systole.hrv.recurrence_matrix

systole.hrv.recurrence_matrix(rr: ndarray, m: int = 10, tau: int = 1) → ndarray

Compute the recurrence matrix from an array of RR intervals [1].

Parameters

rr

R-R interval time-series. Can be in seconds or miliseconds.

m

The embedding dimension. This corresponds to the length of the subsamples. Defaults to 10.

tau

The embedding lag. This corresponds to the number of datapoints that are skipped when creating the sub-sample. Defaults to 1 (take all values).

Returns

rc

The recurrence matrix.

References

1

H. Dabire, D. Mestivier, J. Jarnet, M.E. Safar, and N. Phong Chau. Quantification of sympathetic and parasympathetic tones by nonlinear indexes in normotensive rats. amj, 44:H1290–H1297, 1998.