Github tutorial problem

I was following this tutorial on YOLO, and following this guide (this is the GitHub code for the tutorial)
I'm trying to find the coordinates of the center of the bounding boxes and it will compare it with the user's middle of the screen, and tell the user if they need to shift the camera up down left or right. However, in doing this, the coordinate system seems completely messed up, with some values throwing back -inf. Help? I'm not sure what's happening or what I can do to solve this problem, and add this function within the code.

You're more likely to get an answer posting this kind of question on a site like Stakoverflow.