harmonica.derivative_easting
harmonica.derivative_easting¶
- harmonica.derivative_easting(grid, order=1, method='finite-diff')[source]¶
Calculate the derivative of a regular grid in the easting direction
Compute the spatial derivative in the easting direction of regular gridded data. It can compute using accurate central differences using
xarray.differentiate
or through frequency domain calculations through Fast Fourier Transform.Important
Choosing the finite differences option produces more accurate results without border effects.
- Parameters
grid (
xarray.DataArray
) – A two dimensionalxarray.DataArray
whose coordinates are evenly spaced (regular grid). Its dimensions should be in the following order: northing, easting. Its coordinates should be defined in the same units.order (int) – The order of the derivative. Default to 1.
method (str (optional)) – Method that will be used for computing the easting derivative. It can be either
"finite-diff"
, for computing usingxarray.differentiate
, or"fft"
, for using FFT-based filters. Default"finite-diff"
.
- Returns
derivative (
xarray.DataArray
) – Axarray.DataArray
with the easting derivatives of the passedgrid
. Its units are the same units of thegrid
per units of its coordinates to the power of the passedorder
.
References