getapplets.java

马氏距离判别(MahalanobisDistanceDiscrimination)的演示过程,求均值向量,协方差矩阵及线形判别函数

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.text.*;
 
public class GetApplets extends Applet implements ActionListener
{
	DecimalFormat form =new DecimalFormat ("0.00000");
	double[][] yanshi_g1    = new double[5][3];
	double[][] yanshi_g2    = new double[5][3];
	double[]   daipan       = new double[3];//样本数据
	double[]   yanshi_g1_x1 = new double[3];		
    double[]   yanshi_g2_x2 = new double[3];
	double[][] yanshi_x1_x  = new double[3][5]; 
	double[][] yanshi_tr_x1 = new double[5][3]; 
	double[][] yanshi_x2_x  = new double[3][5]; 
	double[][] yanshi_tr_x2 = new double[5][3];
	double[][] yanshi_g1_s1 = new double[3][3];
	double[][] yanshi_g2_s2 = new double[3][3];
	double[][] yanshi_g1_s  = new double[3][3]; //样本协差阵
	double[][] yanshi_a     = new double[3][1];     

    private TextArea textArea; //声明一个TextArea
public void init() 
{  
    initForm();
	
	yanshi_g1[0][0]=76;   yanshi_g1[0][1]=99;   yanshi_g1[0][2]=5374;
  	yanshi_g1[1][0]=79.5; yanshi_g1[1][1]=99;   yanshi_g1[1][2]=5359;
  	yanshi_g1[2][0]=78;   yanshi_g1[2][1]=99;   yanshi_g1[2][2]=5372;
  	yanshi_g1[3][0]=72.1; yanshi_g1[3][1]=95.9; yanshi_g1[3][2]=5242;
    yanshi_g1[4][0]=73.8; yanshi_g1[4][1]=77.7; yanshi_g1[4][2]=5370;
	yanshi_g2[0][0]=71.2; yanshi_g2[0][1]=93;   yanshi_g2[0][2]=4250;
  	yanshi_g2[1][0]=75.3; yanshi_g2[1][1]=94.9; yanshi_g2[1][2]=3412;
    yanshi_g2[2][0]=70;   yanshi_g2[2][1]=91.2; yanshi_g2[2][2]=3390;
  	yanshi_g2[3][0]=72.8; yanshi_g2[3][1]=99;   yanshi_g2[3][2]=2300;
  	yanshi_g2[4][0]=62.9; yanshi_g2[4][1]=80.6; yanshi_g2[4][2]=3799;
	daipan[0] = 68.5;     daipan[1]=79.3;       daipan[2]=1950;
Button b=new Button("演示");
b.addActionListener(this);
setLayout(new BorderLayout());

add("East",b);
textArea=new TextArea(5,40);
textArea.setEditable(false);
add("Center",textArea);
}

void initForm()
	{
setSize(500,500);}


/*Button b点击后的事件处理函数*/
public void actionPerformed(ActionEvent event)
{ this.textArea.append("均值向量1:\n");
   average(yanshi_g1,5,3); 
  this.textArea.append("\n均值向量2:\n");
	bverage(yanshi_g2,5,3);
  this.textArea.append("\n样本协方差阵:\n");
	xfch(yanshi_g1,5,3,yanshi_g2,5,3);
	this.textArea.append("\n判别函数:\n");
	panbie(yanshi_g1_s,3,3,yanshi_g1_x1,yanshi_g2_x2);
	
	
}
/*求均值向量*/
public double [] average(double [][] a,int nRows,int nCols)
    {
		for (int c = 0; c < nCols; ++c)	 {
			for(int r=0;r<nRows;++r) 
			{ double v = a[r][c];
			  yanshi_g1_x1[c] += v/nRows;
			}
          this.textArea.append(form.format(yanshi_g1_x1[c])+"\t");
         }
		return yanshi_g1_x1;
     }
public double [] bverage(double [][] b,int nRows,int nCols)
    {
		for (int c = 0; c < nCols; ++c)	 {
			for(int r=0;r<nRows;++r) 
			{ double v = b[r][c];
			  yanshi_g2_x2[c] += v/nRows;
			}
          this.textArea.append(form.format(yanshi_g2_x2[c])+"\t");
         }
		return yanshi_g2_x2;
     }
/*public double [][] transpose1(double [][] a,int nRows,int nCols)
{
	double[][] tv =new double[nCols][nRows];
	for(int r=0;r<nRows;++r){
		for (int c = 0; c < nCols; ++c){
			tv[c][r]=a[r][c];}
	}
	return tv;	
}
public double[][] add(double [][] a,double [][] b,int nRows,int nCols)
{
	double[][] sum = new double[nRows][nCols];
	   for (int r = 0; r < nRows; ++r) {
            for (int c = 0; c < nCols; ++c) {
                sum[r][c] = a[r][c] + b[r][c];
            }
        }

        return sum;
    }
 public double[][] multiply(double [][] a,double [][] b,int nRows,int nCols,int bCols)
    {
        double pv[][] = new double[nRows][bCols]; // product values

        // Compute values of the product.
        for (int r = 0; r < nRows; ++r) {
            for (int c = 0; c < bCols; ++c) {
                double dot = 0;
                for (int k = 0; k < nCols; ++k) {
                    dot += a[r][k] * b[k][c];
                }
                pv[r][c] = dot;
            }
        }

        return pv;
    }*/
//求样本协方差矩阵
public double[][] xfch(double [][] a,int aRows,int aCols,double[][]b,int bRows,int bCols)
 {   int c=0,r=0,i=0;
	 double ta[][]=new double[3][5];
	 double as[][]=new double[aRows][aCols];
     double tas[][]=new double[aCols][aCols];
	 double tb[][]=new double[3][5];
	 double bs[][]=new double[bRows][bCols];
     double tbs[][]=new double[bCols][bCols];
	//第一个样本协方差矩阵
	 for(c=0; c < aCols; ++c)
	 {
		 for( r=0;r<aRows;++r)
		 {
			  as[r][c] = a[r][c] -yanshi_g1_x1[c] ;
	//	this.textArea.append(as[r][c]+ "\t ");
		 
		 }
		//this.textArea.append("\n");
	 }
 // this.textArea.append("tran：");
   for(r=0;r<aRows;++r){
		for (c = 0; c < aCols; ++c){
			ta[c][r]=as[r][c];
		//	this.textArea.append(ta[c][r]+"\t");
		}
		//this.textArea.append("\n");
	}
 //  this.textArea.append("chengji:");
   for (  i = 0; i < aCols; ++i){
   for ( c = 0; c < aCols; ++c) {
	   tas[i][c] = 0;
         for ( r= 0; r< aRows; ++r) 
			tas[i][c] += ta[i][r]*as[r][c]  ;
	//	 this.textArea.append(tas[i][c]+" ");
				  }
 //  this.textArea.append("\n");
  	}
       
//第二个样本协方差矩阵
	  for(c=0; c < bCols; ++c)
	 {
		 for( r=0;r<bRows;++r)
		 {
			  bs[r][c] = b[r][c] -yanshi_g2_x2[c] ;
	//	this.textArea.append(bs[r][c]+ "\t ");
		 
		 }
	//	this.textArea.append("\n");
	 }
 // this.textArea.append("tran：");
   for(r=0;r<bRows;++r){
		for (c = 0; c < bCols; ++c){
			tb[c][r]=bs[r][c];
	//		this.textArea.append(tb[c][r]+"\t");
		}
	//	this.textArea.append("\n");
	}
  // this.textArea.append("chengji:");
   for (  i = 0; i < bCols; ++i){
   for ( c = 0; c < bCols; ++c) {
	   tbs[i][c] = 0;
         for ( r= 0; r< bRows; ++r) 
			tbs[i][c] += tb[i][r]*bs[r][c]  ;
		 //this.textArea.append(tbs[i][c]+" ");
				  }
   //this.textArea.append("adsf");
  	}
 // 样本协方差矩阵的一个无偏估计
   for(i=0;i<aCols;++i){
	   for(c=0;c<aCols;++c){
		   yanshi_g1_s[i][c]=(tas[i][c]+tbs[i][c])/(aRows+bRows-2);
		   this.textArea.append(form.format(yanshi_g1_s[i][c])+"\t");}
	   this.textArea.append("\n");
   }
	return yanshi_g1_s;
}

//线形判别函数W(x)的估计
public void panbie(double [][] a,int nRows,int nCols,double[]b,double[]c)
{       int i,j=0;
		int n=3;
		double p=0.0;
			double l=0.0;
		d1r1F g= new d1r1F ();
		double a1[] = new double [10];
        double b1[] = new double [4];
		double c1[] = new double [3];
		
		for(i=0;i<=n-1;i++){
			for(j=0;j<=n-1;j++){
				a1[i*n+j]=a[i][j];
				
			}
			b1[i]=b[i]-c[i];
		}
		
		g.gaussj (a1,n,b1);
		
		for(i=0;i<=n-1;i++){
			
			c1[i]=(b[i]+c[i])/2;
		}
		
		 for (  i = 0; i < 3; ++i){
   
			p += b1[i]*c1[i]  ;
				  }
	this.textArea.append("W(x)="+form.format(b1[0])+"*x1+"+form.format(b1[1])+"*x2+"+form.format(b1[2])
						 +"*x3-"+form.format(p)+"\n");
	
	this.textArea.append("\n待判样品:\n"+daipan[0]+"  "+daipan[1]+"  "+daipan[2]+" ");
	for(i=0;i<3;i++){
		l +=b1[i]*daipan[i];}
	l=l-p;
		
	this.textArea.append("\n判别函数W(X)的值:\n"+l+"\n");
	if(l<0)
		this.textArea.append("判归类别:"+"2");
	else
	    this.textArea.append("判归类别:"+"1");
	
}

}