Download _dot_pdrc into your home folder
and rename it to
.pdrc

Open .pdrc in an editor and make the following changes...
Make sure the paths in .pdrc are the right ones for where you put netpd.
A nice place is in your home directory in subfolder pd, subfolder netpd

Note:
You will not see .pdrc in your folder listing with Linux 'ls' command
because its name begins with dot
unless you use the '-a' qualifier, ie type
ls -a