关于天气分类的贝叶斯预测

#include<iostream>
#include<list>
#include<cstring>
#include<string>
#include<vector>
#include<map>
#include<sstream>
#include<iomanip>
#include<cmath>
#include<fstream>
#include<algorithm>
#include<set>
#include<queue>
using namespace std;

class Bayes
{
private:
	vector<string> attribute;
	vector<vector<string>>data;
	double GetPosPrior()
	{
		int count=0;
		for(vector<vector<string>>::iterator iter=data.begin();iter!=data.end();++iter)
		{
			if((*iter)[4]=="yes")
				count++;
		}
		return (double)count/data.size();
	}
	double GetNegPrior()
	{
		int count=0;
		for(vector<vector<string>>::iterator iter=data.begin();iter!=data.end();++iter)
		{
			if((*iter)[4]=="no")
				count++;
		}
		return (double)count/data.size();
	}
	// 求条件概率
	double ConPro(int attr,string value,bool pos)
	{
		if(pos)
		{
			int count1=0,count2=0;
			for(vector<vector<string>>::iterator iter=data.begin();iter!=data.end();++iter)
			{
				if((*iter)[4]=="yes")
				{
					count1++;
					if((*iter)[attr]==value)
						count2++;
				}
				
			}
			return (double)count2/(count1);
		}
		else
		{
			int count1=0,count2=0;
			for(vector<vector<string>>::iterator iter=data.begin();iter!=data.end();++iter)
			{
				if((*iter)[4]=="no")
				{
					count1++;
					if((*iter)[attr]==value)
						count2++;
				}
				
			}
			return (double)count2/(count1);
		}
	}
public:
	Bayes()
	{
		// 从文件中加载数据
		ifstream in("playData.txt");
		if(in==NULL)
		{
			cout<<"fail to open file!"<<endl;
			return;
		}
		string line,str;
		getline(in,line);
		istringstream istring(line);
		while(!istring.eof())
		{
			istring>>str;
			attribute.push_back(str);
		}
		while(!in.eof())
		{
			getline(in,line);
			vector<string> vecStr;
			istringstream istring(line);
			while(!istring.eof())
			{	
				istring>>str;
				vecStr.push_back(str);
			}
			data.push_back(vecStr);
		}
		in.close();
	}
	// 传递4个元组的例子
	string run(string a[])// 返回贝叶斯的预测结果
	{
		string result;

		double posPr=this->GetPosPrior();
		double negPr=this->GetNegPrior();
		for(int i=0;i<4;i++)
		{
			posPr*=ConPro(i,a[i],true);
			negPr*=ConPro(i,a[i],false);
		}
		if(posPr>negPr)
			result="yes";
		else
			result="no";

		return result;
	}
	
};
	string out[]={"sunny","overcast","rainy"};
	string temp[]={"hot","mild"};
	string humidity[]={"high","hot","normal"};
	string windy[]={"TRUE","FALSE"};
	string *s[]={out,temp,humidity,windy};
	void writeAll()
	{

	}
int main()
{





	Bayes bay;
	string ex[4];
	cin>>ex[0]>>ex[1]>>ex[2]>>ex[3];


	cout<<"分类的结果：";
	cout<<bay.run(ex);
	system("pause");

	return 0;
}