RL强化学习 C++实现

详细过程见：
http://blog.csdn.net/u013405574/article/details/50903987

#include "iostream"
#include "vector"
#include "string.h"
#include "time.h"
#include "stdlib.h"
#include "stdio.h"
using namespace std;

#define N 6

double Q[N][N];            //状态-动作值函数
double gamma = 0.8;        //折算因子
int finalState = 5;        //最终状态  
int epoches = N;           //训练次数
//回报
double R[N][N] =  
{
    {-1, -1, -1, -1,  0, -1},
    {-1, -1, -1,  0, -1, 100},
    {-1, -1, -1,  0, -1, -1},
    {-1,  0,  0, -1,  0, -1},
    { 0, -1, -1,  0, -1, 100},
    {-1,  0, -1, -1,  0, 100}
};

void RL()
{

    //初始化Q矩阵为0
    memset(Q, 0, sizeof(Q));

    int i, j;

    for(i=0; iif(R[finalState][i] >= 0)
            Q[finalState][i] = R[finalState][i];

    int epoch = 0;
    while(epoch++ < epoches)               //训练次数
    {
        int nowState = rand() % N;         //随机选择一个初始状态
        int step = 0;
        while(step++ < N)                  //如果没有走完
        {
            vector<int> nextAction;        
            for(i=0; iif(R[nowState][i] >= 0)     //下一个可能的动作
                {
                    nextAction.push_back(i); 
                }
            }
            int ns = nextAction[ rand() % nextAction.size() ];   //随机选择到达下一个状态的动作
            double nextQmax = Q[ns][0];
            for(i=1; i//搜寻下一个状态的最大Q值
            {
                if(Q[ns][i] > nextQmax)
                {
                    nextQmax = Q[ns][i];
                }
            }

            //最为核心的地方：
            //Q(state, action) = R(state, action) + Gamma * Max[Q(next state, all actions)]
            Q[nowState][ns] = R[nowState][ns] + gamma * nextQmax;   

            nowState = ns;                  //更新当前状态
        }

        //为了使Q值不要太大
        if(epoch % 10 == 0)
        {
            double min = 10000;
            for(i=0; ifor(j=0; jif(Q[i][j] < min && Q[i][j] > 0)
                        min = Q[i][j];
            }
            for(i=0; ifor(j=0; jvoid printSolution(int startState)
{
    while(startState < finalState)
    {
        cout << startState << "-->";
        double maxQnext = -1;
        int nextAction = 0;
        for(int i=0; iif(R[startState][i] >= 0)   //如果下一个状态可达
            {
                if(Q[startState][i] > maxQnext)
                {
                    maxQnext = Q[startState][i];
                    nextAction = i;
                }
            }
        }
        //cout << nextAction;
        startState = nextAction;
    }
    cout << finalState << endl;
}

int main()
{
    srand(time(NULL));

    RL();

    for(int i=0; ifor(int j=0; jprintf("%.1f\t ", Q[i][j]);
        cout << endl;
    }

    while(1)
    {
        cout << "请输入一个初始状态：" << endl;
        int startState;
        cin >> startState;
        cout << "路径为：";
        printSolution(startState);
    }

    return 0;
}

参考
[1] http://blog.csdn.net/u013405574/article/details/50903987
[2] http://www.cnblogs.com/Leo_wl/p/5852010.html