obspy.signal.polarization.polarization_analysis

polarization_analysis(stream, win_len, win_frac, frqlow, frqhigh, stime, etime, verbose=False, method='pm', var_noise=0.0)[source]

Method carrying out polarization analysis with the [Flinn1965b], [Jurkevics1988], ParticleMotion, or [Vidale1986] algorithm.

Parameters
  • stream (Stream) – 3 component input data.

  • win_len (float) – Sliding window length in seconds.

  • win_frac (float) – Fraction of sliding window to use for step.

  • var_noise (float) – resembles a sphere of noise in PM where the 3C is excluded

  • frqlow (float) – lower frequency for PM

  • frqhigh (float) – higher frequency for PM

  • stime (obspy.core.utcdatetime.UTCDateTime) – Start time of interest

  • etime (obspy.core.utcdatetime.UTCDateTime) – End time of interest

  • method (str) – the method to use. one of "pm", "flinn" or "vidale".

Return type

dict

Returns

Dictionary with keys "timestamp" (POSIX timestamp, can be used to initialize UTCDateTime objects), "azimuth", "incidence" (incidence angle) and additional keys depending on used method: "azimuth_error" and "incidence_error" (for method "pm"), "rectilinearity" and "planarity" (for methods "flinn" and "vidale") and "ellipticity" (for method "flinn"). Under each key a ndarray is stored, giving the respective values corresponding to the "timestamp" ndarray.