def lightcurve_moments(ftimes, fmags, ferrs):
'''This calculates the weighted mean, stdev, median, MAD, percentiles, skew,
kurtosis, fraction of LC beyond 1-stdev, and IQR.
Parameters
----------
ftimes,fmags,ferrs : np.array
The input mag/flux time-series with all non-finite elements removed.
Returns
-------
dict
A dict with all of the light curve moments calculated.
'''
ndet = len(fmags)
if ndet > 9:
# now calculate the various things we need
series_median = npmedian(fmags)
series_wmean = (npsum(fmags * (1.0 / (ferrs * ferrs))) /
npsum(1.0 / (ferrs * ferrs)))
series_mad = npmedian(npabs(fmags - series_median))
series_stdev = 1.483 * series_mad
series_skew = spskew(fmags)
series_kurtosis = spkurtosis(fmags)
# get the beyond1std fraction
series_above1std = len(fmags[fmags > (series_median + series_stdev)])
series_below1std = len(fmags[fmags < (series_median - series_stdev)])
# this is the fraction beyond 1 stdev
series_beyond1std = (series_above1std + series_below1std) / float(ndet)
# get the magnitude percentiles
series_mag_percentiles = nppercentile(
fmags, [5.0, 10, 17.5, 25, 32.5, 40, 60, 67.5, 75, 82.5, 90, 95])
return {
'median': series_median,
'wmean': series_wmean,
'mad': series_mad,
'stdev': series_stdev,
'skew': series_skew,
'kurtosis': series_kurtosis,
'beyond1std': series_beyond1std,
'mag_percentiles': series_mag_percentiles,
'mag_iqr': series_mag_percentiles[8] - series_mag_percentiles[3],
}
else:
LOGERROR('not enough detections in this magseries '
'to calculate light curve moments')
return None
def lightcurve_flux_measures(ftimes, fmags, ferrs, magsarefluxes=False):
'''This calculates percentiles and percentile ratios of the flux.
Parameters
----------
ftimes,fmags,ferrs : np.array
The input mag/flux time-series with all non-finite elements removed.
magsarefluxes : bool
If the `fmags` array actually contains fluxes, will not convert `mags`
to fluxes before calculating the percentiles.
Returns
-------
dict
A dict with all of the light curve flux percentiles and percentile
ratios calculated.
'''
ndet = len(fmags)
if ndet > 9:
# get the fluxes
if magsarefluxes:
series_fluxes = fmags
else:
series_fluxes = 10.0**(-0.4 * fmags)
series_flux_median = npmedian(series_fluxes)
# get the percent_amplitude for the fluxes
series_flux_percent_amplitude = (npmax(npabs(series_fluxes)) /
series_flux_median)
# get the flux percentiles
series_flux_percentiles = nppercentile(
series_fluxes,
[5.0, 10, 17.5, 25, 32.5, 40, 60, 67.5, 75, 82.5, 90, 95])
series_frat_595 = (series_flux_percentiles[-1] -
series_flux_percentiles[0])
series_frat_1090 = (series_flux_percentiles[-2] -
series_flux_percentiles[1])
series_frat_175825 = (series_flux_percentiles[-3] -
series_flux_percentiles[2])
series_frat_2575 = (series_flux_percentiles[-4] -
series_flux_percentiles[3])
series_frat_325675 = (series_flux_percentiles[-5] -
series_flux_percentiles[4])
series_frat_4060 = (series_flux_percentiles[-6] -
series_flux_percentiles[5])
# calculate the flux percentile ratios
series_flux_percentile_ratio_mid20 = series_frat_4060 / series_frat_595
series_flux_percentile_ratio_mid35 = series_frat_325675 / series_frat_595
series_flux_percentile_ratio_mid50 = series_frat_2575 / series_frat_595
series_flux_percentile_ratio_mid65 = series_frat_175825 / series_frat_595
series_flux_percentile_ratio_mid80 = series_frat_1090 / series_frat_595
# calculate the ratio of F595/median flux
series_percent_difference_flux_percentile = (series_frat_595 /
series_flux_median)
series_percentile_magdiff = -2.5 * nplog10(
series_percent_difference_flux_percentile)
return {
'flux_median': series_flux_median,
'flux_percent_amplitude': series_flux_percent_amplitude,
'flux_percentiles': series_flux_percentiles,
'flux_percentile_ratio_mid20': series_flux_percentile_ratio_mid20,
'flux_percentile_ratio_mid35': series_flux_percentile_ratio_mid35,
'flux_percentile_ratio_mid50': series_flux_percentile_ratio_mid50,
'flux_percentile_ratio_mid65': series_flux_percentile_ratio_mid65,
'flux_percentile_ratio_mid80': series_flux_percentile_ratio_mid80,
'percent_difference_flux_percentile': series_percentile_magdiff,
}
else:
LOGERROR('not enough detections in this magseries '
'to calculate flux measures')
return None
def lightcurve_flux_measures(ftimes, fmags, ferrs, magsarefluxes=False):
'''
This calculates percentiles of the flux.
'''
ndet = len(fmags)
if ndet > 9:
# get the fluxes
if magsarefluxes:
series_fluxes = fmags
else:
series_fluxes = 10.0**(-0.4 * fmags)
series_flux_median = npmedian(series_fluxes)
# get the percent_amplitude for the fluxes
series_flux_percent_amplitude = (npmax(npabs(series_fluxes)) /
series_flux_median)
# get the flux percentiles
series_flux_percentiles = nppercentile(
series_fluxes,
[5.0, 10, 17.5, 25, 32.5, 40, 60, 67.5, 75, 82.5, 90, 95])
series_frat_595 = (series_flux_percentiles[-1] -
series_flux_percentiles[0])
series_frat_1090 = (series_flux_percentiles[-2] -
series_flux_percentiles[1])
series_frat_175825 = (series_flux_percentiles[-3] -
series_flux_percentiles[2])
series_frat_2575 = (series_flux_percentiles[-4] -
series_flux_percentiles[3])
series_frat_325675 = (series_flux_percentiles[-5] -
series_flux_percentiles[4])
series_frat_4060 = (series_flux_percentiles[-6] -
series_flux_percentiles[5])
# calculate the flux percentile ratios
series_flux_percentile_ratio_mid20 = series_frat_4060 / series_frat_595
series_flux_percentile_ratio_mid35 = series_frat_325675 / series_frat_595
series_flux_percentile_ratio_mid50 = series_frat_2575 / series_frat_595
series_flux_percentile_ratio_mid65 = series_frat_175825 / series_frat_595
series_flux_percentile_ratio_mid80 = series_frat_1090 / series_frat_595
# calculate the ratio of F595/median flux
series_percent_difference_flux_percentile = (series_frat_595 /
series_flux_median)
series_percentile_magdiff = -2.5 * nplog10(
series_percent_difference_flux_percentile)
return {
'flux_median': series_flux_median,
'flux_percent_amplitude': series_flux_percent_amplitude,
'flux_percentiles': series_flux_percentiles,
'flux_percentile_ratio_mid20': series_flux_percentile_ratio_mid20,
'flux_percentile_ratio_mid35': series_flux_percentile_ratio_mid35,
'flux_percentile_ratio_mid50': series_flux_percentile_ratio_mid50,
'flux_percentile_ratio_mid65': series_flux_percentile_ratio_mid65,
'flux_percentile_ratio_mid80': series_flux_percentile_ratio_mid80,
'percent_difference_flux_percentile': series_percentile_magdiff,
}
else:
LOGERROR('not enough detections in this magseries '
'to calculate flux measures')
return None