From: gconesab <gconesab@f7af4fe6-9843-0410-8265-dc069ae4e863>
Date: Thu, 20 Sep 2012 15:03:56 +0000 (+0000)
Subject:  protections agains 0 energy - Salvatore
X-Git-Url: http://git.uio.no/git/?a=commitdiff_plain;h=a840d58957c483beae4f7ab9e53f4610422cb435;p=u%2Fmrichter%2FAliRoot.git

 protections agains 0 energy - Salvatore
---

diff --git a/EMCAL/AliEMCALRecoUtils.cxx b/EMCAL/AliEMCALRecoUtils.cxx
index c2ac8c1bc07..5ef377283fc 100644
--- a/EMCAL/AliEMCALRecoUtils.cxx
+++ b/EMCAL/AliEMCALRecoUtils.cxx
@@ -841,15 +841,22 @@ Float_t  AliEMCALRecoUtils::GetDepth(const Float_t energy,
   Float_t x0    = 1.31;
   Float_t ecr   = 8;
   Float_t depth = 0;
+  Float_t arg   = energy*1000/ ecr; //Multiply energy by 1000 to transform to MeV
   
   switch ( iParticle )
   {
     case kPhoton:
-      depth = x0 * (TMath::Log(energy*1000/ ecr) + 0.5); //Multiply energy by 1000 to transform to MeV
+      if (arg < 1) 
+	depth = 0;
+      else
+	depth = x0 * (TMath::Log(arg) + 0.5); 
       break;
       
     case kElectron:
-      depth = x0 * (TMath::Log(energy*1000/ ecr) - 0.5); //Multiply energy by 1000 to transform to MeV
+      if (arg < 1) 
+	depth = 0;
+      else
+	depth = x0 * (TMath::Log(arg) - 0.5); 
       break;
       
     case kHadron:
@@ -872,13 +879,19 @@ Float_t  AliEMCALRecoUtils::GetDepth(const Float_t energy,
       }
       else
       {//electron
-        depth = x0 * (TMath::Log(energy*1000 / ecr)  - 0.5); //Multiply energy by 1000 to transform to MeV
+	if (arg < 1) 
+	  depth = 0;
+	else
+	  depth = x0 * (TMath::Log(arg) - 0.5); 
       }
         
       break;
       
     default://photon
-      depth = x0 * (TMath::Log(energy*1000 / ecr) + 0.5); //Multiply energy by 1000 to transform to MeV
+      if (arg < 1) 
+	depth = 0;
+      else
+	depth = x0 * (TMath::Log(arg) + 0.5);
   }  
   
   return depth;
@@ -1287,6 +1300,8 @@ void AliEMCALRecoUtils::RecalculateClusterPositionFromTowerGlobal(const AliEMCAL
   Bool_t shared = kFALSE;
 
   Float_t  clEnergy = clu->E(); //Energy already recalibrated previously
+  if (clEnergy <= 0)
+    return;
   GetMaxEnergyCell(geom, cells, clu, absId,  iSupModMax, ieta, iphi,shared);
   Double_t depth = GetDepth(clEnergy,fParticleType,iSupModMax) ;
   
@@ -1370,6 +1385,8 @@ void AliEMCALRecoUtils::RecalculateClusterPositionFromTowerIndex(const AliEMCALG
   Bool_t shared = kFALSE;
 
   Float_t clEnergy = clu->E(); //Energy already recalibrated previously.
+  if (clEnergy <= 0)
+    return;
   GetMaxEnergyCell(geom, cells, clu, absId,  iSupModMax, ieta, iphi,shared);
   Float_t  depth = GetDepth(clEnergy,fParticleType,iSupMod) ;
 
diff --git a/EMCAL/AliEMCALRecoUtils.h b/EMCAL/AliEMCALRecoUtils.h
index c3c7e492fac..d2236466ec6 100644
--- a/EMCAL/AliEMCALRecoUtils.h
+++ b/EMCAL/AliEMCALRecoUtils.h
@@ -63,7 +63,8 @@ public:
   void     RecalculateClusterPositionFromTowerIndex (const AliEMCALGeometry *geom, AliVCaloCells* cells, AliVCluster* clu); 
   void     RecalculateClusterPositionFromTowerGlobal(const AliEMCALGeometry *geom, AliVCaloCells* cells, AliVCluster* clu); 
   
-  Float_t  GetCellWeight(const Float_t eCell, const Float_t eCluster) const { return TMath::Max( 0., fW0 + TMath::Log( eCell / eCluster )) ; }
+  Float_t  GetCellWeight(const Float_t eCell, const Float_t eCluster) const { if (eCell > 0 && eCluster > 0) return TMath::Max( 0., fW0 + TMath::Log( eCell / eCluster )) ;
+                                                                              else                           return 0.                                                    ; }
   
   Float_t  GetDepth(const Float_t eCluster, const Int_t iParticle, const Int_t iSM) const ;