#include"math.h"
#include"stdio.h"
#include<stdio.h>
main()
{    
     FILE *fpi;
     FILE *fpo;

        float rd[5];
        float pt[5];
        float tr[5];
        float step; 

           step=0.005;                  /*在此設定篩選步長*/

        int i,j; 
      if((fpi=fopen("c:\\myd\\1.txt","r"))==NULL)    /*請在“”內輸入要處理的文件*/
         {printf("Can not open this file!");
          exit(0);
          } 
      fpo=fopen("c:\\myd\\2.txt","a");              /*請在“”內輸入存放結果的文件*/


        for(i=0;i<10;i++)
         {  fread(rd,4,5,fpi);
            if(((fabs(rd[2]-pt[2]))>step)||((fabs(rd[3]-pt[3]))>step))
             { for(j=0;j<5;j++)
                   pt[j]=rd[j];

               fwrite(rd,4,5,fpo);              

              }         
                         }

     fclose(fpi);
     fclose(fpo);

    exit(0); 


    getch();    /* 請不要刪除此行 */
}