squirrel.pile

class Pile(squirrel=None)

Bases: object

pyrocko.pile.Pile surrogate: waveform lookup, loading and caching.

This class emulates most of the older pyrocko.pile.Pile methods by using calls to a pyrocko.squirrel.base.Squirrel instance behind the scenes.

This interface can be used as a drop-in replacement for piles which are used in existing scripts and programs for efficient waveform data access. The Squirrel-based pile scales better for large datasets. Newer scripts should use Squirrel’s native methods to avoid the emulation overhead.

Note

Many methods in the original pile implementation lack documentation, as do here. Read the source, Luke!

chopper(tmin=None, tmax=None, tinc=None, tpad=0.0, group_selector=None, trace_selector=None, want_incomplete=True, degap=True, maxgap=5, maxlap=None, keep_current_files_open=False, accessor_id='default', snap=(<built-in function round>, <built-in function round>), include_last=False, load_data=True, style=None)

Get iterator for shifting window wise data extraction from waveform archive.

Parameters:

• tmin – start time (default uses start time of available data)
• tmax – end time (default uses end time of available data)
• tinc – time increment (window shift time) (default uses tmax-tmin)
• tpad – padding time appended on either side of the data windows (window overlap is 2*tpad)
• group_selector – ignored in squirrel-based pile
• trace_selector – filter callback taking pyrocko.trace.Trace objects
• want_incomplete – if set to False, gappy/incomplete traces are discarded from the results
• degap – whether to try to connect traces and to remove gaps and overlaps
• maxgap – maximum gap size in samples which is filled with interpolated samples when degap is True
• maxlap – maximum overlap size in samples which is removed when degap is True
• keep_current_files_open – whether to keep cached trace data in memory after the iterator has ended
• accessor_id – if given, used as a key to identify different points of extraction for the decision of when to release cached trace data (should be used when data is alternately extracted from more than one region / selection)
• snap – replaces Python’s round() function which is used to determine indices where to start and end the trace data array
• include_last – whether to include last sample
• load_data – whether to load the waveform data. If set to False, traces with no data samples, but with correct meta-information are returned
• style – set to 'batch' to yield waveforms and information

about the chopper state as pyrocko.pile.Batch objects. By default lists of pyrocko.trace.Trace objects are yielded. :returns: iterator providing extracted waveforms for each extracted

window. See style argument for details.

iter_traces(load_data=False, return_abspath=False, group_selector=None, trace_selector=None)

Iterate over all traces in pile.

Parameters:

• load_data – whether to load the waveform data, by default empty traces are yielded
• return_abspath – if True yield tuples containing absolute file path and pyrocko.trace.Trace objects
• group_selector – ignored in squirre-based pile
• trace_selector – filter callback taking pyrocko.trace.Trace objects

snuffle(**kwargs)

Visualize it.

Parameters:

• stations – list of pyrocko.model.Station objects or None
• events – list of pyrocko.model.Event objects or None
• markers – list of pyrocko.gui_util.Marker objects or None
• ntracks – float, number of tracks to be shown initially (default: 12)
• follow – time interval (in seconds) for real time follow mode or None
• controls – bool, whether to show the main controls (default: True)
• opengl – bool, whether to use opengl (default: False)