Using Octave over matlab is preferable for me for the same reasons many people use GIMP over photoshop. I use octave for things that are reasonably self-contain

Using Octave over matlab is preferable for me for the same reasons many people use GIMP over photoshop. I use octave for things that are reasonably self-contained, like the metaphorical editing of a single image. I like Python over octave for the kinds of uses that might cause someone to use python over GIMP for image processing, to extend the metaphor.