////********************************************************************
// Histogram.java 
//
//********************************************************************
//   A simple histogram class. The setData(float f) finds in which bin
// the value falls for nBins between the given minimum and maximum
// values. An integer array keeps track of the number of times the input
// value fell into a particular bin.
//    The DataChart class is used to display the histogram. This class
// in turn uses the BarChart tool which needs the data passed as a 
// string array. This is not optimal but OK for demonstration purposes.
//
//********************************************************************

import java.awt.*;	
import java.applet.Applet;

//********************************************************************
public class Histogram {

  int [] bins = null;
  int nBins;
  float xLow,xHigh;
  float delBin;
 
  int overFlows=0,underFlows=0;

  DataChart  chart;
  String dataString=null;


  //----------------------------------------------------------------
  Histogram (int nBins, float xLow, float xHigh,int _width,int _height){
  
   this.nBins = nBins;
   this.xLow  = xLow;
   this.xHigh = xHigh;

   bins = new int[nBins];
   delBin = (xHigh-xLow)/(float)nBins;

   reset();
   chart = new DataChart(dataString, _width, _height);

  }

  //----------------------------------------------------------------
  // Extra constructor to allow for double values
  Histogram (int nBins, double xLow, double xHigh,int _width,int _height){
    this(nBins, (float) xLow, (float) xHigh, _width, _height);
  }

  //----------------------------------------------------------------
  void setData(double data){
    setData((float)data);
  }
  //----------------------------------------------------------------
  void setData(float data){
   
   if( data < xLow)
     underFlows++;
   else if ( data >= xHigh) 
     overFlows++;
   else{
     int bin = (int)((data-xLow)/delBin);
     if(bin >=0 && bin < nBins) bins[bin]++;
   }
  }    

  //----------------------------------------------------------------
  // To display the histogram in a chart, we need to pass the data
  // as a string. 
  public void graphIt(){
    dataString = "";
    for (int i=0; i<nBins; i++){
      dataString += bins[i] + " ";
    }
    chart.setData(dataString);
    chart.graphIt();
  }
  

  //----------------------------------------------------------------
  public void reset(){
    dataString = "";
    for (int i=0; i<nBins; i++){
      bins[i]=0;
      dataString = dataString + bins[i] + " ";
    }
  }
 	
}