fqlag is a python library to characterize the variability in the frequency domain of light curves that are not continuously sampled. This supersedes the plag library, with a different implementation that is more stable during the calculations.
Both libraries implement the method presented in Zoghbi et. al. (2013) paper (Astrophysical Journal; 2013. 777. 24) to calculate periodogram and time/phase lags in the frequency domain from unevenly-sampled light curves.
- pip install fqlag
- OR Download and add the directory
fqlag/flagto PYTHONPATH or put it somewhere where python can find it.
- Check out the Getting Started notebook, which can be browsed here.
- There are additional example in the
tutorials/test.pyfile.
Please cite the following paper when using the code.
@ARTICLE{2013ApJ...777...24Z,
author = {Zoghbi, A. and Reynolds, C. and Cackett, E.~M.},
title = "{Calculating Time Lags from Unevenly Sampled Light Curves}",
journal = {\apj},
keywords = {black hole physics, galaxies: active, galaxies: nuclei, methods: data analysis, Astrophysics - High Energy Astrophysical Phenomena},
year = 2013,
month = nov,
volume = {777},
number = {1},
eid = {24},
pages = {24},
doi = {10.1088/0004-637X/777/1/24},
archivePrefix = {arXiv},
eprint = {1308.5852},
primaryClass = {astro-ph.HE},
adsurl = {https://ui.adsabs.harvard.edu/abs/2013ApJ...777...24Z},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}