pytelpoint: An Open-Source Package for Modeling and Assessing Telescope Pointing Performance

This paper presents pytelpoint, an open-source Python s package that uses PyMC2 (https://www.pymc . io/) to perform robust analysis of telescope pointing performance. It implements pointing models in a way similar to TPOINT3 and uses compatible parameter names and definitions. This way results can be easily compared with previous TPOINT analysis and implemented in telescope control systems that use TPOINT or TPOINT-compatible pointing models. The Bayesian modeling techniques that PyMC enables allow for much more robust determinations of the uncertainties in model parameters and the correlations between them. Several visualization routines are provided to help assess results and the residuals of the model fits. Some examples will be shown of how this has been used at the MMTO.(4) The initial release only supports elevation-azimuth telescopes. Support for other kinds of mounts is planned.