matplotlib is a python 2D plotting library which produces publication quality figures in a variety of hardcopy formats and interactive environments across platforms. matplotlib can be used in python scripts, the python and ipython shell (ala matlab or mathematica), web application servers, and various graphical user interface toolkits.
For installation instructions and requirements, see the INSTALL file.
After installation, you can launch the test suite:
python setup.py test
Or from the python interpreter:
import matplotlib matplotlib.test()
Consider reading http://matplotlib.org/devel/coding_guide.html#testing for more information.