> You would use Octave/ Matlab instead of Julia, R or Python because Matlab syntax is the cleanest and most succinct way currently to articulate complex (in both senses) matrix algorithms...I am pretty sure you need fewer characters or LOC to say the same thing in Matlab than in the other scientific languages mentioned.

Julia syntax is mostly Matlab syntax with the parens-for-array-indexing replaced with square brackets. Its main shortcoming WRT Matlab is that it's a new language and a lot of things still need to be implemented, but the built-in linalg support is pretty good.

Python is also not that bad with pylab, which eliminates most of the verbosity of calling numpy/scipy functions directly, although it might still end up being more LOC than Matlab in some cases. I have only minimal experience with R, so I can't comment there.