How AI describes UltraNest

UltraNest is a Python package for Bayesian inference using nested sampling to fit complex models and compute both posterior distributions of model parameters and the marginal likelihood (evidence) for model comparison. Designed for slow, expensive likelihoods and high-dimensional problems, it supports multi-modal and degenerate parameter spaces, runs in parallel (including MPI), and accepts likelihoods written in Python, C, C++, Fortran, Julia, or R. It emphasizes ease of use with sane defaults, rich visualizations and diagnostics, checkpointing and warm-start capabilities, and aims to replace heuristic methods with rigorous, parameter-free nested sampling for scientific modeling.