Now compute FPHP of two files.
Code compiles and runs, but does not register very well. I am trying to register
capture0001.pcd and capture0004.pcd (which are not very close, but do have some overlap).

Perhaps I have an error or perhaps some parameters are not chosen appropriately.

I do not 100% understand how to plot and have the graphs stay plotted in the viewer. The graph
sometimes disappears or never appears.
.