5_19.cpp

非线性拟和的数值算法 c++实现 希望对大家有用

#include<iostream.h>
class point
{
public:
	double x;
	double y;
};
void main()
{
	int n;
	double ax=0;
	double ay=0;
	double axy=0;
	double ax2=0;
	double a,b;
	cout<<"Plese enter the point number:"<<endl;
    cin>>n;
	cout<<"Plese enter the points:"<<endl;
	point *p=new point[n];
	for(int i=0;i<n;i++)
	{
		cin>>p[i].x>>p[i].y;
		ax=ax+p[i].x;
		ay=ay+p[i].y;
		axy=axy+(p[i].x)*(p[i].y);
		ax2=ax2+(p[i].x)*(p[i].x);
	}
	b=(axy*ax-ay*ax2)/(ax*ax-n*ax2);
	a=(ay-n*b)/ax;
	cout<<"y="<<b;
	if(a>0)
		cout<<"+";
	cout<<a<<"x"<<endl;

	
}