systole.hrv.nonlinear_domain#

systole.hrv.nonlinear_domain(rr: List | ndarray, input_type: str = 'rr_ms') → DataFrame[source]#

Extract the non-linear features of heart rate variability.

Parameters:

rr: R-R interval time-series, peaks or peaks index vectors. The default expected vector is R-R intervals in milliseconds. Other data format can be provided by specifying the “input_type” (can be “rr_s”, “peaks” or “peaks_idx”).
input_type: The type of input provided. Can be “peaks”, “peaks_idx”, “rr_ms” or “rr_s”. Defaults to “rr_ms”.

Returns:

stats: Nonlinear domain summary statistics. * ‘SD1’ : SD1, the standard deviation of the poincare plot orthogonal to the identity line (ms). * ‘SD2’ : SD2, the standard deviation of the poincare plot along the identity line (ms). * ‘recurrence_rate’ : The recurrence rate in the recurrence plot (%). * ‘l_max’ : The maximun diagonal length in the recurrence plot (beats). * ‘l_mean’ : The mean diagonal length in the recurrence plot (beats). * ‘determinism_rate’ : The determinism rate in the recurrence plot (%). * ‘shannon_entropy’ : The Shannon entropy.