Fileout netCDF cannot generate a valid netCDF file when string datatype has a _FillValue
Description
FilenetCDF out fails to generate either a netcdf3 or a netcdf4 for OMPS due to a string datatype variable has a _FillValue. I can confirm this is not a netCDF bug since netCDF’s nccopy can successfully generate a netCDF-3 file. It is a bug inside the filenetCDF out. I use NcML to rename the _FillValue to _FillValueStr, then I can successfully generate nc-4 or nc-3 files.
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GeolocationData_UTC_CCSDA_A
{
String long_name "UTC Image Midpoint Time";
String coverage_content_type "referenceInformation";
String _FillValue "0000-00-00T00:00:00.000000Z";
String valid_range "2012-01-01T00:00:00.000000Z", "2099-12-31T00:00:00.000000Z";
String DIMENSION_LABELS "DimAlongTrack";
String origname "UTC_CCSDA_A";
String fullnamepath "/GeolocationData/UTC_CCSDA_A";
}Using NCML I can change the string _FillValue to another name and generate netCDF-4 or netCDF-3 files.
http://alpaca:8080/opendap/hyrax/data/ncml/ges_2017_eval/rename_string_fillvalue.ncml.html
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<?xml version="1.0" encoding="UTF-8"?>
<netcdf location="/data/hdf5/ges-2017/OMPS/OMPS-NPP_NMNO2-L2_2017m0101t000532_o26838_2017m0309t171152.h5" xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2">
<!-- Although variable@type attribute is technically required by the schema, i have been
using type="" to mean "whatever type a variable with the given name has" -->
<variable name="GeolocationData_UTC_CCSDA_A">
<!-- Rename attribute _FillValue -->
<attribute name="_FillValue_str" orgName="_FillValue" />
</variable>
</netcdf>Environment
None
