d4r09.cpp

工程算法 这是一个很有用的工程数值算法集锦

#include <iostream.h>
#include <math.h>
#include <iomanip.h>
#include <stdlib.h>
#include <fstream.h>
#include <string>

void main()
{
    //program d4r9
    //driver for routine gcf
    int i;
	char text[20];
    double w,z,value,gammcf,gln,nval; 
    const double pi = 3.1415926;
    fstream fin;
    fin.open("d:\\vc常用数值算法集\\data\\fncval.dat",ios::in);
    while (strcmp(text,"Incomplete")!=0)
	{
      fin>>text;
	}
	fin>>text;
	fin>>text;
    fin>>nval; 
    cout<<"Incomplete Gamma Function "<<endl;
    fin>>text;
    cout<<endl;
    cout<<" a   x    actual    gcf(a,x)   gammln(a)    gln"<<endl;
    for( i = 1;i<=nval;i++)
	{
        fin>>w;
		fin>>z;
		fin>>value; 
        if( z >= w + 1)		
		{
		gcf(gammcf, w, z, gln);
		cout<<setw(4)<<w;
		cout<<setw(11)<<z;
		cout<<setw(12)<<1-value;
        cout<<setw(14)<<gammcf;
        cout<<setw(15)<<gammln(w);
        cout<<setw(15)<<gln<<endl;
		}
    }
}