c-dilks · Oct 12, 2026
@@ -0,0 +1,23 @@
+package org.jlab.clas.tracking.utilities;
+
+import org.apache.commons.math3.special.Gamma;
+
+/** Chi-square probability utilities */
+public class ProbChi2perNDF {
+
+  /**
+   * Returns the upper-tail probability (survival function, or p-value) of the
+   * chi-square distribution: P(X &gt;= chi2) for X ~ &chi;&sup2;(ndf).
+   * @param chi2 the chi-square statistic
+   * @param ndf the number of degrees of freedom
+   * @return the probability of observing a chi-square value at least as large as {@code chi2}, in the range [0, 1]
+   */
+  public static double prob(double chi2, int ndf) {
+    if(ndf <= 0)
+      return 0.0;
+    if(chi2 <= 0.0) { // edge cases follow ROOT's `TMath::Prob` conventions
+      return chi2 < 0.0 ? 0.0 : 1.0;
+    }
+    return Gamma.regularizedGammaQ(0.5 * ndf, 0.5 * chi2);
+  }
+}
@@ -36,12 +36,6 @@
       <artifactId>j4ml-clas12</artifactId>
     </dependency>
 
-    <dependency>
-      <groupId>org.jlab.plugins</groupId>
-      <artifactId>trackfitter</artifactId>
-      <version>1.0</version>
-    </dependency>
-
     <dependency>
       <groupId>org.jlab.clas</groupId>
       <artifactId>clas-io</artifactId>

@@ -85,11 +85,6 @@
       <scope>test</scope>
       <type>jar</type>
     </dependency>
-    <dependency>
-      <groupId>org.jlab.plugins</groupId>
-      <artifactId>trackfitter</artifactId>
-      <version>1.0</version>
-    </dependency>
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>

@@ -269,7 +269,7 @@ public static double getRCUT() {
         return RCUT;
     }
 
-    public static void setRCUT(double r) {
+    private static void setRCUT(double r) {
         RCUT = r;
     }
 
@@ -281,7 +281,7 @@ public static double getZRANGE() {
         return ZRANGE;
     }
 
-    public static void setZRANGE(double zr) {
+    private static void setZRANGE(double zr) {
         ZRANGE = zr;
     }
 

@@ -6,7 +6,7 @@
 import org.jlab.geom.prim.Point3D;
 import org.jlab.geom.prim.Vector3D;
 import org.jlab.rec.cvt.trajectory.Ray;
-import trackfitter.fitter.utilities.ProbChi2perNDF;
+import org.jlab.clas.tracking.utilities.ProbChi2perNDF;
 
 /**
  * A fitter which does sequential fit (for x, y coordinates) and then (for r, z
@@ -21,7 +21,6 @@ public class CosmicFitter {
     private CosmicFitPars _rayfitoutput;
 
     private LineFitPars _linefitparsRhoZ;
-    private LineFitPars _linefitparsYX;
     /**
      * Status of the HelicalTrackFit
      */
@@ -164,7 +163,7 @@ public FitStatus fit2(List<Double> X, List<Double> Y, List<Double> Z, List<Doubl
 
         //Line fits
         _linefitYX = new LineFitter();
-        boolean linefitstatusXYOK = _linefitYX.fitStatus(Y, X, errRt, new ArrayList<>(X.size()), X.size());
+        _linefitYX.fitStatus(Y, X, errRt, new ArrayList<>(X.size()), X.size());
 
         _linefitRhoZ = new LineFitter();
         boolean linefitstatusOK = _linefitRhoZ.fitStatus(Rho, Z, errRho, ErrZ, Z.size());
@@ -174,7 +173,6 @@ public FitStatus fit2(List<Double> X, List<Double> Y, List<Double> Z, List<Doubl
         }
         //  Get the results of the fits
         _linefitparsRhoZ = _linefitRhoZ.getFit();
-        _linefitparsYX = _linefitYX.getFit();
 
         double fit_tandip = _linefitparsRhoZ.slope();
         double fit_Z0 = _linefitparsRhoZ.intercept();

@@ -1,7 +1,7 @@
 package org.jlab.rec.cvt.fit;
 
 import org.jlab.rec.cvt.trajectory.Ray;
-import trackfitter.fitter.utilities.ProbChi2perNDF;
+import org.jlab.clas.tracking.utilities.ProbChi2perNDF;
 
 /**
  * The fit parameters of a line fit returned by LineFitter

@@ -3,7 +3,6 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -24,7 +23,7 @@
 import org.jlab.rec.cvt.trajectory.Helix;
 import org.jlab.rec.cvt.trajectory.StateVec;
 import org.jlab.rec.cvt.trajectory.Trajectory;
-import trackfitter.fitter.utilities.ProbChi2perNDF;
+import org.jlab.clas.tracking.utilities.ProbChi2perNDF;
 
 /**
  * A class representing track candidates in the CVT. A track has a trajectory
@@ -328,9 +327,9 @@ else if(this.getChi2() > Constants.CHI2CUT * (this.getNDF() + 5))
             return false;
         if(this.getNDF() < Constants.NDFCUT) 
             return false;
-        if(this.getHelix().radius() < Constants.getInstance().getRCUT()) 
+        if(this.getHelix().radius() < Constants.getRCUT()) 
             return false;
-        if(Math.abs(Geometry.getInstance().getTargetZOffset()-this.getHelix().getZ0()) > Geometry.getInstance().getTargetHalfLength()+Constants.getInstance().getZRANGE()) 
+        if(Math.abs(Geometry.getInstance().getTargetZOffset()-this.getHelix().getZ0()) > Geometry.getInstance().getTargetHalfLength()+Constants.getZRANGE()) 
             return false;
         else 
             return true;

@@ -97,11 +97,6 @@
       <artifactId>snr</artifactId>
       <version>14.2.1-SNAPSHOT</version>
     </dependency>
-    <dependency>
-      <groupId>org.jlab.plugins</groupId>
-      <artifactId>trackfitter</artifactId>
-      <version>1.0</version>
-    </dependency>
     <dependency>
       <groupId>org.jlab.clas</groupId>
       <artifactId>swim-tools</artifactId>

@@ -13,7 +13,7 @@
 import org.jlab.rec.dc.segment.Segment;
 import org.jlab.rec.dc.track.Track;
 
-import trackfitter.fitter.utilities.*;
+import org.jlab.clas.tracking.utilities.ProbChi2perNDF;
 
 /**
  * A class to fill the reconstructed DC banks
@@ -36,8 +36,8 @@ public RecoBankWriter(Banks names) {
 
     public void updateListsWithClusterInfo(List<FittedHit> fhits,
             List<FittedCluster> clusters) {
-        ArrayList rmHits = new ArrayList<FittedHit>();
-        ArrayList addHits = new ArrayList<FittedHit>();
+        List<FittedHit> rmHits = new ArrayList<>();
+        List<FittedHit> addHits = new ArrayList<>();
         for (int i = 0; i < clusters.size(); i++) {
             clusters.get(i).set_Id(i + 1);
             for (int j = 0; j < clusters.get(i).size(); j++) {
@@ -204,8 +204,6 @@ public DataBank fillHBClustersBank(DataEvent event, List<FittedCluster> cluslist
     DataBank bank = event.createBank(name, cluslist.size());
 
     int[] hitIdxArray = new int[12];
-    if(cluslist==null)
-        return bank;
     for (int i = 0; i < cluslist.size(); i++) {
         if (cluslist.get(i) == null || cluslist.get(i).get_Id() == -1) {
             continue;

@@ -15,7 +15,7 @@
 import org.jlab.rec.dc.segment.Segment;
 import org.jlab.rec.dc.timetodistance.TimeToDistanceEstimator;
 import org.jlab.utils.groups.IndexedTable;
-import trackfitter.fitter.LineFitter;
+import org.jlab.rec.dc.track.fit.basefit.LineFitter;
 
 /**
  * A class with methods used to find lists of crosses.  This is the Pattern Recognition step used in track seeding, to