Put only first generation decay products on the stack.

diff --git a/EVGEN/AliGenParam.cxx b/EVGEN/AliGenParam.cxx
index 3ca54db3b3161e94687a0ee813a95585d6415d1c..80dc91c5e01f5abe0fcc17c81c4aa63538dfda47 100644 (file)
--- a/EVGEN/AliGenParam.cxx
+++ b/EVGEN/AliGenParam.cxx
@@ -15,6 +15,9 @@
 
 /*
 $Log$
+Revision 1.29  2001/03/27 10:58:41  morsch
+Initialize decayer before generation. Important if run inside cocktail.
+
 Revision 1.28  2001/03/09 13:01:41  morsch
 - enum constants for paramterisation type (particle family) moved to AliGen*lib.h
 - use AliGenGSIlib::kUpsilon, AliGenPHOSlib::kEtaPrime to access the constants
@@ -409,49 +412,56 @@ void AliGenParam::Generate()
 // select decay particles
              Int_t np=fDecayer->ImportParticles(particles);
              Int_t ncsel=0;
-             for (i = 1; i<np; i++) {
-                 TParticle *  iparticle = (TParticle *) particles->At(i);
-                 Int_t kf = iparticle->GetPdgCode();
+
+             if (np >1) {
+                 TParticle* iparticle =  (TParticle *) particles->At(0);
+                 Int_t ipF = iparticle->GetFirstDaughter();
+                 Int_t ipL = iparticle->GetLastDaughter();           
+                 for (i = ipF-1; i<ipL; i++) {
+                     iparticle = (TParticle *) particles->At(i);
+                     Int_t kf = iparticle->GetPdgCode();
 //
 // children
-                 if (ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll)
-                 {
-                     pc[0]=iparticle->Px();
-                     pc[1]=iparticle->Py();
-                     pc[2]=iparticle->Pz();
-                     och[0]=origin0[0]+iparticle->Vx()/10;
-                     och[1]=origin0[1]+iparticle->Vy()/10;
-                     och[2]=origin0[2]+iparticle->Vz()/10;
-                     if (fCutOnChild) {
-                         Float_t ptChild=TMath::Sqrt(pc[0]*pc[0]+pc[1]*pc[1]);
-                         Float_t pChild=TMath::Sqrt(ptChild*ptChild+pc[2]*pc[2]);
-                         Float_t thetaChild=TMath::ATan2(ptChild,pc[2]);
-                         Float_t phiChild=TMath::ATan2(pc[1],pc[0]);
-                         Bool_t childok = 
-                             ((ptChild    > fChildPtMin    && ptChild    <fChildPtMax)      &&
-                              (pChild     > fChildPMin     && pChild     <fChildPMax)       &&
-                              (thetaChild > fChildThetaMin && thetaChild <fChildThetaMax)   &&
-                              (phiChild   > fChildPhiMin   && phiChild   <fChildPhiMax));
-                         if(childok)
-                         {
+                     if (ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll)
+                     {
+                         pc[0]=iparticle->Px();
+                         pc[1]=iparticle->Py();
+                         pc[2]=iparticle->Pz();
+                         och[0]=origin0[0]+iparticle->Vx()/10;
+                         och[1]=origin0[1]+iparticle->Vy()/10;
+                         och[2]=origin0[2]+iparticle->Vz()/10;
+                         if (fCutOnChild) {
+                             Float_t ptChild=TMath::Sqrt(pc[0]*pc[0]+pc[1]*pc[1]);
+                             Float_t pChild=TMath::Sqrt(ptChild*ptChild+pc[2]*pc[2]);
+                             Float_t thetaChild=TMath::ATan2(ptChild,pc[2]);
+                             Float_t phiChild=TMath::ATan2(pc[1],pc[0]);
+                             Bool_t childok = 
+                                 ((ptChild    > fChildPtMin    && ptChild    <fChildPtMax)      &&
+                                  (pChild     > fChildPMin     && pChild     <fChildPMax)       &&
+                                  (thetaChild > fChildThetaMin && thetaChild <fChildThetaMax)   &&
+                                  (phiChild   > fChildPhiMin   && phiChild   <fChildPhiMax));
+                             if(childok)
+                             {
+                                 pch[ncsel][0]=pc[0];
+                                 pch[ncsel][1]=pc[1];
+                                 pch[ncsel][2]=pc[2];
+                                 kfch[ncsel]=kf;
+                                 ncsel++;
+                             } else {
+                                 ncsel=-1;
+                                 break;
+                             } // child kine cuts
+                         } else {
                              pch[ncsel][0]=pc[0];
                              pch[ncsel][1]=pc[1];
                              pch[ncsel][2]=pc[2];
                              kfch[ncsel]=kf;
                              ncsel++;
-                         } else {
-                             ncsel=-1;
-                             break;
-                         } // child kine cuts
-                     } else {
-                         pch[ncsel][0]=pc[0];
-                         pch[ncsel][1]=pc[1];
-                         pch[ncsel][2]=pc[2];
-                         kfch[ncsel]=kf;
-                         ncsel++;
-                     } // if child selection
-                 } // select muon
-             } // decay particle loop
+                         } // if child selection
+                     } // select muon
+                 } // decay particle loop
+             } // if decay products
+             
              Int_t iparent;
              if ((fCutOnChild && ncsel >0) || !fCutOnChild){
                  ipa++;