d10r2.cpp

来自「工程算法 这是一个很有用的工程数值算法集锦」· C++ 代码 · 共 40 行

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

double fun(double x)
{
	double t;
	t=bessj0( x);
	return t;
}

void main()
{
	//program d10r2
    //driver for routine zbrac
	bool succes;
	int i;
	double x1,x2;
    cout<<endl;
    cout<<"  bracketing values:      function values:"<<endl;
    cout<<endl;
    cout<<"     x1      x2      bessj0(x1)    bessj0(x2)";
	cout<<setprecision(2)<<setiosflags(ios::fixed);
    for (i = 1; i<=10; i++)
	{
        x1 = double(i);
        x2 = x1 + 1;
        zbrac(x1, x2, succes);
        if (succes)
		{
            cout<<setprecision(2)<<setw(8)<<x1;
            cout<<setprecision(2)<<setw(8)<<x2;
            cout<<setprecision(6)<<setw(14)<<bessj0(x1);
            cout<<setprecision(6)<<setw(14)<<bessj0(x2);
        }
    }
	cout<<endl;
}