本文共 6247 字，大约阅读时间需要 20 分钟。

Java GUI实战：Swing 实现可视化马尔可夫决策（二）

核心算法

基于马尔可夫决策过程的强化学习算法

对于一个节点（视为一个状态），它有四个后继。每迭代一次，它的状态值更新为四个期望值中最大的那个

马尔可夫决策代码

public static void nextValues(double[] values,double[] rewards,double gamma){
        double[] newVal = new double[25];     for(int i=0;i<5;i++){
            for(int j=0;j<5;j++){
                int k = i*5+j;             if(rewards[k]==1||rewards[k]==-1||rewards[k]==2)                 newVal[k]=0;             else{
                    double up=0;                 double down=0;                 double left = 0;                 double right = 0;                 //up                 if(checkBorder(i-1,j-1)&&rewards[k-6]!=2) {
                        up += 0.2 * (gamma*values[k - 6]+rewards[k-6]);                     left+=0.2*(gamma*values[k-6]+rewards[k-6]);                 }                 else {
                        up += 0.2 * (gamma*values[k]+rewards[k]);                     left+=0.2*(gamma*values[k]+rewards[k]);                 }                 if(checkBorder(i-1,j)&&rewards[k-5]!=2)                     up+=0.6*(gamma*values[k-5]+rewards[k-5]);                 else                     up+=0.6*(gamma*values[k]+rewards[k]);                 if(checkBorder(i-1,j+1)&&rewards[k-4]!=2) {
                        up += 0.2 * (gamma*values[k - 4]+rewards[k-4]);                     right+=0.2*(gamma*values[k-4]+rewards[k-4]);                 }                 else {
                        up += 0.2 * (gamma*values[k]+rewards[k]);                     right+=0.2*(gamma*values[k]+rewards[k]);                 }                 //down                 if(checkBorder(i+1,j-1)&&rewards[k+4]!=2) {
                        down += 0.2 * (gamma*values[k + 4]+rewards[k+4]);                     left+=0.2*(gamma*values[k+4]+rewards[k+4]);                 }                 else {
                        down += 0.2 * (gamma*values[k]+rewards[k]);                     left+=0.2*(gamma*values[k]+rewards[k]);                 }                 if(checkBorder(i+1,j)&&rewards[k+5]!=2)                     down+=0.6*(gamma*values[k+5]+rewards[k+5]);                 else                     down+=0.6*(gamma*values[k]+rewards[k]);                 if(checkBorder(i+1,j+1)&&rewards[k+6]!=2) {
                        down += 0.2 * (gamma*values[k + 6]+rewards[k+6]);                     right+=0.2*(gamma*values[k+6]+rewards[k+6]);                 }                 else {
                        down += 0.2 * (gamma*values[k]+rewards[k]);                     right+=0.2*(gamma*values[k]+rewards[k]);                 }                 //left                 if(checkBorder(i,j-1)&&rewards[k-1]!=2)                     left+=0.6*(gamma*values[k-1]+rewards[k-1]);                 else                     left+=0.6*(gamma*values[k]+rewards[k]);                 //right                 if(checkBorder(i,j+1)&&rewards[k+1]!=2)                     right+=0.6*(gamma*values[k+1]+rewards[k+1]);                 else                     right+=0.6*(gamma*values[k]+rewards[k]);                 newVal[k]=maxInFour(up,down,left,right);             }         }     }    System.arraycopy(newVal, 0, values, 0, 25);} public static boolean checkBorder(int i,int j){
        return 0<=i&&i<=4&&0<=j&&j<=4; } public static double maxInFour(double d1,double d2,double d3,double d4){
        double result = d1;     if(result

绑定NEXT按钮

next.addActionListener(new ActionListener() {
       @Override    public void actionPerformed(ActionEvent e) {
           //CalcuNext cal = new CalcuNext();        nextValues(values,rewards,gammaa[0]);        for(int i=0;i<25;i++)            if(rewards[i]==1||rewards[i]==-1){
                   grids.get(i).setText(rewards[i]+"");            }else {
                   grids.get(i).setText(values[i] + "");            }        count[0]++;        showN.setText(count[0]+"");    }});

自定义地图

edit.addActionListener(new ActionListener() {
       @Override    public void actionPerformed(ActionEvent e) {
           int x = Integer.parseInt(editX.getText());        int y = Integer.parseInt(editY.getText());        int attr = Integer.parseInt(editAttr.getText());//0 for empty,1 for enter,2 for exit, 3 for gold, 4 for hole, 5 for stone        switch (attr){
               case 0:                values[x*5+y]=0;                rewards[x*5+y]=0;                grids.get(x*5+y).setBackground(Color.white);                break;            case 1:                values[x*5+y]=0;                rewards[x*5+y]=0;                grids.get(x*5+y).setBackground(Color.BLUE);                startIndex[0]=x*5+y;                      //there should be only one start!                break;            case 2:                values[x*5+y]=0;                rewards[x*5+y]=1;                grids.get(x*5+y).setBackground(Color.RED);                break;            case 3:                values[x*5+y]=0;                rewards[x*5+y]=0.25;                grids.get(x*5+y).setBackground(Color.YELLOW);                break;            case 4:                values[x*5+y]=0;                rewards[x*5+y]=-1;                grids.get(x*5+y).setBackground(Color.GRAY);                break;            case 5:                values[x*5+y]=2;                rewards[x*5+y]=2;                grids.get(x*5+y).setBackground(Color.BLACK);            default:                break;        }        for(int i=0;i<25;i++)            if(rewards[i]==1||rewards[i]==-1)                grids.get(i).setText(rewards[i]+"");            else {
                   grids.get(i).setText(values[i] + "");            }    }});

REPLAY按钮

restart.addActionListener(new ActionListener() {
       @Override    public void actionPerformed(ActionEvent e) {
           for(int i=0;i<25;i++){
               values[i]=0;            rewards[i]=0;            grids.get(i).setBackground(Color.white);            grids.get(i).setText("0.0");        }        count[0]=0;        stepCount[0]=0;        showN.setText(count[0]+"");        stepCountShow.setText(stepCount[0]+"");        edit.setEnabled(true);        next.setEnabled(false);    }});

转载地址：http://hywai.baihongyu.com/