Best open source competitor to Matlab?
I know about octave, which seems to be pretty good, but there are a number of other programs and I am wondering if octave is best or not. I know that octave is designed to be compatible with Matlab (which will make things easier for me since I just spent three months working in Matlab for a summer job), but I don't know if it is the best overall system or not.
Is octave designed to be a complete copycat of Matlab or does it have its own functions/optimizations? It seems like if it is just a copy that would ultimately force it to be permanently inferior to Matlab, in much the same way that OpenOffice will never handle .docs as well as MS Word (while it would obviously have the advantage that octave code could be run in Matlab, but I don't care about that for my purposes).
I probably will use C++ for any really intensive work (although I may implement it in an interpreted high-level language first), but performance is definitely an important factor, as are debugging/plotting capabilities, and the features of the shell itself (e.g. matlab has a very nice shell, for example if you type in the first part of a command and use up, you cycle through only commands starting with that segment). Emacs integration is another big feature since I do basically all of this kind of work in emacs (even when using Matlab).
I am perfectly willing to learn a new system if I think it is better, so the fact that octave is a lot like Matlab isn't that big of a deal.
So out of all the open source alternatives then, is octave the best with regard to performance/debugging/shell features or are there better choices if I do not require Matlab compatibility?
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