Introducing hyperons in ESD (Yu.Belikov)

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

diff --git a/STEER/AliESDtrack.cxx b/STEER/AliESDtrack.cxx
index 3e6f9bc0c1c2b52d202ec531f67ec9a76bc304e3..cbd6aa486ca864bf4e5ddf554934ad80b4b0e584 100644 (file)
--- a/STEER/AliESDtrack.cxx
+++ b/STEER/AliESDtrack.cxx
@@ -102,6 +102,24 @@ Bool_t AliESDtrack::UpdateTrackParams(const AliKalmanTrack *t, ULong_t flags) {
   return kTRUE;
 }
 
+//_______________________________________________________________________
+void AliESDtrack::GetExternalParametersAt(Double_t x, Double_t p[5]) const {
+  //---------------------------------------------------------------------
+  // This function returns external representation of the track parameters
+  // at the plane x
+  //---------------------------------------------------------------------
+  Double_t dx=x-fRx;
+  Double_t c=fRp[4]/AliKalmanTrack::GetConvConst();
+  Double_t f1=fRp[2], f2=f1 + c*dx;
+  Double_t r1=sqrt(1.- f1*f1), r2=sqrt(1.- f2*f2);    
+
+  p[0]=fRp[0]+dx*(f1+f2)/(r1+r2);
+  p[1]=fRp[1]+dx*(f1+f2)/(f1*r2 + f2*r1)*fRp[3];
+  p[2]=fRp[2]+dx*c;
+  p[3]=fRp[3];
+  p[4]=fRp[4];
+}
+
 //_______________________________________________________________________
 void AliESDtrack::GetExternalParameters(Double_t &x, Double_t p[5]) const {
   //---------------------------------------------------------------------