Matplotlib article – the real spirit of the open source software, free for all

http://nitace.bsd.uchicago.edu/misc/c3sci.pdf

The website is http://matplotlib.sourceforge.net/

And another one about iPython – an interactive shell

http://amath.colorado.edu/faculty/fperez/preprints/ipython-cise-final.pdf

and one more: NumPy/SciPy

http://www.computer.org/portal/cms_docs_cise/cise/2007/n3/10-20.pdf

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