Gentoo Packages

The VISA packages have been removed from the science overlay and are now available in the natinst overlay which also maintains the packages from National Instruments:

 https://github.com/AndrewAmmerlaan/natinst

The following packages have been moved

dev-perl/Lab-VISA
dev-python/PyVISA
dev-python/PyVISA-py
sci-libs/ni-visa

The octave-forge packages were removed from the science overlay.
You will need to use app-portage/g-octave to install the equivalent
packages to octave-forge using your Gentoo package manager.

g-octave project page: http://www.g-octave.org/
g-octave documentation: http://doc.g-octave.org/latest/