"GNU Octave is a high-level language, primarily intended for numerical computations", according to its home page [L1 ]. Its language "is mostly compatible with Matlab." Additional compatibility functions are available at octave-forge[L2 ].
dead link:: http://merlin.inescn.pt/~qual/tk_octave/index.htm ?
Try http://www.gnu.org/software/octave/ or http://www.octave.org
Tkoctave
octcl: Tcl client for the Octave server. Part of octave-forge[L3 ].
Provocatively, the 2006 second edition of the popular Scientific Computing with MATLAB was retitled, Scientific Computing with MATLAB and Octave. Open source marches on.
Also, octaves are 8-dimensional numbers, just as complex numbers are 2-dimensional and quaternions 4-dimensional, and more dimensions seem not to make any sense anymore, in number theory.
AM I think you will find that octonions are 8-dimensional numbers, they are also called biquaternions.
Their properties or better the lack of familiar properties is rather curious:
(This latter lack of properties seems to be responsible for there not being a system of 16-dimensional numbers ...)
The existence of octonions does mean that in 7-dimensional space, just as in 3-dimensional space, but in no others, there exists an out-product for vectors.
(Okay, there are all rather impractical faits divers - but I thought you might like to know :)