非常感谢你的分享。在讲 geopandas 坐标系时，**地图（geopandas 自带，natural earth 的数据）缺少藏南。Cartopy 也是用的同样地图。建议不要使用 geopandas 自带的地图，改用 shapefile，像你的其它博文里用的那样。

感谢博主优质的内容，请问Dash教程系列的版本是多少呀？

您好作者，我调试了这个程序，发现无法下载路网数据，错误原因可能是https://overpass.kumi.systems/api/interpreter这个网站无法爬到数据，会提示如下信息：
The data included in this document is from www.openstreetmap.org. The data is made available under ODbL.

Error: encoding error: Your input contains only whitespace.
请问您之前在调试程序的时候是否也出现过这个问题呢？

Hi CNFeffery,

Thanks for sharing the knee points detection idea and the paper!

I have 2questions:

1. I've reproduced the whole process using the latest data (to Feb 23), and I found that the detection machine gives a different result in late Feb. With the latest data, the plot shows that there's a convex increasing on Feb 22, instead of the concave decreasing on Feb 18. Is that a bad sign?

2. Why do you set online = False when creating the knee_point_search function?

It would be greatly appreciated if you can help me with the questions!