compute_fvar#
- gammapy.stats.compute_fvar(flux, flux_err, axis=0)[source]#
Calculate the fractional excess variance.
This method accesses the
FLUX
andFLUX_ERR
columns from the lightcurve data.The fractional excess variance
, an intrinsic variability estimator, is given by:It is the excess variance after accounting for the measurement errors on the light curve
. is the variance.It is important to note that the errors on the flux must be gaussian.
- Parameters
- Returns
- fvar, fvar_err
ndarray
Fractional excess variance.
- fvar, fvar_err
References
- Vaughan2003
“On characterizing the variability properties of X-ray light curves from active galaxies”, Vaughan et al. (2003) https://ui.adsabs.harvard.edu/abs/2003MNRAS.345.1271V