obspy.clients.iris.client.Client.evalresp

Client.evalresp(network, station, location, channel, time=UTCDateTime(2024, 10, 15, 15, 10, 55, 587131), minfreq=1e-05, maxfreq=None, nfreq=200, units='def', width=800, height=600, annotate=True, output='plot', filename=None, **kwargs)[source]

Low-level interface for evalresp Web service of EarthScope (http://service.iris.edu/irisws/evalresp/) - release 1.0.0 (2011-08-11).

This method evaluates instrument response information stored at the EarthScope DMC and outputs ASCII data or Bode Plots.

Parameters:

  • network (str) – Network code, e.g. 'IU'.

  • station (str) – Station code, e.g. 'ANMO'.

  • location (str) – Location code, e.g. '00'. Use '--' for empty location codes.

  • channel (str) – Channel code, e.g. 'BHZ'.

  • time (UTCDateTime) – Evaluate the response at the given time. If not specified, the current time is used.

  • minfreq (float, optional) – The minimum frequency (Hz) at which response will be evaluated. Must be positive and less than the maxfreq value. Defaults to 0.00001 Hz (1/day ~ 0.000012 Hz).

  • maxfreq (float, optional) – The maximum frequency (Hz) at which response will be evaluated. Must be positive and greater than the minfreq value. Defaults to the channel sample-rate or the frequency of sensitivity, which ever is larger.

  • nfreq (int, optional) – Number frequencies at which response will be evaluated. Must be a positive integer no greater than 10000. The instrument response is evaluated on a equally spaced logarithmic scale. Defaults to 200.

  • units (str, optional) –

    Output Unit. Defaults to 'def'.

    'def'

    default units indicated in response metadata

    'dis'

    converts to units of displacement

    'vel'

    converts to units of velocity

    'acc'

    converts to units of acceleration

    If units are not specified, then the units will default to those indicated in the response metadata

  • width (int, optional) – The width of the generated plot. Defaults to 800. Can only be used with the output='plot', output='plot-amp' and output='plot-phase' options. Cannot be larger than 5000 and the product of width and height cannot be larger than 6,000,000.

  • height (int, optional) – The height of the generated plot. Defaults to 600. Can only be used with the output='plot', output='plot-amp' and output='plot-phase' options. Cannot be larger than 5000 and the product of width and height cannot be larger than 6,000,000.

  • annotate (bool, optional) –

    Can be either True or False. Defaults to True.

    • Draws vertical lines at the Nyquist frequency (one half the sample rate).

    • Draw a vertical line at the stage-zero frequency of sensitivity.

    • Draws a horizontal line at the stage-zero gain.

    Can only be used with the output='plot', output='plot-amp' and output='plot-phase' options.

  • output (str) –

    Output Options. Defaults to 'plot'.

    'fap'

    Three column ASCII (frequency, amplitude, phase)

    'cs'

    Three column ASCII (frequency, real, imaginary)

    'plot'

    Amplitude and phase plot

    'plot-amp'

    Amplitude only plot

    'plot-phase'

    Phase only plot

    Plots are stored to the file system if the parameter filename is set, otherwise it will try to use matplotlib to directly plot the returned image.

  • filename (str, optional) – Name of a output file. If this parameter is given nothing will be returned. Default is None.

Return type:

numpy.ndarray, str or None

Returns:

Returns either a NumPy ndarray, image string or nothing, depending on the output parameter.

Examples

  1. Returning frequency, amplitude, phase of first point.

    >>> from obspy.clients.iris import Client
>>> client = Client()
>>> dt = UTCDateTime("2005-01-01")
>>> data = client.evalresp("IU", "ANMO", "00", "BHZ", dt,
...                        output='fap')
>>> data[0]  # frequency, amplitude, phase of first point
array([  1.00000000e-05,   1.05593400e+04,   1.79200700e+02])

  2. Returning amplitude and phase plot.

    >>> from obspy.clients.iris import Client
>>> client = Client()
>>> dt = UTCDateTime("2005-01-01")
>>> client.evalresp("IU", "ANMO", "00", "BHZ", dt)

    (Source code)