line-racer 1.3.0

High resolution opacity calculation tool

line racer: An easy-to-use Python package for calculating (high-resolution) opacities from molecular line lists for atmospheric modeling

Welcome to the line racer repository! line racer is a Python package designed to compute high-resolution opacities from molecular (and in the future atomic) line lists. It combines two methods to calculate the line profiles: A direct calculation method using the Humlicek algorithm (Humlícek, 1982) and a speedup for calculating the line wings based on Mollière et al. (2015) to calculate the lines with the most intensity. A sampling technique of the line profiles based on Min (2017) for an ultra fast calculation of the lower intensity lines. The opacities can directly be output in the pRT format used by the petitRADTRANS code (Mollière et al., 2019, Blain et al., 2024), but also in other atmospheric modeling and retrieval codes.

Documentation

The code documentation, installation guide, and tutorial can be found here.

Attribution

If you use line racer in your work, please cite the following article: (still in preparation, DOI will be added here later).

License

Copyright 2025-2026 David Hägele and Paul Mollière

line racer is available under the MIT license. See the LICENSE file for more information.