class Amplitude(force_resource_id=True, *args, **kwargs)[source]

Bases: obspy.core.event.base.__Amplitude

This class represents a quantification of the waveform anomaly, usually a single amplitude measurement or a measurement of the visible signal duration for duration magnitudes.

  • resource_id (ResourceIdentifier) Resource identifier of Amplitude.
  • force_resource_id (bool, optional) If set to False, the automatic initialization of resource_id attribute in case it is not specified will be skipped.
  • generic_amplitude (float) Measured amplitude value for the given waveformID. Note that this attribute can describe different physical quantities, depending on the type and category of the amplitude. These can be, e.g., displacement, velocity, or a period. If the only amplitude information is a period, it has to specified here, not in the period attribute. The latter can be used if the amplitude measurement contains information on, e.g., displacement and an additional period. Since the physical quantity described by this attribute is not fixed, the unit of measurement cannot be defined in advance. However, the quantity has to be specified in SI base units. The enumeration given in attribute unit provides the most likely units that could be needed here. For clarity, using the optional unit attribute is highly encouraged.
  • generic_amplitude_errors (QuantityError) AttribDict containing error quantities.
  • type (str, optional)

    Describes the type of amplitude using the nomenclature from Storchak et al. (2003). Possible values are:

    • unspecified amplitude reading ('A'),
    • amplitude reading for local magnitude ('AML'),
    • amplitude reading for body wave magnitude ('AMB'),
    • amplitude reading for surface wave magnitude ('AMS'), and
    • time of visible end of record for duration magnitude ('END').
  • category (str, optional) Amplitude category. This attribute describes the way the waveform trace is evaluated to derive an amplitude value. This can be just reading a single value for a given point in time (point), taking a mean value over a time interval (mean), integrating the trace over a time interval (integral), specifying just a time interval (duration), or evaluating a period (period). See AmplitudeCategory for allowed values.
  • unit (str, optional) Amplitude unit. This attribute provides the most likely measurement units for the physical quantity described in the genericAmplitude attribute. Possible values are specified as combinations of SI base units. See AmplitudeUnit for allowed values.
  • method_id (ResourceIdentifier, optional) Describes the method of amplitude determination.
  • period (float, optional) Dominant period in the timeWindow in case of amplitude measurements. Not used for duration magnitude. Unit: s
  • snr (float, optional) Signal-to-noise ratio of the spectrogram at the location the amplitude was measured.
  • time_window (TimeWindow, optional) Description of the time window used for amplitude measurement. Recommended for duration magnitudes.
  • pick_id (ResourceIdentifier, optional) Refers to the resource_id of an associated Pick object.
  • waveform_id (ResourceIdentifier, optional) Identifies the waveform stream on which the amplitude was measured.
  • filter_id (ResourceIdentifier, optional) Identifies the filter or filter setup used for filtering the waveform stream referenced by waveform_id.
  • scaling_time (UTCDateTime, optional) Scaling time for amplitude measurement.
  • scaling_time_errors (QuantityError) AttribDict containing error quantities.
  • magnitude_hint (str, optional)

    Type of magnitude the amplitude measurement is used for. This is a free-text field because it is impossible to cover all existing magnitude type designations with an enumeration. Possible values are:

    • unspecified magnitude ('M'),
    • local magnitude ('ML'),
    • body wave magnitude ('Mb'),
    • surface wave magnitude ('MS'),
    • moment magnitude ('Mw'),
    • duration magnitude ('Md')
    • coda magnitude ('Mc')
    • 'MH', 'Mwp', 'M50', 'M100', etc.
  • evaluation_mode (str, optional) Evaluation mode of Amplitude. See EvaluationMode for allowed values.
  • evaluation_status (str, optional) Evaluation status of Amplitude. See EvaluationStatus for allowed values.
  • comments (list of Comment, optional) Additional comments.
  • creation_info (CreationInfo, optional) CreationInfo for the Amplitude object.


For handling additional information not covered by the QuakeML standard and how to output it to QuakeML see the ObsPy Tutorial.


__abstractmethods__ frozenset() -> empty frozenset object
__doc__ str(object=’‘) -> str
__module__ str(object=’‘) -> str
__slots__ tuple() -> empty tuple
__weakref__ list of weak references to the object (if defined)
defaults dict() -> new empty dictionary
do_not_warn_on list() -> new empty list
item tuple() -> empty tuple
key str(object=’‘) -> str
readonly list() -> new empty list
warn_on_non_default_key bool(x) -> bool

Public Methods

pop If key is not found, d is returned if given, otherwise KeyError is raised.
popitem as a 2-tuple; but raise KeyError if D is empty.

Private Methods


Private methods are mainly for internal/developer use and their API might change without notice.

_pretty_str Return better readable string representation of AttribDict object.

Special Methods

__dir__ default dir() implementation
__eq__ Two instances are considered equal if all attributes and all lists
__format__ default object formatter
__getattr__ Py3k hasattr() expects an AttributeError no KeyError to be
__new__ Create and return a new object.
__reduce__ helper for pickle
__reduce_ex__ helper for pickle
__setattr__ Custom property implementation that works if the class is
__sizeof__ size of object in memory, in bytes
__str__ Fairly extensive in an attempt to cover several use cases.