ColdPress: Efficient Quantile-Based Compression of Photometric Redshift PDFs
Abstract
ColdPress is a Python module that compresses photometric redshift probability distribution functions (PDFs) by encoding quantiles of their cumulative distribution. For a fixed packet size (the default is 80 bytes per PDF), ColdPress attains a reconstruction accuracy comparable to the sparse-basis representation method implemented in the pdf_storage module of Carrasco-Kind & Brunner (2014), yet reduces the computational cost by a factor of ~7000. I describe the implementation and quantify its compression speed and reconstruction accuracy in comparison to pdf_storage for real-life PDFs from two different photometric redshift codes. ColdPress is free software, available at https://github.com/ahc-photoz/coldpress-project.
Cite
@article{arxiv.2507.12481,
title = {ColdPress: Efficient Quantile-Based Compression of Photometric Redshift PDFs},
author = {Antonio Hernán-Caballero},
journal= {arXiv preprint arXiv:2507.12481},
year = {2025}
}
Comments
Published in Research Notes of the American Astronomical Society. 3 pages, 1 figure. Code available at https://github.com/ahc-photoz/coldpress-project