Package v1grid
Variant 1 grid files, but only columns NAP_h_...,
lat_corr_ and lon_corr_ of the original
RDNAPTRANS2018_v220627/...1/nlgeo2018.txt and
...1/rdcorr2018.txt grid files and encoded into Python as 3
row-order matrices, each a 481-tuple of 301-arrays of floats.
Of the 144,781 floats (481 x 301) in each of the
lat_corr_ and lon_corr_ columns of the original
grid file ...1/rdcorr2018.txt only 55,139 respectively
55,348 are non-zero between indices [8598:93827] respectively
[8598:93830].
As a result, the first 28 and the last 169 rows (in total 197 rows or
41% of 481) can all be represented by the same 301-array of
single-precision zeros. There are other stretches of zeros, but none
amount to 301 or more.
The non-zeros in lat_corr_ and lon_corr_
colums are initially stored as a 349- respectively 317-tuple of runs of
non-zeros plus a start and end index. Upon import, the runs are
re-formatted into a row-order matrix, a 481-tuple of 301-arrays of
floats.
The combined size of these 3 grid files is 2 MB vs 9.7 MB for the
original 2.
- pyrdnap.v1grid.nlgeo2018_txt_NAP_h: Variant 1 grid file
...1/nlgeo2018.txt, only
the 3rd column NAP_quasi_geoid_height_...(m) and
encoded in Python as a 481-tuple of 301-arrays of floats.
- pyrdnap.v1grid.rdcorr2018_txt_lat_corr: Variant 1 grid file
...1/rdcorr2018.txt, only
the 3rd column lat_corr_(deg) with
+0.00000* shrunk to 0.*,
-0.00000* to -.* and encoded in Python as
an n-tuple of runs of non-zeros.
- pyrdnap.v1grid.rdcorr2018_txt_lon_corr: Variant 1 grid file
...1/rdcorr2018.txt, only
the 4th column lon_corr_(deg) with
+0.00000* shrunk to 0.*,
-0.00000* to -.* and encoded in Python as
an n-tuple of runs of non-zeros.
|