牛顿切线法.cpp

这是计算方法上的所有算法

#include "math.h"
#include "stdio.h"
#include "iostream.h"
#define MaxK 1000
#define EPS 0.5e-3
double f(double x){return x*x*x-x-1;}
double f1(double x){return 3*x*x-1;}

void main()
{
	double x=1.5;
	int newton(double(*)(double),double(*)(double),double &x0,double);
	if(newton(f,f1,x,EPS)==1)
		printf("the root is x=%f \n",x);
	else printf("the method is fail!");	
}

int newton(double (*f)(double),double(*f1)(double),double &x0,double eps)
{
	int i=0,k=0;
	double x1=x0,T=0.0000;
	cout<<"****牛顿切线法****"<<endl;  
	cout<<"k"<<"       "<<"xk"<<endl;
	cout<<"------------------------"<<endl;
	cout<<i<<"      "<<x0<<endl;
	do
	{
		x0=x1;
	    x1=x0-f(x0)/f1(x0);
	    cout<<++i<<"      "<<x1<<endl;
		T=x1-x0;
		T=fabs(T); 
	}while(T>=eps); 
	cout<<"------------------------"<<endl;
	if(i>0){k=1;}
    return k;
}