DEHistogram.java

package umontreal.ssj.stat.density;
 
import umontreal.ssj.stat.ScaledHistogram;
import umontreal.ssj.stat.TallyHistogram;

 
public class DEHistogram extends DensityEstimator {

   private ScaledHistogram histDensity;

   public DEHistogram(double a, double b, int numBins) {
      histDensity = new ScaledHistogram(a, b, numBins);
   }

   public DEHistogram(double[] data, double a, double b, int numBins) {
      // this.data = data;
      TallyHistogram tallyHist = new TallyHistogram(a, b, numBins);
      tallyHist.fillFromArray(data);
      histDensity = new ScaledHistogram(tallyHist, tallyHist.getProportionInBoundaries());
   }

   public DEHistogram(TallyHistogram tallyHist) {
 
      histDensity = new ScaledHistogram(tallyHist, tallyHist.getProportionInBoundaries());
   }

   public DEHistogram(ScaledHistogram scaledHist) {
      histDensity = scaledHist;
   }

   @Override
   public void setData(double[] data) {
      TallyHistogram tallyHist = new TallyHistogram(histDensity.getA(), histDensity.getB(), histDensity.getNumBins());
      tallyHist.fillFromArray(data);
      histDensity = new ScaledHistogram(tallyHist, tallyHist.getProportionInBoundaries());
   }

   public ScaledHistogram getScaledHistogram() {
      return histDensity;
   }

   public int getNumBins() {
      return histDensity.getNumBins();
   }

   public double getH() {
      return (getB() - getA()) / getNumBins();
   }

   public double getA() {
      return histDensity.getA();
   }

   public double getB() {
      return histDensity.getB();
   }

   @Override
   public String toString() {
      return "Histogram estimator with " + getNumBins() + " bins.";
   }

   @Override
   public double evalDensity(double x) {
      return histDensity.getHeights()[(int) ((x - getA()) / getH())];
   }

   @Override
   public double[] evalDensity(double[] evalPoints) {
      int k = evalPoints.length;
      double[] density = new double[k];
 
      for (int j = 0; j < k; j++)
         density[j] = histDensity.getHeights()[(int) ((evalPoints[j] - getA()) / getH())];
 
      return density;
 
   }

   public double[] evalDensity() {
      return histDensity.getHeights();
   }

   public void setH(double h) {
      int numBins = (int) ((getB() - getA()) / h);
      TallyHistogram tallyHist = new TallyHistogram(histDensity.getA(), histDensity.getB(), numBins);
      tallyHist.fillFromArray(data);
      histDensity = new ScaledHistogram(tallyHist, tallyHist.getProportionInBoundaries());
 
   }
 
   // STATIC METHODS

   public static double evalDensity(double x, double[] data, double a, double b, int numBins) {
      TallyHistogram tallyHist = new TallyHistogram(a, b, numBins);
      tallyHist.fillFromArray(data);
      return evalDensity(x, tallyHist);
   }

   public static double[] evalDensity(double[] evalPoints, double[] data, double a, double b, int numBins) {
      TallyHistogram tallyHist = new TallyHistogram(a, b, numBins);
      tallyHist.fillFromArray(data);
      return evalDensity(evalPoints, tallyHist);
   }

 
   public static double[] evalDensity(double[] data, double a, double b, int numBins) {
      TallyHistogram tallyHist = new TallyHistogram(a, b, numBins);
      tallyHist.fillFromArray(data);
      return evalDensity(tallyHist);
   }

   public static double[][] evalDensity(double[][] data, double a, double b, int numBins) {
      int m = data.length;
      double[][] dens = new double[m][numBins];
      TallyHistogram tallyHist = new TallyHistogram(a, b, numBins);
      for (int r = 0; r < m; r++) {
         tallyHist.fillFromArray(data[r]);
         dens[r] = evalDensity(tallyHist);
      }
      return dens;
   }

   public static double[][] evalDensity(double evalPoints[], double[][] data, double a, double b, int numBins) {
      int m = data.length;
      double[][] dens = new double[m][numBins];
      TallyHistogram tallyHist = new TallyHistogram(a, b, numBins);
      for (int r = 0; r < m; r++) {
         tallyHist.fillFromArray(data[r]);
         dens[r] = evalDensity(evalPoints, tallyHist);
      }
      return dens;
   }

   public static double evalDensity(double x, TallyHistogram tallyHist) {
      ScaledHistogram hist = new ScaledHistogram(tallyHist, tallyHist.getProportionInBoundaries());
      double h = (hist.getB() - hist.getA()) / (double) hist.getNumBins();
      return hist.getHeights()[(int) ((x - hist.getA()) / h)];
   }

   public static double[] evalDensity(double[] evalPoints, TallyHistogram tallyHist) {
 
      ScaledHistogram hist = new ScaledHistogram(tallyHist, tallyHist.getProportionInBoundaries());
      int k = evalPoints.length;
      double[] density = new double[k];
      double h = (hist.getB() - hist.getA()) / (double) hist.getNumBins();
      for (int j = 0; j < k; j++) {
         density[j] = hist.getHeights()[(int) ((evalPoints[j] - hist.getA()) / h)];
      }
      return density;
   }

   public static double[] evalDensity(TallyHistogram tallyHist) {
      ScaledHistogram hist = new ScaledHistogram(tallyHist, tallyHist.getProportionInBoundaries());
      return hist.getHeights();
   }

   public static double[][] evalDensity(double[] evalPoints, TallyHistogram[] tallyHistArray) {
      int m = tallyHistArray.length;
      int k = evalPoints.length;
      double[][] density = new double[m][k];
      for (int r = 0; r < m; r++)
         density[r] = evalDensity(evalPoints, tallyHistArray[r]);
      return density;
   }

   public static double[][] evalDensity(TallyHistogram[] tallyHistArray) {
      int m = tallyHistArray.length;
      double[][] dens = new double[m][];
      for (int r = 0; r < m; r++)
         dens[r] = evalDensity(tallyHistArray[r]);
      return dens;
   }

 
   public static double evalDensity(double x, ScaledHistogram scaledHist) {
      double h = (scaledHist.getB() - scaledHist.getA()) / (double) scaledHist.getNumBins();
      return scaledHist.getHeights()[(int) ((x - scaledHist.getA()) / h)];
   }

   public static double[] evalDensity(double[] evalPoints, ScaledHistogram scaledHist) {
      int k = evalPoints.length;
      double[] density = new double[k];
      double h = (scaledHist.getB() - scaledHist.getA()) / (double) scaledHist.getNumBins();
      for (int j = 0; j < k; j++)
         density[k] = scaledHist.getHeights()[(int) ((evalPoints[j] - scaledHist.getA()) / h)];
      return density;
   }

   public static double[] evalDensity(ScaledHistogram scaledHist) {
      return scaledHist.getHeights();
   }

   public static double[][] evalDensity(double[] evalPoints, ScaledHistogram[] scaledHistArray) {
      int m = scaledHistArray.length;
      double[][] density = new double[m][];
 
      for (int r = 0; r < m; r++)
         density[m] = evalDensity(evalPoints, scaledHistArray[r]);
 
      return density;
   }

   public static double[][] evalDensity(ScaledHistogram[] scaledHistArray) {
      int m = scaledHistArray.length;
      double[][] density = new double[m][];
      for (int r = 0; r < m; r++)
         density[r] = evalDensity(scaledHistArray[r]);
 
      return density;
   }
 
}