Changes in external/TrackCovariance/SolTrack.cc [ebf40fd:00b14d5] in git

File:

• external/TrackCovariance/SolTrack.cc (modified) (1 diff)

external/TrackCovariance/SolTrack.cc

@@ -232 +232 @@
         //
         return kmh;
+}
+//
+Int_t SolTrack::FirstHit(Double_t &Xfirst, Double_t &Yfirst, Double_t &Zfirst)
+{
+        Int_t iFirst = -1;      
+        Int_t iFirstLay = -1;   // Default return with no hits
+        Xfirst = 0.;
+        Yfirst = 0.;
+        Zfirst = 0.;
+        Int_t Nmh = nmHit();    // # measurement hits
+        if(Nmh > 0){
+                Int_t    *ih = new Int_t   [Nmh];
+                Double_t *Xh = new Double_t[Nmh];
+                Double_t *Yh = new Double_t[Nmh];
+                Double_t *Zh = new Double_t[Nmh];
+                Double_t *dh = new Double_t[Nmh];
+                //
+                Int_t n = HitListXYZ(ih, Xh, Yh, Zh);   
+                //
+                for(Int_t i=0; i<Nmh; i++){
+                        Double_t rr = TMath::Sqrt(Xh[i]*Xh[i]+Yh[i]*Yh[i]);     // Hit radius           
+                        dh[i] = TMath::ASin(C() * TMath::Sqrt((rr * rr - D() * D()) / (1. + 2 * C() * D()))) / C();     // Arc length traveled
+                }
+                //
+                Int_t *hord = new Int_t[Nmh];                   // hit order by increasing arc length
+                TMath::Sort(Nmh, dh, hord, kFALSE);             // Order by increasing arc length
+                iFirst = hord[0];                               // First hit pointer
+                Xfirst = Xh[iFirst];
+                Yfirst = Yh[iFirst];
+                Zfirst = Zh[iFirst];
+                iFirstLay = ih[iFirst];
+                //
+                // Clean
+                delete [] ih;
+                delete [] Xh;
+                delete [] Yh;
+                delete [] Zh;
+                delete [] dh;
+                delete [] hord;
+        }
+//
+        return  iFirstLay;      // Return first hit layer number
 }
 //