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[netCDF #OCR-368719]: Errors opening thredds aggregation url

The immediate cause is this.
If you look at this in a browser:
https://mynasadata.larc.nasa.gov/thredds/dodsC/sealevelheight.das
you will see that a _FillValue attribute is present in, for example,
the sea_level variable.
This is currently disallowed because the file is read-only
and because it is being translated to netcdf-3, which
technically has no way to set the fill value.
I think this is the wrong behavior in this case, but I need to
think about the proper way to handle this. For what it's worth, I
suspect the DAP4 code has the same problem.
I have create a github issue for this.
https://github.com/Unidata/netcdf-c/issues/924

There is no easy workaround unless you can get the server to not
send the _FillValue.


> Hello,
> 
> I am trying use the netCDF C library to access this url:
> 
> https://mynasadata.larc.nasa.gov/thredds/dodsC/sealevelheight
> 
> With netcdf 4.4.0 this is successful
> 
> > ./ncdump  -version
> ...
> netcdf library version 4.4.0 of Apr  5 2018 10:20:18 $
> 
> > ./ncdump -h https://mynasadata.larc.nasa.gov/thredds/dodsC/sealevelheight
> netcdf sealevelheight {
> dimensions:
>         latitude = 180 ;
>         longitude = 360 ;
>         ntime = 721 ;
>         time = 1 ;
> variables:
>         int woce_date(time) ;
>                 woce_date:long_name = "WOCE date" ;
>                 woce_date:units = "yyyymmdd" ;
>                 woce_date:data_min = 20020729 ;
>                 woce_date:data_max = 20020818 ;
>                 woce_date:FORTRAN_format = "I8" ;
>                 woce_date:time_interval = "five days" ;
>                 woce_date:comment = "gaussian search radius ?10 days" ;
>         float woce_time(time) ;
>                 woce_time:long_name = "WOCE time" ;
> ...
> 
> 
> With later versions it fails,
> 
> > ./ncdump -version
> ...
> 
> netcdf library version 4.6.0 of Apr  5 2018 10:22:05 $
> 
> > ./ncdump -h https://mynasadata.larc.nasa.gov/thredds/dodsC/sealevelheight
> /home/users/ansley/local/dunkel_64_nc46/bin/ncdump:
> https://mynasadata.larc.nasa.gov/thredds/dodsC/sealevelheight: NetCDF:
> Invalid argument
> 
> 
> -or, is there something about that url that's invalid which I could
> report to my contact there?  Other URL's on their server seem to be
> working ok with either version of netcdf libraries, e.g.
> https://mynasadata.larc.nasa.gov/thredds/dodsC/avhrr_sst_agg
> 
> 
> Ansley Manke
> 
> 

=Dennis Heimbigner
  Unidata


Ticket Details
===================
Ticket ID: OCR-368719
Department: Support netCDF
Priority: Normal
Status: Open
===================
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