12.2.7. obspy.signal.trigger.ar_pick¶

ar_pick(a, b, c, samp_rate, f1, f2, lta_p, sta_p, lta_s, sta_s, m_p, m_s, l_p, l_s, s_pick=True)[source]¶

Pick P and S arrivals with an AR-AIC + STA/LTA algorithm.

The algorithm picks onset times using an Auto Regression - Akaike Information Criterion (AR-AIC) method. The detection intervals are successively narrowed down with the help of STA/LTA ratios as well as STA-LTA difference calculations. For details, please see [Akazawa2004].

An important feature of this algorithm is that it requires comparatively little tweaking and site-specific settings and is thus applicable to large, diverse data sets.

Parameters:	a (numpy.ndarray) Z signal the data. b (numpy.ndarray) N signal of the data. c (numpy.ndarray) E signal of the data. samp_rate (float) Number of samples per second. f1 (float) Frequency of the lower bandpass window. f2 (float) Frequency of the upper .andpass window. lta_p (float) Length of LTA for the P arrival in seconds. sta_p (float) Length of STA for the P arrival in seconds. lta_s (float) Length of LTA for the S arrival in seconds. sta_s (float) Length of STA for the S arrival in seconds. m_p (int) Number of AR coefficients for the P arrival. m_s (int) Number of AR coefficients for the S arrival. l_p (float) Length of variance window for the P arrival in seconds. l_s (float) Length of variance window for the S arrival in seconds. s_pick (bool) If True, also pick the S phase, otherwise only the P phase.
Return type:	tuple
Returns:	A tuple with the P and the S arrival.