Installation fails due to lack of numpy
I have a case where I wrote a requirements file to install pandas. Included in the requirements file is an entry to install numpy alongside. The installation fails because pandas is trying to do an import (in its setup.py) of numpy which isn't installed yet.

Due to the fact that either setuptools or distribute is used for the installation of pandas, I think it's safe to trust that setuptools/distribute will ensure that the necessary version of numpy exists before installing pandas.
