SWIFTGalaxy is a module that extends SWIFTSimIO tailored to analyses of particles belonging to individual simulated galaxies. It inherits from and extends the functionality of the SWIFTDataset. It understands the content of halo catalogues (supported: Velociraptor, Caesar, SOAP) and therefore which particles belong to a galaxy or other group of particles, and its integrated properties. The particles occupy a coordinate frame that is enforced to be consistent, such that particles loaded on-the-fly will match e.g. rotations and translations of particles already in memory. Intuitive masking of particle datasets is also enabled. Utilities to make working in cylindrical and spherical coordinate systems more convenient are also provided. Finally, tools to iterate efficiently over multiple galaxies are also provided.
Installation is as simple as pip install swiftgalaxy. numpy>=2.0 is required and will be installed automatically as a dependency.
If your use of SWIFTGalaxy leads to a publication, please cite the swiftgalaxy entry in the ASCL (indexed on ADS). Ideally specify the version used (Zenodo DOI, git commit ID and/or version number) and link to the github repository. A PyOpenSci review leading to a JOSS submission is in progress, please check back for updated citation information.
@MISC{
2025ascl.soft05002O,
author = {{Oman}, Kyle A.},
title = "{swiftgalaxy}",
keywords = {Software},
howpublished = {Astrophysics Source Code Library, record ascl:2505.002},
year = 2025,
month = may,
eid = {ascl:2505.002},
pages = {ascl:2505.002},
archivePrefix = {ascl},
eprint = {2505.002},
adsurl = {https://ui.adsabs.harvard.edu/abs/2025ascl.soft05002O},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}Please also consider the citations requested for SWIFTSimIO.
Code contributions are very welcome! A good place to start is the contributing guide and how to set up a development environment.
SWIFTGalaxy is licensed under GPL-3.0 and community members are expected to abide by the code of conduct.