Aaron, I can confirm your findings. Note that the absence of a _FillValue implies that, as far as I know, the default for that data type is used. I have had user feedback that an explicit _FillValue is preferred to make the file more self documenting and to reinforce its use a missing value (and I think some also like a matching missing_value attribute).
There are more WCS NetCDF output problems: - The GeoServer web UI lacks a means to set variable attributes for NetCDF output; only global attributes can be set. - The dimension Units setting appears to be ignored; Unit Symbol being used instead. - Custom dimension units are encoded as "FIXME" when not set. - There is no way to set other attributes on dimensions, despite some of these being mandatory for CF-1.6 compliance, such the the positive attribute for vertical dimensions. The lack of attribute support is a killer when using a vertical sigma coordinate because there is nowhere to record the formula_terms that define it. The dimension problems become more evident when using ImageMosaic to add extra dimensions. There is no point setting a global Conventions until the above issues are addressed and CF-1.6 compliance is possible. Contributions to improve the fidelity and configurability of NetCDF output would be most welcome. Kind regards, Ben. On 10/12/16 11:30, Aaron Braeckel wrote: > Hello, > > GeoServer 2.9.1 and most other recent versions seem to lose some netCDF > (netcdf-extension) and GRIB (grib-extension) metadata on variables when the > data is retrieved as netCDF (netcdf-out-extension). Note that I am using > netCDF terminology throughout this email. > > For example, in the gs-netcdf-out module (master/today) > WCSNetCDFTest::testRapNativeGribRotatedPole() reads in the rap-native.grib2 > file and writes it out as netCDF. I've attached the CDL of the input and > output for each, and the most important information that is missing from > the Temperature_surface variable in the output is: > > - The "coordinates" attribute > - Grib_* attributes (useful to some consumers) > - The "long_name" attribute > - And it appears all attributes on variables other than "units", > "_FillValue", and a few others > > Global attributes (such as "Originating_or_generating_Center") are also > missing and important, but these can be configured for inclusion through > the GeoServer web UI. > > I am familiar with the netCDF Java API and happy to dig in to the code and > submit a patch, if appropriate, but I am a new developer to GeoServer and > it is unclear to me how these attributes on the variable might best be > passed along to the NetCDFOutputManager. Setting GridCoverage2D > "properties" might be a candidate but I want to check with those more > familiar with the codebase to be sure. > > Do you have any suggestions or cautions for adding this capability to > GeoTools/GeoServer? > > Thanks, > Aaron > > > > ------------------------------------------------------------------------------ > Developer Access Program for Intel Xeon Phi Processors > Access to Intel Xeon Phi processor-based developer platforms. > With one year of Intel Parallel Studio XE. > Training and support from Colfax. > Order your platform today.http://sdm.link/xeonphi > > > > _______________________________________________ > Geoserver-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/geoserver-devel > -- Ben Caradoc-Davies <[email protected]> Director Transient Software Limited <http://transient.nz/> New Zealand ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today.http://sdm.link/xeonphi _______________________________________________ Geoserver-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-devel
