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I've noticed a problem when using gdalwarp to warp netCDF data sets
to different resolutions.<br>
$ gdalwarp --version<br>
GDAL 1.11.0, released 2014/04/16<br>
It also happens with:<br>
$ gdalwarp --version<br>
GDAL 1.9.2, released 2012/10/08<br>
<br>
It makes no difference if I'm warping to a higher, lower or same
resolution, all the data points from -180 to 90 longitude are set to
the noData value.<br>
The only points that remain unaffected are those that equal 0. If I
set all points that are 0 to 1, then every point <90deg longitude
is set to the nodata value.<br>
<br>
I have seen this before, but specifying the -srcnodata and
-dstnodata values fixed it in those cases, it seems to have no
affect on the dataset I'm using now.<br>
One of the versions of the commands I've used, doesn't seem to
matter which resampling method I use.<br>
$ gdalwarp -r cubicspline -tr 0.1 -0.1 -dstnodata -9999 -srcnodata
-9999 -of netCDF in.nc out.nc<br>
<br>
Does anyone have any idea what's going on here?<br>
<br>
Input file info (output file info is the same, except (pixel) size
changes)<br>
<blockquote><small>Driver: netCDF/Network Common Data Format</small><br>
<small>Files: in.nc</small><br>
<small>Size is 8640, 3432</small><br>
<small>Coordinate System is:</small><br>
<small>GEOGCS["WGS 84",</small><br>
<small> DATUM["WGS_1984",</small><br>
<small> SPHEROID["WGS 84",6378137,298.257223563,</small><br>
<small> AUTHORITY["EPSG","7030"]],</small><br>
<small> TOWGS84[0,0,0,0,0,0,0],</small><br>
<small> AUTHORITY["EPSG","6326"]],</small><br>
<small> PRIMEM["Greenwich",0,</small><br>
<small> AUTHORITY["EPSG","8901"]],</small><br>
<small> UNIT["degree",0.0174532925199433,</small><br>
<small> AUTHORITY["EPSG","9108"]],</small><br>
<small> AUTHORITY["EPSG","4326"]]</small><br>
<small>Origin = (-180.000000000000000,85.000000000114412</small><br>
<small>Pixel Size = (0.041666666666700,-0.041666666666700)</small><br>
<small>Corner Coordinates:</small><br>
<small>Upper Left (-180.0000000, 85.0000000) (180d 0' 0.00"W,
85d 0' 0.00"N)</small><br>
<small>Lower Left (-180.0000000, -58.0000000) (180d 0' 0.00"W,
58d 0' 0.00"S)</small><br>
<small>Upper Right ( 180.0000000, 85.0000000) (180d 0' 0.00"E,
85d 0' 0.00"N)</small><br>
<small>Lower Right ( 180.0000000, -58.0000000) (180d 0' 0.00"E,
58d 0' 0.00"S)</small><br>
<small>Center ( 0.0000000, 13.5000000) ( 0d 0' 0.00"E,
13d30' 0.00"N)</small><br>
<small>Band 1 Block=8640x1 Type=Float32, ColorInterp=Undefined</small><br>
<small> NoData Value=-9999</small><br>
<br>
<br>
</blockquote>
Thanks,<br>
<br>
Jerl<br>
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