         lst=i;
+     }
+  }
+  if (countPnt==0) return kFALSE;
+  if (countFit<fMinNPoints) return kFALSE;
+
+
+
+  //************* Fit the selected track points
+
+  if (!Begin(fst,lst)) return kFALSE;
+
+  AliTrackPoint p;
+  if (volIdsFit != 0x0) {
+     for (Int_t i=0; i<npoints; i++) {
+         if (!FindVolId(volIdsFit,fPoints->GetVolumeID()[i])) continue;
+         fPoints->GetPoint(p,i);
+         if (!AddPoint(&p)) return kFALSE;
+     }
+  } else {
+     for (Int_t i=0; i<npoints; i++) {
+         UShort_t id=fPoints->GetVolumeID()[i]; 
+         if (id < AliGeomManager::LayerToVolUID(layerRangeMin,0)) continue;
+        if (id > AliGeomManager::LayerToVolUID(layerRangeMax,
+                 AliGeomManager::LayerSize(layerRangeMax))) continue;
+         fPoints->GetPoint(p,i);
+         if (!AddPoint(&p)) continue;
+     }
+  }
+
+  if (!Update()) return kFALSE;
+
+
+
+
+  //************* Calculate the intersection points
+
+  fPVolId = new AliTrackPointArray(countPnt);
+  fPTrack = new AliTrackPointArray(countPnt);
+
+  Int_t n=0;
+  AliTrackPoint p2;
+  for (Int_t i=0; i<npoints; i++) {
+      if (!FindVolId(volIds,fPoints->GetVolumeID()[i])) continue;
+      fPoints->GetPoint(p,i);
+      if (GetPCA(p,p2)) {
+       fPVolId->AddPoint(n,&p);
+       fPTrack->AddPoint(n,&p2);
+        n++;
+      } else {
+       delete fPVolId;
+       fPVolId=0;
+       delete fPTrack;
+       fPTrack=0;
+       return kFALSE;
+      }
+  }
+  
+  return kTRUE;
+}