Lybniz is an easy to use mathematical function graph plotter using pyGTK.
The project was started by Thomas Führinger. It is now also worked on by Sam Tygier.
The latest stable release is 1.3.1
Lybniz 1.3.1 Release notes./lybniz.pyin the directory you downloaded it to.
./setup.py install
Daniel Martín Yerga has ported Lybniz 1.3 to the maemo platform. Packages are a available from the Maemo Garage.
Lybniz development happens at Source Forge.
Have a look a the hackers guide.
Bug reports can be filed at Lybniz bug tracker, or sent by email to samtygier at yahoo dot co dot uk.
Since version 1.1, lybniz has used safe evaluation of expressions. This is explained here, Using eval() safely in Python.