d14r8.cpp

vc++常用数值算法集合

#include<math.h>
#include<iomanip.h>
#include<iostream.h>
#include<process.h>

void main()
{
    //program d14r8
    //driver for routine pzextr
    //feed values from a rational function
    //fn(x)=(1-x+x**3)/(x+1)**n
	int nv,nuse,i,j,iest;
	double xest,dum;
    nv = 4;
    nuse = 5;
    double  yest[5], yz[5], dy[5];
    for (i = 1; i<=10; i++)
	{
        iest = i;
        xest = 1.0 / float(i);
        dum = 1.0 - xest + pow(xest , 3);
        for (j = 1; j<= nv; j++)
		{
            dum = dum / (xest + 1.0);
            yest[j] = dum;
        }
        pzextr(iest, xest, yest, yz, dy, nv, nuse);
        cout<<endl;
        cout<<"I= "<< i<<endl;
        cout<<"Extrap. function: ";
		cout<<setprecision(6)<<setiosflags(ios::fixed);
        for (j = 1; j<= nv; j++)
		{
            cout<<setw(13)<<yz[j];
        }
		cout<<endl;
        cout<<"Estimated error:  ";
        for (j = 1; j<= nv; j++)
		{
            cout<<setw(13)<<dy[j];
        }
		cout<<endl;
    }
	cout<<endl;
    cout<<"actual values:    "<<setw(13)<<"1.000000";
    cout<<setw(13)<<"1.000000"<<setw(13)<<"1.000000";
	cout<<setw(13)<<"1.000000"<<endl;
}