This package by DavidBakhash provides multidimensional arrays simulated in EmacsLisp. Using it, you can do MatrixOperations, for example. Or you could use the AdvancedDeskCalculator.
Note that there is another file out there called multi.el, by BernardVauquelin?. That one does SearchAndReplace across multiple buffers.
Does anybody have cl-array.el (in the past located here http://mit.edu/cadet/www/cl-array.el) file, vers. 0.4? I cannot find it on the internet anymore :(
The last traces are here: http://calypso.tux.org/pipermail/xemacs-beta/2004-May/001503.html
It has been archived here: http://web.archive.org/web/20010617092325/http://mit.edu/cadet/www/cl-array.el
*Lisp:cl-array.el – cl-array.el circa 1999-06-02 it appears to have a GPLv2 or later license so adding a local copy