Howto get a centroid of a section in a slice?

[jumbojing]

@lassoan

import numpy as np
print(np.average(array('ModelX'), axis=0))

老师您的意思👆🏻是说，多边形各顶点坐标的`np.average()'就是这个多边形的质心吗？

Teacher, do you mean that the `np.average()’ of the coordinates of each vertex of the polygon is the centroid of the polygon?