lcsim/sandbox/RobKutschke/TRFTests/v1

diff -N VTUtil.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ VTUtil.java	18 Sep 2007 17:54:53 -0000	1.1
@@ -0,0 +1,81 @@

+import org.lcsim.recon.tracking.trfbase.VTrack;
+import org.lcsim.recon.tracking.trfbase.Surface;
+
+import org.lcsim.recon.tracking.trfcyl.SurfCylinder;
+import org.lcsim.recon.tracking.trfzp.SurfZPlane;
+import hep.physics.vec.Hep3Vector;
+import hep.physics.vec.BasicHep3Vector;
+
+/**
+ * 
+ * Compute various derived quantities from a VTrack.
+ * Still under construction.
+ *
+ *@author $Author: kutschke $
+ *@version $Id: VTUtil.java,v 1.1 2007/09/18 17:54:53 kutschke Exp $
+ *
+ * Date $Date: 2007/09/18 17:54:53 $
+ *
+ */
+
+
+public class VTUtil {
+
+    public VTUtil( VTrack v){
+	this.v    = v;
+	Surface s = v.surface();
+
+	if ( s.pureType().equals( SurfCylinder.staticType()) ){
+	    DoCylinder();
+	} else{
+	    DoNull();
+	}
+    }
+
+    public double momentum(){ 
+	return p;
+    }
+
+    public Hep3Vector asHep3Vector(){
+	double px = pt*Math.cos(phi);
+	double py = pt*Math.sin(phi);
+	double pz = p *costh;
+	return new BasicHep3Vector(px,py,pz);
+    }
+
+    public double costh(){
+	return costh;
+    }
+
+    public double sinth(){
+	return sinth;
+    }
+
+    private VTrack v = null;
+    private double costh;
+    private double sinth;
+    private double cotth;
+    private double pt;
+    private double p;
+    private double phi;
+    private double phi0;
+
+    private void DoCylinder(){
+	    cotth = v.vector(SurfCylinder.ITLM);
+	    sinth = 1./Math.sqrt( 1. + cotth*cotth );
+	    costh = cotth*sinth;
+	    pt    = 1./Math.abs(v.vector(SurfCylinder.IQPT));
+	    p     = pt/sinth;
+	    phi   = v.vector(SurfCylinder.IPHI)+v.vector(SurfCylinder.IALF);
+    }
+    private void DoNull(){
+	cotth = 0.;
+	costh = 0.;
+	sinth = 0.;
+	pt    = 0.;
+	p     = 0.;
+	phi   = 0.;
+    }
+
+
+}