Playing around with added residuals to tree

src/THcDC.cxx

@@ -333,6 +333,7 @@ Int_t THcDC::DefineVariables( EMode mode )
     { "y", "Y at focal plane", "fDCTracks.THcDCTrack.GetY()"},
     { "xp", "YP at focal plane", "fDCTracks.THcDCTrack.GetXP()"},
     { "yp", "YP at focal plane", "fDCTracks.THcDCTrack.GetYP()"},
+    { "p1residual", "Plane 1 Residual", "fDCTracks.THcDCTrack.GetResidual1()"},
     { 0 }
   };
   return DefineVarsFromList( vars, mode );

src/THcDCTrack.h

@@ -34,6 +34,7 @@ public:
   Int_t GetNFree()                const {return fNfree;}
   Double_t GetCoord(Int_t ip)     const {return fCoords[ip];}
   Double_t GetResidual(Int_t ip)     const {return fResiduals[ip];}
+  Double_t GetResidual1()     const {return fResiduals[0];}
   void GetRay(Double_t *ray) const {ray[0]=fX_fp; ray[1]=fY_fp; ray[2]=fXp_fp; ray[3]=fYp_fp;}
   Double_t GetX()                 const {return fX_fp;}
   Double_t GetY()                 const {return fY_fp;}