java EM算法

学习吧，总会有厌倦期，EM算法就不自己写了，转帖一个源码，可运行，个人不喜欢算法的图形界面，所以这个算法也没怎么研究，但是可运行。转载的最初链接无从查起，如有侵权，请与我联系，带来不便，敬请谅解。不多啰嗦，直接上源码（个人感觉EM算法的高斯混合模型好难- -、）

import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;

import java.lang.Math;
import java.text.DecimalFormat;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;


public class MachineTranslation{
    private static final long serialVersionUID = 2904270580467455923L;
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                Display frame = new Display();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setVisible(true);
            }
        });
    }
}

class Display extends JFrame {
    private static final int DEFAULT_WIDTH = 532;
    private static final int DEFAULT_HEIGHT = 508;
    
    private JTextField textField_3;
    private JTextField textField_2;
    private JTextField textField_1;
    private static final long serialVersionUID = -2794537679802534502L;
    
    private JTable table;
    private JTextField textField;
    private final JButton emButton;
    
    public Display() {
        super();
        getContentPane().setLayout(null);
        setSize(DEFAULT_WIDTH,DEFAULT_HEIGHT);
        

        textField = new JTextField("<HHH>,<TTT>,<HHH>,<TTT>");
        textField.setBounds(61, 42, 237, 33);
        getContentPane().add(textField);

        emButton = new JButton();
        emButton.setText("EM");
        emButton.setBounds(344, 44, 106, 28);
        getContentPane().add(emButton);


        final JLabel wLabel = new JLabel();
        wLabel.setText("λ");
        wLabel.setBounds(61, 98, 25, 18);
        getContentPane().add(wLabel);

        final JLabel p1Label = new JLabel();
        p1Label.setText("P1");
        p1Label.setBounds(198, 98, 25, 18);
        getContentPane().add(p1Label);

        final JLabel p2Label = new JLabel();
        p2Label.setText("P2");
        p2Label.setBounds(349, 98, 25, 18);
        getContentPane().add(p2Label);

        textField_1 = new JTextField();
        textField_1.setText("0.3");
        textField_1.setBounds(86, 96, 87, 22);
        getContentPane().add(textField_1);

        textField_2 = new JTextField();
        textField_2.setText("0.3");
        textField_2.setBounds(229, 96, 87, 22);
        getContentPane().add(textField_2);

        textField_3 = new JTextField();
        textField_3.setText("0.6");
        textField_3.setBounds(380, 96, 87, 22);
        getContentPane().add(textField_3);
        
        setTitle("掷硬币EM算法之实现");
        
        Toolkit tk =this.getToolkit();//得到窗口工具条
        Dimension dm = tk.getScreenSize();
        this.setLocation((int)(dm.getWidth()-DEFAULT_WIDTH)/2,(int)(dm.getHeight()-DEFAULT_HEIGHT)/2);//显示在屏幕中央

        
        emButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                EmAlgorithm em = new EmAlgorithm(textField.getText(),textField_1.getText(),textField_2.getText(),textField_3.getText());
                em.maximizeExpectation();
                final JScrollPane scrollPane = new JScrollPane();
                scrollPane.setBounds(37, 121, 453, 261);
                getContentPane().add(scrollPane);

                table= new JTable(em.getCells(),em.getColumnNames());
                scrollPane.setViewportView(table);
                System.out.println(1E-300-1E-301>0);
            }
        });
    }
}

class EmAlgorithm{
    private String str;
    private ArrayList<Sub> sub=new ArrayList<Sub>();
    private ArrayList<Double> w=new ArrayList<Double>();
    private ArrayList<Double> P1=new ArrayList<Double>();
    private ArrayList<Double> P2=new ArrayList<Double>();
    private ArrayList<ArrayList<Double>> p;
    
    private Object[][] cells;
    private String[] columnNames;

    public EmAlgorithm(String str, String str1,String str2, String str3){
        this.str=str;
        w.add(Double.parseDouble(str1));
        P1.add(Double.parseDouble(str2));
        P2.add(Double.parseDouble(str3));

        textSplit();    
        p=new ArrayList<ArrayList<Double>>();
        for(int j = 0; j < sub.size(); ++j)
            p.add(new ArrayList<Double>());
        System.out.println(p);
    }
    public void textSplit(){
        String[] sList;
        sList=str.substring(1,str.length()-1).split(">,<");

        for (int i = 0; i < sList.length; i++){
            sub.add(new Sub(sList[i]));
        }
        System.out.println(sub);
    }
    public void maximizeExpectation(){
        int iterate=0;
        if (!P1.get(P1.size() - 1).equals(P2.get(P2.size() - 1))) {
            do {
                iterate++;
                compute();
            } while (Math.abs(P1.get(P1.size() - 1) - P1.get(P1.size() - 2)) > 0.0000001);
            // }while(Math.abs(P1.get(P1.size()-1)-P1.get(P1.size()-2))>1.E-300);
        }
        else{
            iterate=7;
            for(int i=0;i<iterate;i++){
                compute();
            }
        }
        cells=new Object[p.get(0).size()][4+sub.size()];
        
        DecimalFormat df_t=new DecimalFormat("0.0000");
        
        for(int i=0;i<iterate;i++){
            cells[i][0]=i;
            cells[i][1]=df_t.format(w.get(i));
            cells[i][2]=df_t.format(P1.get(i));
            cells[i][3]=df_t.format(P2.get(i));
            for(int j=0;j<sub.size();j++){
                cells[i][j+4]=df_t.format(p.get(j).get(i));
            }
        }
        columnNames=new String[4+sub.size()];
        columnNames[0]="Iteration";
        columnNames[1]="w";
        columnNames[2]="P1";
        columnNames[3]="P2";
        for(int i=0;i<sub.size();i++)
            columnNames[i+4]="p"+(i+1);
    }
    public void compute(){
        double w=this.w.get(this.w.size()-1);
        double P1=this.P1.get(this.P1.size()-1);
        double P2=this.P2.get(this.P2.size()-1);
        //System.out.println(w+","+P1+","+P2+"     "+this.w.size());
        for (int i = 0; i < sub.size(); i++) {
            float PP1 = (float) Math.pow(P1, sub.get(i).getH())
                    * (float) Math.pow(1 - P1,sub.get(i).getT());
            float PP2 = (float) Math.pow(P2, sub.get(i).getH())
                    * (float) Math.pow(1 - P2, sub.get(i).getT());
            p.get(i).add(w * PP1 / (w * PP1 + (1 - w) * PP2));
        }
        double sump=0;
        double sumP1=0;
        double sumP2=0;float sumpp=0;
        
        for(int i=0;i<sub.size();i++){
            sump+=p.get(i).get(p.get(i).size()-1);
            sumP1+=(sub.get(i).getH()/3.0)*p.get(i).get(p.get(i).size()-1);
            sumP2+=(sub.get(i).getH()/3.0)*(1-p.get(i).get(p.get(i).size()-1));
            sumpp+=(1-p.get(i).get(p.get(i).size()-1));
        }
        this.w.add(sump/sub.size());
        this.P1.add(sumP1/sump);
        this.P2.add(sumP2/sumpp);
    }
    public Object[][] getCells(){
        return cells;
    }
    public String[] getColumnNames(){
        return columnNames;
    }
}
class CountHT{
    private int hCount=0;
    private int tCount=0;
    
    public CountHT(String str){
        char[] temp=str.toCharArray();
        for(int j=0;j<temp.length;j++){
            if(temp[j]=='H'){
                hCount++;
                continue;
            }
            if(temp[j]=='T'){
                tCount++;
                continue;
            }
            System.out.println("输入有问题");
        }    
    }
    public int getH(){
        return hCount;
    }
    public int getT(){
        return tCount;
    }
}

class Sub{
    private String str;
    private int hCount;
    private int tCount;
    
    public Sub(String str){
        this.str=str;
        CountHT countHT=new CountHT(str);
        hCount=countHT.getH();
        tCount=countHT.getT();
    }
    public String toString(){
        return str+" "+"hCount="+hCount+" "+"tCount="+tCount;
    }
    public int getH(){
        return hCount;
    }
    public int getT(){
        return tCount;
    }
}