d7r4.cpp

数值计算c++源代码,包括各种算法。很有用的。

#include "iostream.h"
#include "fstream.h"
#include "stdlib.h"

void sort(int n, double ra[])
{
    int i,j,l,ir;
	double rra;
	l = int(n / 2) + 1;
    ir = n;
    do
	{
        if (l > 1)
		{
            l = l - 1;
            rra = ra[l];
		}
        else
		{
            rra = ra[ir];
            ra[ir] = ra[1];
            ir = ir - 1;
            if (ir == 1)
			{
              ra[1] = rra;
              return;
            }
        }
        i = l;
        j = l + l;
        while (j <= ir)
		{
            if (j < ir)
			{
                if (ra[j] < ra[j + 1])
				{
					j+=1;
				}
            }
            if (rra < ra[j])
			{
                ra[i] = ra[j];
                i = j;
                j += j;
			}
            else
			{
                j = ir + 1;
            }
        }
        ra[i] = rra;
    }while(1);
}

void main()
{
    //program d7r4
    //for routine sort
    double a[101];
	int i,j;
	ifstream fin;
	fin.open("d:\\vc常用数值算法集\\data\\tarray.dat",ios::in|ios::nocreate);
	if (!fin)
	{
		cerr<<"could not open d:\\vc常用数值算法集\\data\\tarray.dat"<<endl;
		exit(1);
	}
	for (i=1; i<=100; i++)
	{
		fin>>a[i];
	}
	fin.close();
    //print original array
    cout<<"Original array:"<<endl;
	cout<<endl;
    for (i = 1; i<=10; i++)
	{
        for (j = 1; j<=10; j++)
		{
			cout.width(7);
			cout.setf(ios::left);
            cout<<a[10 * (i - 1) + j];
        }
        cout<<endl;
    }
    //sort array
    sort(100, a);
    //print sorted array
	cout<<endl;
    cout<<"Sorted array:"<<endl;
	for (i = 1; i<=10; i++)
	{
        for (j = 1; j<=10; j++)
		{
			cout.width(7);
			cout.setf(ios::left);
            cout<<a[10 * (i - 1) + j];
        }
        cout<<endl;
    }
}