D H said:
Octave is nothing like Mathematica. You are perhaps thinking of Matlab, which is what octave is attempting to replicate.
Yes - GNU-Octave is designed to be a free-software replacement for Matlab and a core for other programs with the same aim but perhaps more gui-oriented and with prettier output.
Did not mean to appear to claim that it was anything else.
The similarities and differences have been the subject of
another thread.
And here is a
comparison between octave and maxima. On a reveiw of 20 sites, it seems typical of the observations, though some posts in the physicsforums thread (prev link) extend the typical observations.
Octave and Sage come up a lot in other forum responses to the same question with sage being touted as most similar to mathematica. When someone is most used to one, they are best to look for the most similar, appropriately licensed, replacement that otherwise suits their needs.
Maxima uses DOE-MACSIMA
GNU-Octave uses GiNaC and CLN for symbolic computing.
Perhaps it would be helpful to know where Maxima fails the OP before making any firm recommendations. Meantime - found a review comparing the three names that keep coming up:
Octave - Spyder - Maxima ... also a description of how SAGE relates to these three.
Should be a place to start anyway.
Enjoy.