Package v2grid

Extract from the compressed RDNAPTRANS(tm)2018_v229627 variant 2 naptrans2018.txt.zip and rdtrans2018.txt.zip grid files only the NAP_..., lat_corr_ and lon_corr_ columns and encode each in Python as a row-order matrix, a 481-tuple of 301-arrays of single- or double precision floats.