harmonica.filters.gaussian_highpass_kernel
harmonica.filters.gaussian_highpass_kernel¶
- harmonica.filters.gaussian_highpass_kernel(fft_grid, wavelength)[source]¶
Filter for Gaussian high-pass in frequency domain
Return a
xarray.DataArray
with the values of a Gaussian high-pass filter the frequency domain. The filter is built upon the frequency coordinates of the passedfft_grid
and is defined as follows:where
is the wavenumber vector ( where is the frequency vector) and is the cutoff wavenumber: , where is the cutoff wavelength.- Parameters
fft_grid (
xarray.DataArray
) – Array with the Fourier transform of the original grid. Its dimensions should be in the following order: freq_northing, freq_easting. Usexrft.xrft.fft
andxrft.xrft.ifft
functions to compute the Fourier Transform and its inverse, respectively.wavelength (float) – The cutoff wavelength for the high-pass filter. Its units should be the inverse units of the coordinates in
fft_grid
.
- Returns
da_filter (
xarray.DataArray
) – Array with the kernel for the Gaussian high-pass filter in frequency domain.
References
See also