search

fatiando / harmonica

Forward modeling, inversion, and processing gravity and magnetic data
https://www.fatiando.org/harmonica
BSD 3-Clause "New" or "Revised" License
208 stars 68 forks source link

Compute horizontal derivatives of grids using finite differences #378

Closed santisoler closed 1 year ago

santisoler commented 1 year ago

Make functions derivative_easting and derivative_northing to compute the horizontal derivatives using central finite-differences through the xarray.DataArray.differentiate method by default. Add a method argument to let users choose if they want to use the FFT implementation or the finite differences one. This implementation mimics the one we had in the old fatiando.

santisoler commented 1 year ago

@LL-Geo, I'm planning to merge this PR during this week. If you have the chance to take a look at it, that would be nice. Otherwise, don't worry, we can always change this code afterwards.

Since horizontal derivatives using finite differences in the grid are more accurate than their FFT counterpart, I think it might be better to offer the finite differences option as the default one. This was also the default behavior in the old fatiando horizontal derivatives functions.

santisoler commented 1 year ago

@LL-Geo, I'm merging this so I can start the release of Harmonica. Don't worry about the review. If you find something we should change, feel free to open an issue or a pr! Thanks again for all the work with the fft filters!

LL-Geo commented 1 year ago

Just had a quick look! That looks great! 👍