d5r2.cpp

visual c++查过能用数值算法 附带光盘里面的源代码

#include "iostream.h"
#include "math.h"

void main()
{
    //program d5r2
    //driver for routine ddpoly
    //polynomial (x-1)^5
    char *a[6];
    int i,j,nc = 6;
    int ncm1 = 5;
    int np = 20;
	double aaa,x;
    double c[7], pd[6], d[6][21];
    a[1] = "polynomial:";
    a[2] = "first deriv:";
    a[3] = "second deriv:";
    a[4] = "third deriv:";
    a[5] = "fourth deriv:";
    c[1] = -1.0;
    c[2] = 5.0;
    c[3] = -10.0;
    c[4] = 10.0;
    c[5] = -5.0;
    c[6] = 1.0;
    for (i = 1; i<=np; i++)
	{
        x = 0.1 * i;
        ddpoly(c, nc, x, pd, nc - 1);
        for (j = 1; j<=nc - 1; j++)
		{
            d[j][i] = pd[j];
        }
    }
	cout.setf(ios::fixed|ios::right);
	cout.precision(6);
    for (i = 1; i<=nc-1; i++)
	{
        cout<<a[i]<<endl;
        cout<<"          x          ddpoly       actual"<<endl;
        for (j = 1; j<=np; j++)
		{
            x = 0.1 * j;
			cout.width(14);
            cout<<x;
			cout.width(14);
            cout<<d[i][j];
            aaa = factrl(nc - 1) / factrl(nc - i) * (pow((x - 1.0) , (nc - i)));
			cout.width(14);
            cout<<aaa<<endl;
        }
        cout<<endl;
    }
}