LARY\_CR is a software package dedicated to the study of cardiovascular and respiratory rhythms, developed in the SCILAB\_SCICOS scientific environment. It presents signal processing methods, from events detection on raw signals to the variability analysis of the resulting time series. The events detection concerns the heart beat recognition on the electrocardio- gram, defining the RR time series, the maxima and minima on the arterial blood pressure defining the systolic and diastolic time series. These detections are followed by the resampling of the time series then their analyse. This analyse uses temporal and time frequency methods: Fourier Transform, spectral gain between the cardiac and blood pressure series, Smooth Pseudo Wigner\_Ville Distribution, Complex DeModulation, temporal method of the cardiovascular Sequences. This software is aiming to give some tools for studying the autonomic nervous system, acting in particular in the baroreflex loop; its functionnin- g is reflected by the cardiovascular variabilities and their relationships with the other physiological signals, especially the respiratory activity.