By default installed packages are available from the Octave prompt,
but it is possible to control this using the pkg load and
pkg unload commands. The functions from a package can be
removed from the Octave path by typing
pkg unload package_name
where package_name is the name of the package to be removed
from the path.
In much the same way a package can be added to the Octave path by typing
pkg load package_name