Topaz is a graph plotting system for scientists and engineers.

1. Topaz has a powerful graph expression and functions such as least square
   method.  Topaz provides almost all functions that you need to make
   a 2D scattering graph.

2. Topaz has a polished character based user interface.

3. Topaz has powerful macro language of "Topaz script", which is like
   Perl.  You can expand topaz itself or you can perform batch jobs using
   topaz scripts.

Topaz official Web Page.

WWW: http://hp.vector.co.jp/authors/VA007663/topaz/