d4r12.h

Visual C++ 常用数值算法集 源代码

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

double ERFCC(double X)
{
	double Z,T,DDD,AAA,BBB,CCC,temp;
    Z = fabs(X);
    T = 1.0 / (1.0 + 0.5 * Z);
    DDD = -0.82215223 + T * 0.17087277;
    AAA = T * (-1.13520398 + T * (1.48851587 + T * DDD));
    BBB = T * (-0.18628806 + T * (0.27886807 + AAA));
    CCC = T * (0.37409196 + T * (0.09678418 + BBB));
    temp= T * Exp(-Z * Z - 1.26551223 + T * (1.00002368 + CCC));
    if (X < 0.0) 
		temp= 2.0 - temp;
	return temp;
}

void main()
{
    //PROGRAM D4R2
    //Driver for routine FACTRL
    int I;
	char Text[20];
    double NVAL,ACTUAL,X; 
    const double PI = 3.1415926;
    fstream fin;
    fin.open("e:\\VB常用数值算法集\\DATA\\FNCVAL.DAT",ios::in);
    while (strcmp(Text,"Error")!=0)
	{
      //Text[0]=0;
      fin>>Text;
	}
	fin>>Text;
    fin>>NVAL; 
    cout<<Text<<" "<<endl;
    fin>>Text;
    cout<<endl;
    cout<<"    X        Actual       ERF(X)"<<endl;

    for( I = 1;I<=NVAL;I++)
	{
        fin>>X;
		fin>>ACTUAL; 
		ACTUAL=1-ACTUAL;
		cout<<setw(1)<<X;
		cout<<setw(18)<<ACTUAL;
		cout<<setw(18)<<ERFCC(X)<<endl;			          
    }
}