C语言实现knn

以后写代码一定要谨慎，提高代码的正确率。

/***************************************
 * 1.初始化距离为最大值
 * 2.计算未知样本和每个训练样本的距离为dist
 * 3.得到目前k个最邻近样本中的最大距离maxdist
 * 4.如果dist小于maxdist，则将改训练样本作为k-最近邻样本
 * 5.重复2、3、4，直至未知样本和训练样本的距离都算完
 * 6.统计k个最近邻样本中每个类别出现的次数
 * 7.选择出现频率最大的类别作为未知样本的类别
 * *****************************************/

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#define MAX 0x7fffffff
#define K 3

double  cal_dist(int n,double *x,double *y)
{
    double sum = 0.0;
    int i =;
    for(i=;i<n;i++)
    {
        sum += pow((x[i]-y[i]),2.0);
    }
    return sqrt(sum);
}

void bubbleSort(double **array,int count,int flag)
{
    int i = count,j;
    double temp;
    while(i>)
    {
        for(j=;j<i-;j++)
        {
            if(flag == )
            {
                if(array[][j] > array[][j+])
                {
                    temp = array[][j];
                    array[][j] = array[][j+];
                    array[][j+] = temp;
                    temp = array[][j];
                    array[][j] = array[][j+];
                    array[][j+] = temp;
                }

            }
            else if(flag == )
            {
                if(array[][j] > array[][j+])
                {
                    temp = array[][j];
                    array[][j] = array[][j+];
                    array[][j+] = temp;
                    temp = array[][j];
                    array[][j] = array[][j+];
                    array[][j+] = temp;
                }
            }
        }
        i--;
    }
    return;
}
int main()
{
    int n,m;
    FILE *fp;
    fp = fopen("/data.txt","r");
    fscanf(fp,"N=%d,D=%d",&n,&m);
    printf("N=%d,D=%d\n",n,m);
    double  **array;
    array = (double **)malloc(n*sizeof(double));
    array[] = (double *)malloc(n*m*sizeof(double));
    int h,j = ,i =;
    for(i=;i<n;i++)
    {
        array[i] = array[i-] + m;
    }
    for(i=;i<n;i++)
    {
        for(j=;j<m;j++)
        {
            fscanf(fp,"%lf",&array[i][j]);
        }
    }
    double **temp;
    temp = (double **)malloc(*sizeof(double));
    temp[] = (double *)malloc(*K*sizeof(double));
    for(i=;i<;i++)
    {
        temp[i] = temp[i-] + K;
    }
    for(i=;i<;i++)
    {
        for(j=;j<K;j++)
        {
            temp[i][j] = MAX*0.1;
        }
    }
    double *testdata;
    double max_dist = 0.0;
    double distance = 0.0;
    double tmp = 0.0;
    testdata=(double *)malloc((m-)*sizeof(double));
    printf("input test data containing %d numbers:\n",m-);
    for(i=;i<(m-);i++)
    {
            fscanf(fp,"%lf",&testdata[i]);
    }
    close(fp);
    while()
    {
        for(i=;i<K;i++)
        {
            if(K > n) break;
            temp[][i] = cal_dist(n,testdata,array[i]);
            temp[][i] = array[i][m-];
        }
        for(i=;i<K;i++)
        {
            printf("%4lf,%4lf\n",temp[][i],temp[][i]);
        }
        printf("\n");
        bubbleSort(temp,K,);
        max_dist = temp[][K-];
        for(i=K;i<n;i++)
        {
            distance = cal_dist(n,testdata,array[i]);
            if(max_dist > distance)
            {
                for(j=;j<K;j++)
                {
                    if(distance < temp[][j])
                    {
                        for(h=K-;h>j;h--)
                        {
                            temp[][h] = temp[][h-];
                            temp[][h] = temp[][h-];
                        }
                    }
                    temp[][j] = distance;
                    temp[][j] = array[i][m-];
                }
            }
            max_dist = temp[][K-];
        }
        bubbleSort(temp,K,);
        break;
    }

    int value_label = ;
    int count = ;
    int flag = ;
    for(i=;i<K-;i++)
    {
        if(temp[][i] != temp[][i+])
        {
            if(flag > count)
            {
                flag = count;
                value_label = temp[][i];
                count =;
            }
        }
        else
        {
            count ++;
        }
    }
    if(count > flag)
    {
        value_label = temp[][K-];
        flag = count;
    }
    printf("Predict message is %d\n",value_label);
    return ;
}