The following are my notes and completed examples for the Coursera Machine Learning class
The instructions I found on the web appeared to be out of date, and were a bit more complicated than required. I use Homebrew on my Mac, and unfortunately, there are two versions of Octave available for installation, one through regular brew (brew install octave) and a cask version (brew cask install octave).
ADVICE: Do not use the Homebrew cask version of Octave. It'll probably work, but it's outdated. Instead, just use the following commmand, which should get you up and running. I already have Java installed, hence the --without-java option.
brew install octave --without-java --with-gui --with-qt