// NaiveBayes.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include < string >
#include < vector >
#include< iostream >
#include< fstream >
#include < math.h >
using namespace std;
int _tmain(int argc, _TCHAR* argv[])
{
vector< vector< float > > descriptor;
vector< float > classes;
ifstream f;
f.open("c:\\bayes.txt");
while(f)
{
string str = "";
f > >str;
vector< float > desc;
size_t found = str.find(",");
while(found< 100 && found >0)
{
string t = str.substr(0,found);
desc.push_back(strtod(t.c_str(), NULL));
str = str.substr(found+1);
found = str.find(",");
}
if(desc.size() >0)
{
descriptor.push_back(desc);
classes.push_back(strtod(str.c_str(), NULL));
}
}
f.close();
//0.51,0.52,0.54,0.51,0.53,0
vector< float > v;
v.push_back(0.51);
v.push_back(0.52);
v.push_back(0.54);
v.push_back(0.51);
v.push_back(0.53);
vector< float > mean1;
mean1.resize(descriptor[0].size());
vector< float > mean2;
mean2.resize(descriptor[0].size());
int nr1 = 0;
int nr2 = 0;
vector< float > disp1;
vector< float > disp2;
disp1.resize(descriptor[0].size());
disp2.resize(descriptor[0].size());
// calcul medie
for(int i=0;i< descriptor.size();i++)
{
if(classes[i] == 0)
{
for(int j=0;j< mean1.size();j++)
{
mean1[j] +=descriptor[i][j];
}
nr1++;
}
else
{
for(int j=0;j< mean1.size();j++)
{
mean2[j] +=descriptor[i][j];
}
nr2++;
}
}
for(int j=0;j< mean1.size();j++)
{
mean1[j] /=nr1;
mean2[j] /=nr2;
}
// calcul dispersie
for(int i=0;i< descriptor.size();i++)
{
if(classes[i] == 0)
{
for(int j=0;j< mean1.size();j++)
{
disp1[j] += (mean1[j] - v[j])*(mean1[j] - v[j]);
}
}
else
{
for(int j=0;j< mean1.size();j++)
{
disp2[j] += (mean2[j] - v[j])*(mean2[j] - v[j]);
}
}
}
for(int j=0;j< mean1.size();j++)
{
disp1[j] = sqrt(disp1[j])/nr1;
disp2[j] = sqrt(disp2[j])/nr2;
}
float r1 = 1;
float r2 = 1;
for(int j=0;j< mean1.size();j++)
{
r1 = r1*((1/disp1[j])*exp( (-1) * (mean1[j] - v[j])*(mean1[j] - v[j])/disp1[j] ));
r2 = r2*((1/disp2[j])*exp( (-1) * (mean2[j] - v[j])*(mean2[j] - v[j])/disp2[j] ));
}
//
}
Tuesday, November 30, 2010
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment