分段线性插值.cpp

数值分析程序。。。。。好多程序下载 喜欢的朋友可以下 随时欢迎

#include<iostream.h>
void main()
{
	double x,y;
	double a[4]={0.46,0.47,0.48,0.49,};
	double b[4]={0.4846555,0.4937452,0.5027498,0.5116683};
	int i;
	cout<<"请输入所插结点x的值"<<endl;
	cin>>x;
	if(x<a[0])
	{
		i=1;
		goto L;
	}
	else
		if(x>a[0]&&x<a[3])
		{
			for(i=1;i<3;i++)
				if(x<a[i])
					goto L;
		}
		else i=4;
    L:
		y=(x-a[i])/(a[i-1]-a[i])*b[i-1]+(x-a[i-1])/(a[i]-a[i-1])*b[i];
		cout<<y<<endl;
}