Opened 14 months ago

#3672 new defect

r.in.gdal -a and the imported map's east boundary

Reported by: Nikos Alexandris Owned by: grass-dev@…
Priority: normal Milestone:
Component: Raster Version: unspecified
Keywords: r.in.gdal Cc:
CPU: Unspecified Platform: Unspecified

Description

I downloaded the hourly 5km LST product "g2_BIOPAR_LST_201606220100_GLOBE_GEO_V1.2.nc" from Copernicus (see also the product's user manual: https://land.copernicus.eu/global/sites/cgls.vito.be/files/products/GIOGL1_PUM_LST-I1.40.pdf)

The reported pixel size and boundary coordinates for the "LST" layer, are:

gdalinfo NETCDF:"g2_BIOPAR_LST_201606220100_GLOBE_GEO_V1.2.nc":LST |grep Pixel

Pixel Size = (0.044642858207226,-0.044642858207226)

and

gdalinfo NETCDF:"g2_BIOPAR_LST_201606220100_GLOBE_GEO_V1.2.nc":LST |grep Coordinates -A5

Corner Coordinates:
Upper Left  (-180.0223214,  80.0223214) (180d 1'20.36"W, 80d 1'20.36"N)
Lower Left  (-180.0223214, -79.9776824) (180d 1'20.36"W, 79d58'39.66"S)
Upper Right ( 179.9776872,  80.0223214) (179d58'39.67"E, 80d 1'20.36"N)
Lower Right ( 179.9776872, -79.9776824) (179d58'39.67"E, 79d58'39.66"S)
Center      (  -0.0223171,   0.0223195) (  0d 1'20.34"W,  0d 1'20.35"N)

Importing the "LST" layer without any region-related flag, preserves the original spatial resolution. The command

r.in.gdal in=NETCDF:"g2_BIOPAR_LST_201606220300_GLOBE_GEO_V1.2.nc":LST output=g2_BIOPAR_LST_201606220300_GLOBE_GEO_V1.2.nc_LST -o

WARNING: Datum <unknown> not recognised by GRASS and no parameters found
Over-riding projection check
360 degree EW extent is exceeded by 0.000192261 cells
Importing raster map <g2_BIOPAR_LST_201606220300_GLOBE_GEO_V1.2.nc_LST>...
100%

results in

r.info g2_BIOPAR_LST_201606220300_GLOBE_GEO_V1.2.nc_LST -g

360 degree EW extent is exceeded by 0.00019226 cells
north=80.0223214291667
south=-79.9776823855556
east=179.977687153889
west=-180.022321429167
nsres=0.0446428582072328
ewres=0.0446428582072241
rows=3584
cols=8064
cells=28901376
datatype=CELL
ncats=0

The west & east boundaries -180.022321429167 & 179.977687153889 are close to the metadata-reported ones -180.0223214 & 179.9776872.

However, importing with the -a flag,

r.in.gdal in=NETCDF:"g2_BIOPAR_LST_201606220100_GLOBE_GEO_V1.2.nc":LST out=import_with_a -o --o -a

results in

r.info import_with_a -g

north=80.0223333333333
south=-79.9634444444444
east=179.945666666667
west=-180.022333333333
nsres=0.0446388888888889
ewres=0.0446388888888889
rows=3584
cols=8064
cells=28901376
datatype=CELL
ncats=0

the east boundary 179.945666666667 is "far" from what it should expectedly be: 179.977687153889 - 179.945666666667 = 0.03202049.

See also: https://lists.osgeo.org/pipermail/grass-user/2018-October/079239.html

Change History (0)

Note: See TracTickets for help on using tickets.