pastas.stats.signatures#

This module contains methods to compute the groundwater signatures.

Functions

amplitude_range

Range of unscaled groundwater head.

autocorr

Lag where the first peak in the autocorrelation function occurs after Wang et al. (2006).

avg_seasonal_fluctuation

Classification according to Martens et al. (2013).

baseflow_index

Baseflow index according to Organization (2008).

baseflow_stability

Baseflow stability after Heudorfer et al. (2019).

bimodality_coefficient

Bimodality coefficient after Ellison (1987).

colwell_components

Colwell's predictability, constant, and contingency Colwell (1974).

colwell_constancy

Colwells constancy index after Colwell (1974).

colwell_contingency

Colwell's contingency Colwell (1974)

critical_bandwidth

Test statistic of the Silverman test, after Silverman (1981).

cv_date_min

Coefficient of variation of the date of annual minimum head.

cv_fall_rate

Coefficient of Variation in fall rate.

cv_period_mean

Coefficient of variation of mean head over a period (default monthly).

cv_rise_rate

Coefficient of Variation in rise rate.

duration_curve_range

Range of the duration curve between the percentile l and u after Richards (1990).

duration_curve_slope

Slope of the duration curve between percentile l and u after Oudin et al. (2010).

excess_mass

Test statistic of the dip test, after Hartigan and Hartigan (1985).

fall_rate

Mean negative head changes from one day to the next.

high_pulse_count

Number of times the series exceeds a certain threshold.

high_pulse_duration

Average duration of pulses where the head exceeds a certain threshold.

hurst_exponent

Hurst exponent according to Wang et al. (2006).

interannual_variation

Interannual variation after Martens et al. (2013).

low_pulse_count

Number of times the series drops below a certain threshold.

low_pulse_duration

Average duration of pulses where the head is below a certain threshold.

lyapunov_exponent

The exponential rate of divergence of nearby data points after Hilborn and others (2000).

magnitude

Difference of peak head to base head, divided by base head after Hannah et al. (2000).

mean_annual_maximum

Mean of annual maximum after Clausen and Biggs (2000).

parde_coefficients

Parde coefficients for each month Pardé (1933).

parde_seasonality

Parde seasonality according to Pardé (1933).

peak_base_time

Difference between peak and base head, standardized by duration of peak after Heudorfer et al. (2019).

peak_timescale

Area under peak divided by difference of peak head to peak base after Gaál et al. (2012).

recession_constant

Recession constant after Kirchner (2009).

recovery_constant

Recovery constant after Kirchner (2009).

reversals_avg

Average annual number of rises and falls in daily head.

reversals_cv

Coefficient of Variation in annual number of rises and falls.

richards_baker_index

Richards-Baker index according to Baker et al. (2004).

richards_pathlength

The path length of the time series, standardized by time series length after Baker et al. (2004).

rise_rate

Mean of positive head changes from one day to the next.

summary

Method to get many signatures for a time series.