计算机视觉 openCV2 几种fitting line 方法

1. 最小二乘法（least square）：

x = []
y = []
for point in data_points:
    x.append(point[0])
    y.append(point[1])
avg_x = (sum(x)) / len(x)
avg_y = (sum(y)) / len(y)
x_sub = list(map((lambda x: x - avg_x), x))
y_sub = list(map((lambda y: y - avg_y), y))
x_sub_pow2 =