ksxj.cpp

都是计算方法的上机作业

/*该程序功能：据140页快速弦截法解方程。*/
#include "stdafx.h"
#include<math.h>
#include<stdio.h>
#include<iostream.h>
const N=500;
double f(double x)
{
return x*exp(x)-1;
}
double fz(double x0,double x1)
{
	return (x1-x0)/(f(x1)-f(x0));
}

int main(int argc, char* argv[])
{   int k=1;
    double x0,x1,e,temp;
    cout<<"Please enter 3 number:"<<endl;
       cin>>x0>>x1>>e;
    cout<<"The result is:"<<endl;
   while(1)
	{
	  temp=x0;
	     x0=x1;
	       x1=x1-f(x1)*fz(temp,x1);
	 if(k!=N)
     {
	        if(fabs(x1-x0)<e)
			{
		      printf("x=%.5f,n=%d\n",x1,k);
	             return 0;
			}
	         else
	             k++;
	 } 
	 else
	 {
		 cout<<"Fail!"<<endl;
		 return 0;
	 }
   }

}