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 =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.
NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.