server/KNN/KNN.cpp

//#include "stdafx.h"

#include<iostream>  
#include<map>  
#include<vector>  
#include<stdio.h>  
#include<cmath>  
#include<cstdlib>  
#include<algorithm>  
#include<fstream>  
#include "./../CSVparser/CSVparser.h"
#include "KNN.h"

using namespace std;


ifstream fin;  
ofstream fout;  

string Trim(string& str)
{
 str.erase(0,str.find_first_not_of(" \t\r\n"));
 str.erase(str.find_last_not_of(" \t\r\n") + 1);
 return str;
}

KNN::KNN(int magic_x, int magic_y, int magic_z)  
{  
	int k = 10;
    this->k = k;  

	csv::Parser file = csv::Parser("d:/magic_map/trainning_data_magic.csv");  
  
    std::cout << file[0][0] << std::endl; // display : 1997  
    std::cout << file[0] << std::endl; // display : 1997 | Ford | E350
	cout<<file[1]<<endl;
	int row_count = file.rowCount();
    /* input the dataSet */   
    for(int i=0;i<rowLen;i++)  
    {  
        for(int j=0;j<colLen;j++)  
        {  
			if(i < row_count)
			{
				dataSet[i][j] = atof((file[i][j]).c_str()); 
			}
        }  
        
		if(i < row_count)
		{
			labels[i].x = atof((file[i][3]).c_str());
		    labels[i].y = atof((file[i][4]).c_str());
		}
		
    }  
  
    cout<<"please input the test data :"<<endl;  
    /* inuput the test data */  
    testData[0] = magic_x;
	testData[1] = magic_y; 
	testData[2] = magic_z; 
}  
  
/* 
 * calculate the distance between test data and dataSet[i] 
 */  
double KNN:: get_distance(tData *d1,tData *d2)  
{  
    double sum = 0;  
    for(int i=0;i<colLen;i++)  
    {  
        sum += pow( (d1[i]-d2[i]) , 2 );  
    }  
  
//  cout<<"the sum is = "<<sum<<endl;  
    return sqrt(sum);  
}  
  
/* 
 * calculate all the distance between test data and each training data 
 */  
void KNN:: get_all_distance()  
{  
    double distance;  
    int i;  
    for(i=0;i<rowLen;i++)  
    {  
        distance = get_distance(dataSet[i],testData);  
        //<key,value> => <i,distance>  
        map_index_dis[i] = distance;  
    }  
  
    //traverse the map to print the index and distance  
    map<int,double>::const_iterator it = map_index_dis.begin();  
    while(it!=map_index_dis.end())  
    {  
        //cout<<"index = "<<it->first<<" distance = "<<it->second<<endl;  
        it++;  
    }  
}  
  
/* 
 * check which label the test data belongs to to classify the test data  
 */  
tLabel KNN:: get_max_freq_label()  
{  
    //transform the map_index_dis to vec_index_dis  
    vector<PAIR> vec_index_dis( map_index_dis.begin(),map_index_dis.end() );  
    //sort the vec_index_dis by distance from low to high to get the nearest data  
    sort(vec_index_dis.begin(),vec_index_dis.end(),CmpByValue());  
  
    for(int i=0;i<k;i++)  
    {  
        cout<<"the index = "<<vec_index_dis[i].first<<" the distance = "<<vec_index_dis[i].second<<" the label x= "<<labels[vec_index_dis[i].first].x<<" the label y= "<<labels[vec_index_dis[i].first].y<<" the coordinate ( "<<dataSet[ vec_index_dis[i].first ][0]<<","<<dataSet[ vec_index_dis[i].first ][1]<<" )"<<endl;  
        //calculate the count of each label  
        map_label_freq[ labels[ vec_index_dis[i].first ]]++;
    }  
  
    map<tLabel,int>::const_iterator map_it = map_label_freq.begin();  
    tLabel label;  
    int max_freq = 0;  
    //find the most frequent label  
    while( map_it != map_label_freq.end() )  
    {  
        if( map_it->second > max_freq )  
        {  
            max_freq = map_it->second;  
            label = map_it->first;  
        }  
        map_it++;  
    }  
    cout<<"The test data belongs to the x:"<<label.x<<"y:"<<label.y<<" label"<<endl; 
	return label;
}  

#if 0
int main()  
{  
    int k ;  
    cout<<"please input the k value : "<<endl;  
    cin>>k;  
    KNN knn(k);  
    knn.get_all_distance();  
    knn.get_max_freq_label();  
    system("pause");   
    return 0;  
}
#endif