glg(series, tmin=None, tmax=None, fill_method='nearest', limit=0, output='mean', min_n_meas=16, min_n_years=8, year_offset='a-mar')[source]#

Calculate the ‘Gemiddelde Laagste Grondwaterstand’ (Average Low GW Level).

  • series (pandas.Series with a DatetimeIndex) – The pandas Series of which the statistic is determined.

  • tmin (pandas.Timestamp, optional) – The lowest index to take into account.

  • tmax (pandas.Timestamp, optional) – The highest index to take into account.

  • fill_method (str, optional) – see .. :mod: pastas.stats.__gxg__

  • limit (int or None, optional) – Maximum number of days to fill using fill method, use None to fill nothing.

  • output (str, optional) – output type * ‘mean’ (default) : for mean of yearly values. * ‘yearly’: for series of yearly values. * ‘g3’: for series with selected data for calculating statistic. * ‘semimonthly’: for series with all data points (14th, 28th of each month).

  • min_n_meas (int, optional) – Minimum number of measurements per year (at maximum 24).

  • min_n_years (int, optional) – Minimum number of years.

  • year_offset (resampling offset. Use 'a' for calendar years) – (jan 1 to dec 31) and ‘a-mar’ for hydrological years (apr 1 to mar 31).


Series of yearly values or mean of yearly values.

Return type

pd.Series or scalar


Classic method resampling the series to every 14th and 28th of the month. Taking the mean of the mean of three lowest values per year.