This is the initial problem: using the Thomas Sanchez Lengeling Library - Kinect v2 for processing 0.7.6 - I realized that the getZ() didn't work (i.e the position in the z axis didn't print into the txt file)
I read over the forum of Thomas Sanchez Lengeling that he fixed bugs in a more recent version of Kinect v2 for processing. So I went onto processing then Sketch>Import Library>add Library>(searched for kinect)> then clicked update.
It gives me an Error, The installation failed. I can't go back to the previous version (Kinect v2 for processing 0.7.6). I tried every sort of reinstalling or rebooting, I'm pretty sure it is something to do with the fact that the update isn't finished or something like that.
Thank you for your help.