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arXiv · 2409.08090

nifty-ls: Fast and Accurate Lomb-Scargle Periodograms Using a Non-Uniform FFT

Lehman H. Garrison·Dan Foreman-Mackey·Yu-hsuan Shih·Alex Barnett
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Abstract

We present nifty-ls, a software package for fast and accurate evaluation of the Lomb-Scargle periodogram. nifty-ls leverages the fact that Lomb-Scargle can be computed using a non-uniform FFT (NUFFT), which we evaluate with the Flatiron Institute NUFFT package (finufft). This approach achieves a many-fold speedup over the Press & Rybicki (1989) method as implemented in Astropy and is simultaneously many orders of magnitude more accurate. nifty-ls also supports fast evaluation on GPUs via CUDA and integrates with the Astropy Lomb-Scargle interface. nifty-ls is publicly available as open-source software.

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Lehman H. Garrison, Dan Foreman-Mackey, Yu-hsuan Shih, Alex Barnett. 2024-09-12. nifty-ls: Fast and Accurate Lomb-Scargle Periodograms Using a Non-Uniform FFT. https://arxiv.org/abs/2409.08090

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