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

TL;DR

nifty-ls is a software package that significantly accelerates and improves the accuracy of Lomb-Scargle periodogram computations by utilizing non-uniform FFTs, supporting GPU acceleration and integration with existing astronomy tools.

Contribution

The paper introduces nifty-ls, a novel software that uses NUFFT for fast, accurate Lomb-Scargle periodogram evaluation, outperforming previous methods in speed and precision.

Findings

Achieves many-fold speedup over traditional methods

Provides orders of magnitude higher accuracy

Supports GPU acceleration via CUDA

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.