periodogram

elk.stats.periodogram(time, flux, flux_err, frequencies, n_bootstrap=100, max_peaks=25, freq_thresh=5)

Generate a bootstrapped Lomb-Scargle periodogram and various associated statistics

Parameters

timendarray

Times of observations

fluxndarray

Flux for each observations

flux_errndarray

Errors on the fluxes

frequenciesndarray

Frequencies at which to evaluate the periodogram

n_bootstrapint, optional

How many bootstraps to perform, by default 100

max_peaksint, optional

Fixed number of max peaks to return, by default 25. If None is given then the number of peaks that exist will be returned rather than truncated/padded to this fixed number.

freq_threshint, optional

Threshold for high vs. low frequency, by default 5 days since this represents a threshold of how different stars vary McQuillan+2012.

Returns

medndarray

Median power at each frequency

percentilesndarray

1 and 2-sigma power at each frequency (in order of 2-, 1-, 1+, 2+) with shape (4, len(frequencies))

lsp_statsdict

Dictionary of various statistics related to the periodogram. Keys are: [“max_power”, “freq_at_max_power”, “peak_freqs”, “power_at_peaks”, “n_peaks”, “ratio_of_power_at_high_v_low_freq”]. Many of these are self explanatory but we note that peak_freqs and power_at_peaks will always have a length of max_peaks may need to be masked to just take the first n_peaks. (This feature is useful when saving to a FITS file with a required fixed column width).