import dascore
pa = dascore.get_example_patch()
# Apply a notch filter along time axis to remove 60 Hz
filtered = pa.notch_filter(time=60, q=30)
# Apply a notch filter along distance axis to remove 5 m wavelength
filtered = pa.notch_filter(distance=0.2, q=10)
# Apply a notch filter along both time and distance axes
filtered = pa.notch_filter(time=60, distance=0.2, q=40)
# Optionally, units can be specified for a more expressive API.
from dascore.units import m, ft, s, Hz
# Apply a notch filter along time axis to remove 60 Hz
filtered = pa.notch_filter(time=60 * Hz, q=30)
# Apply a notch filter along distance axis to remove 5 m wavelength
filtered = pa.notch_filter(distance=5 * m, q=30)notch_filter
notch_filter(
patch: Patch ,
q ,
**kwargs ,
)-> ‘PatchType’
Apply a second-order IIR notch digital filter on patch’s data.
A notch filter is a band-stop filter with a narrow bandwidth (high quality factor). It rejects a narrow frequency band and leaves the rest of the spectrum little changed.
Parameters
| Parameter | Description |
|---|---|
| patch | The patch to filter |
| q |
Quality factor (float). A higher Q value means a narrower notch, which targets the specific frequency more precisely. A lower Q results in a wider notch, meaning a broader range of frequencies around the specific frequency will be attenuated. |
| **kwargs |
Used to specify the dimension(s) and associated frequency and/or wavelength (or equivalent values) for the filter. |
Note
See [scipy.signal.iirnotch] (https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal.iirnotch.html) for more information.