why the setting is this

[kytimmylai]

https://github.com/ifzhang/FairMOT/blob/ca78d3f01d1953c3d72ee8b01f24a5ddec2689c3/src/lib/tracking_utils/kalman_filter.py#L107

According to the previous illustration, mean[3] should be "height", but why the element i of std almost were assigned to be mean[3], instead of mean[i]?

[shinaushin]

Also interested in this