Hi Dave: Thanks very much for the feedback. As I'm sure you know, feedback is invaluable. Can you "import gtk" interactively? (In the event you are not familiar with Python and Gtk, I should mention that it's a Python module, not Gtk+ the library. It's often referred to as PyGtk.) $ python Python 2.3.1 (#1, Sep 24 2003, 16:45:45) [GCC 3.2.3] on linux2 Type "help", "copyright", "credits" or "license" for more information. (ctl-D to exit) Please feel free to contact me offline with any response if you wish. Regards, Dave. P.S. Is anyone else having the "gtk import" problem? I invite anyone who has problems with these programs to contact me by personal email --- either desiring more information on how to use, coefficients already calculated, or whatever. I'll try to respond as soon as I can.