obspy.core.stream.Stream.filter

Stream.filter(type, *args, **options)

Filter the data of all traces in the Stream.

Parameters:

• type (str) – String that specifies which filter is applied (e.g. "bandpass"). See the Supported Filter section below for further details.

• args – Only filter frequency/frequencies can be specified as argument(s). Alternatively filter frequencies can be specified as keyword arguments.

• options – Keyword arguments for the respective filter that will be passed on. (e.g. freqmin=1.0, freqmax=20.0 for "bandpass")

Note

This operation is performed in place on the actual data arrays. The raw data is not accessible anymore afterwards. To keep your original data, use copy() to create a copy of your stream object. This also makes an entry with information on the applied processing in stats.processing of every trace.

Supported Filter

'bandpass'

Butterworth-Bandpass (uses obspy.signal.filter.bandpass()).

'bandstop'

Butterworth-Bandstop (uses obspy.signal.filter.bandstop()).

'lowpass'

Butterworth-Lowpass (uses obspy.signal.filter.lowpass()).

'highpass'

Butterworth-Highpass (uses obspy.signal.filter.highpass()).

'lowpass_cheby_2'

Cheby2-Lowpass (uses obspy.signal.filter.lowpass_cheby_2()).

'lowpass_fir' (experimental)

FIR-Lowpass (uses obspy.signal.filter.lowpass_fir()).

'remez_fir' (experimental)

Minimax optimal bandpass using Remez algorithm (uses obspy.signal.filter.remez_fir()).

Example

>>> from obspy import read
>>> st = read()
>>> st.filter("highpass", freq=1.0)  
<...Stream object at 0x...>
>>> st.plot()  

(Source code, png)