  orbitize! is an open-source, object-oriented software package for fitting the
orbits of directly-imaged objects. It packages the Orbits for the Impatient
(OFTI) algorithm and a parallel-tempered Markov Chain Monte Carlo (MCMC)
algorithm into a consistent and intuitive Python API. orbitize! makes it easy
to run standard astrometric orbit fits; in less than 10 lines of code, users
can read in data, perform one fit using OFTI and another using MCMC, and make
two publication-ready figures. Extensive pedagogical tutorials, intended to be
navigable by both orbit-fitting novices and seasoned experts, are available on
our documentation page. We have designed the orbitize! API to be flexible and
easy to use/modify for unique cases. orbitize! was designed by members of the
exoplanet imaging community to be a central repository for algorithms,
techniques, and know-how developed by this community. We intend for it to
continue to expand and change as the field progresses and new techniques are
developed, and call for community involvement in this process. Complete and
up-to-date documentation is available at orbitize.info.
