椭圆拟合的误差算法，拟合点到椭圆心的距离减去拟合点对应在椭圆上的点到椭圆心的距离，有效分析椭圆拟合的误差问题，并让其在对话框中显示出来-The error ellipse fitting algorithm, fitting point to the ellipse center distance minus the corresponding fitting point on the ellipse to the ellipse center point of the distance, th