Code for the logp is here, it’s highly unreadable I would say but touches on some things you may want to be aware: compute stuff on log-scale, try to use vectorization… pymc-extras/pymc_extras/model/marginal/distributions.py at 7d62c53139419df8f9d7ef89b69ec07befbbad4d · pymc-devs/pymc-extras · GitHub