emcee v3: A Python ensemble sampling toolkit for affine-invariant MCMC

Understand

emcee is a Python library implementing a class of affine-invariant ensemble samplers for Markov chain Monte Carlo (MCMC).

• This package has been widely applied to probabilistic modeling problems in astrophysics where it was originally published, with some applications in other fields.
• When it was first released in 2012, the interface implemented in emcee was fundamentally different from the MCMC libraries that were popular at the time, such as PyMC, because it was specifically designed to work with "black box" models instead of structured graphical models.
• This has been a popular interface for applications in astrophysics because it is often non-trivial to implement realistic physics within the modeling frameworks required by other libraries.