Although processing of commutative expressions is built into Mathematica, relatively no support is given to noncommutative expression manipulation. These packages have been developed to fill this void. Commands for noncommuting algebra that are analogous to Mathematica commands are implemented, as well as others. The development of these packages has been directed by needs that arose from research in Control Theory Systems Theory and in Operator Theory. Also attached to the NCAlgebra package are files SYS* for doing calculations with engineering systems that are common in Hinfinity control and in differential games.
The latest version of NCAlgebra is available by anonymous ftp from osiris.ucsd.edu. NCAlgebra documentation in TeX .dvi form can be obtained from the ftp site.