circle_fit

代码说明：

说明：  圆拟合，通过已知的多组数据，拟合出最小误差的圆(Given a set of measured x,y pairs that a re supposed to reside on a circle, but with some added noise. A circle to these points, i.e. find xc,yc,R, such that (x-xc)^2+(y-yc)^2=R^2)