Fix N_hits issue & fill AHDC::track bank before KF

reconstruction/alert/src/main/java/org/jlab/rec/ahdc/HelixFit/HelixFitJava.java

@@ -997,7 +997,81 @@ public HelixFitObject HelixFit(int PointNum, double szPos[][], int fit_track_to_
 	    return h;
 	  }
 
-// Public weighted wrapper (similar to the original HelixFit)
+	// Compute the path length along the helix described by h,
+	// for the portion where the radial distance to the beamline
+	// (sqrt(x^2 + y^2)) is between rMin and rMax [mm].
+	private double computePathFromHelix(HelixFitObject h, double rMin, double rMax) {
+
+		// Helix parameters from the fit
+		double A   = h.get_A();   // circle center X in XY-plane
+		double B   = h.get_B();   // circle center Y in XY-plane
+		double X0  = h.get_X0();  // point of closest approach in XY
+		double Y0  = h.get_Y0();
+		double thDeg = h.get_Theta(); // already stored in degrees in the wrapper
+		double theta = Math.toRadians(thDeg); // convert to radians for sin()
+
+		// Circle radius in XY-plane
+		double R = Math.sqrt((X0 - A)*(X0 - A) + (Y0 - B)*(Y0 - B));
+		if (R < 1e-6) {
+			// Degenerate circle
+			return 0.0;
+		}
+
+		// Distance from origin to circle center
+		double C = Math.sqrt(A*A + B*B);
+
+		// Minimal / maximal distance from the circle to the origin
+		double Dmin = Math.abs(C - R);
+		double Dmax = C + R;
+
+		// If there is no overlap between [rMin, rMax] and [Dmin, Dmax], path = 0
+		if (rMax <= Dmin || rMin >= Dmax) {
+			return 0.0;
+		}
+
+		// Clip the requested radial window to what the circle actually covers
+		double rIn  = Math.max(rMin, Dmin);
+		double rOut = Math.min(rMax, Dmax);
+		if (rOut <= rIn) {
+			return 0.0;
+		}
+
+		// Helper constants for r^2(psi) = C0 + 2 R C cos(psi)
+		double C0 = A*A + B*B + R*R;
+
+		// Helper to compute psi(r) in [0,π] from r:
+		// cos(psi) = (r^2 - C0)/(2 R C)
+		java.util.function.DoubleFunction<Double> psiOfR = (double r) -> {
+			double num = r*r - C0;
+			double den = 2.0 * R * C;
+			if (Math.abs(den) < 1e-12) {
+				return 0.0;
+			}
+			double u = num / den;
+			// Clamp to [-1,1] to avoid NaN from acos
+			if (u >  1.0) u =  1.0;
+			if (u < -1.0) u = -1.0;
+			return Math.acos(u);  // in [0, π]
+		};
+
+		double psiIn  = psiOfR.apply(rIn);
+		double psiOut = psiOfR.apply(rOut);
+
+		double dPsi = Math.abs(psiOut - psiIn);
+
+		// ds/dpsi = R / sin(theta)
+		double sinTheta = Math.sin(theta);
+		if (Math.abs(sinTheta) < 1e-6) {
+			// Track almost parallel to the beam; this formula is ill-defined.
+			// Return 0 for safety or some large sentinel.
+			return 0.0;
+		}
+
+		double path = (R / sinTheta) * dPsi;
+
+		return path;
+	}
+    // Public weighted wrapper (similar to the original HelixFit)
 	  public HelixFitObject HelixFitWeighted(int PointNum, double[][] szPos,
 										double[] weights, int fit_track_to_beamline) {
 
@@ -1188,14 +1262,17 @@ public HelixFitObject helix_fit_with_doca_selection(List<DocaCluster> docaCluste
 		}
 
 		// weights = null => all weights = 1.0 inside helix_fit_weighted
+		// Use the DOCa-based bestChi2 as helix chi2
 
 	    double PI=Math.acos(0.0)*2;
 	    //double Rho=0,Phi=0,Theta=0,X0=0,Y0=0,DCA=0,Chi2=0;
             double Phi_deg;
             double Theta_deg;
 
-	    HelixFitObject h = helix_fit_weighted(nPoints, szPosSel, null, fit_track_to_beamline);;
-
+	    HelixFitObject h = helix_fit_weighted(nPoints, szPosSel, null, fit_track_to_beamline);
+	    h.set_Chi2(bestChi2);
+		double path = computePathFromHelix(h, 30.0, 70.0);
+		h.set_path(path);
 	    Phi_deg=Math.toDegrees(h.get_Phi());
             if(Phi_deg >= 180){
                 Phi_deg -= 360;
@@ -1211,6 +1288,4 @@ public HelixFitObject helix_fit_with_doca_selection(List<DocaCluster> docaCluste
 
 	}
 
-}
-
-
+}

reconstruction/alert/src/main/java/org/jlab/rec/ahdc/HelixFit/HelixFitObject.java

@@ -16,7 +16,8 @@ public class HelixFitObject {
     private double _DCA;
     private double _Chi2;
     private double _magfield;
-
+    private double _path;
+
     public HelixFitObject(){
         //default constructor
     }
@@ -33,6 +34,7 @@ public HelixFitObject(double Rho, double A, double B, double Phi, double Theta,
         _DCA = DCA;
         _Chi2 = Chi2;
         _magfield = 50;
+        _path = 0;
     }
     public double get_Rho(){
         return _Rho;
@@ -82,6 +84,9 @@ public double get_DCA(){
     public double get_Chi2(){
         return _Chi2;
     }
+    public void set_Chi2(double Chi2){
+        _Chi2 = Chi2;
+    }
     public double get_Mom(){
         return 0.3*_magfield*Math.abs(_Rho)/(10*Math.sin(Math.toRadians(_Theta)));
     }
@@ -103,5 +108,10 @@ public double get_dEdx(){
     public void set_magfield(double magfield){
         _magfield = magfield;
     }
-
+    public double get_path(){
+        return _path;
+    }
+    public void set_path(double path){
+        _path = path;
+    }    
 }

reconstruction/alert/src/main/java/org/jlab/rec/ahdc/Track/Track.java

@@ -73,6 +73,8 @@ public void setPositionAndMomentum(HelixFitObject helixFitObject) {
 		this.px0 = helixFitObject.get_px();
 		this.py0 = helixFitObject.get_py();
 		this.pz0 = helixFitObject.get_pz();
+		this.chi2 = helixFitObject.get_Chi2();
+		this.path = helixFitObject.get_path();
 	}
 
 	public void setPositionAndMomentumVec(double[] x) {
@@ -176,15 +178,40 @@ public void set_trackId(int _trackId) {
 	public void set_chi2(double _chi2) { chi2 = _chi2;}
 	public void set_sum_residuals(double _sum_residuals) { sum_residuals = _sum_residuals;}
 	public int    get_trackId() {return trackId;}
-	public int    get_n_hits() {return n_hits;}
-	public int    get_sum_adc() {return sum_adc;}
+	public int    get_n_hits() {
+    	if (hits == null) {
+    	    return 0;
+    	}
+    	return hits.size();
+	}
+	public int    get_sum_adc() {
+		if (hits == null || hits.isEmpty()) {
+			return 0;
+		}
+		int sum = 0;
+		for (Hit h : hits) {
+			sum += (int) Math.round(h.getADC());
+		}
+		return sum;
+	}
 	public double get_chi2() {return chi2;}
 	public double get_sum_residuals() {return sum_residuals;}
 	// AHDC::track
 	public void set_dEdx(double _dEdx) { dEdx = _dEdx;}
 	public void set_p_drift(double _p_drift) { p_drift = _p_drift;}
 	public void set_path(double _path) { path = _path;}
-	public double get_dEdx() {return dEdx;}
+	public double get_dEdx() {
+		if (path <= 0) {
+			dEdx = 0;
+		}else {
+			int sum = 0;
+			for (Hit h : hits) {
+				sum += (int) Math.round(h.getADC());
+			}
+			dEdx = sum/path; 
+		}
+		return dEdx;
+	}
 	public double get_p_drift() {return p_drift;}
 	public double get_path() {return path;}
 
@@ -196,4 +223,4 @@ public void set_trackId(int _trackId) {
     public int get_predicted_ATOF_layer() {return predicted_ATOF_layer;}
     public int get_predicted_ATOF_wedge() {return predicted_ATOF_wedge;}
 
-}
+}

reconstruction/alert/src/main/java/org/jlab/service/ahdc/AHDCEngine.java

@@ -218,13 +218,14 @@ else if (modeTrackFinding == ModeTrackFinding.CV_Hough) {
             // V) Global fit
             int trackid = 0;
             ArrayList<DocaCluster> all_docaClusters = new ArrayList<>();
+            AHDC_Tracks.removeIf(track -> track.get_Clusters().size() < 3);
             for (Track track : AHDC_Tracks) {
               trackid++;
               track.set_trackId(trackid);
               List<Cluster> originalClusters = track.get_Clusters();
               ArrayList<DocaCluster> docaClusters = DocaClusterRefiner.buildRefinedClusters(originalClusters);
               all_docaClusters.addAll(docaClusters);
-              if (docaClusters == null || docaClusters.size() < 3) {
+              if (docaClusters == null || docaClusters.size() < 3 || originalClusters == null || originalClusters.size() < 3) {
                 // not enough points, skip helix fit
                 continue;
               }
@@ -314,4 +315,4 @@ public static void main(String[] args) {
 
         System.out.println("finished " + (System.nanoTime() - starttime) * Math.pow(10, -9));
     }
-}
+}