PSI ("Personal Statistics and Inference" or "Python Statistical Interpreter") is
intended to be a proyect for having a tool allowing easy data input and
visualization, as well as a basic framework to implement new statistical or
numerical calculations and graphical representations through a simple API (not
yet available). It runs a GUI made with wxPython and makes calculations using
NumPy/SciPy, and plotting functions use Matplotlib, so make sure you have these
packages installed before launching PSI.

Its main purpose is getting ride of commercial statistical software. If you need
really beautiful, professional-looking graphs and charts, take a look at SOFA
(Statistics Open For All, http://www.sofastatistics.com), an impressive piece
of software which happens to be also written in Python, BTW.