pycnogrid - Flexible Pycnophylactic Interpolation to Discrete Global and
Local Grid Systems
Provides tools for pycnophylactic interpolation of polygon
totals to discrete global and local grid systems. The method
follows Tobler (1979) <doi:10.1080/01621459.1979.10481647>,
preserving source-zone totals while smoothing values across
neighboring target cells.