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Some of the options you have under OSX are, in my personal order of preference:
- Install macports. Then install matplotlib sudo port install py27-matplotlib.
- Install homebrew. Then install python, then matplotlib using pip pip install matplotlib.
- Get the enthought python distribution (now called Canopy).
- Get the continuum distribution.
You probably don't want to use the python version that comes preinstalled with OSX. Using one of the other options keeps your python environment separate from your system environment and you'll have a more recent python version.
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