Earlier quoted context omitted.
As someone who loves Matlab but would rather use a free-software solution, I must say that Octave is not an effective replacement for Matlab. Matlab itself is just so much more feature-complete and polished, turning to Octave feels like going back two decades in technology.
In what way is Matlab more feature-complete and polished? With respect to just the actual language Octave is nearly a 1:1 implementation of Matlab, which is an primary goal to stride for and maintain, any differences between the two is considered a bug even.
I don't see a compelling reason to use Octave unless you're trying to avoid paying for a Matlab license. If you're going to switch tools, why not switch to NumPy/SciPy and get the advantage of using a full-featured programming language?