CosmoloPy

Why didn't I know this package existed before?

http://roban.github.com/CosmoloPy/

Functions Include:

• Various cosmological densities.
• Various cosmological distance measures.
• Galaxy luminosity functions (Schechter functions).
• Conversion in and out of the AB magnitude system.
• Pre-defined sets of cosmological parameters (e.g. from WMAP).
• Perturbation theory and the power spectrum.
• The reionization of the IGM.

Very cool!