Drastic strategy change: previously, grids where needlessly synthesised from SH expansions, then we performed grid-node-wise operations (i.e. removing the topographic effect from the gravity disturbance). This was both inefficient and required some workarounds.
Main changes:
- reduction for the topographic effect is performed in the SH coefficients domain (using the operator overloading provided by pyshtools classes)
- the only grid synthesis performed is the one from topography reduced field to the relevant grids
- we avoid truncation (the gentle-cut module is left aside), following the Earth2014 Authors recommendation to not do so
- general refactor, leaner environment.yml
- updated documentation (in notebook cells)