This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
Hi Simon, sorry that I havent been clear enough: True: nj22 implements the CDM data access layer the CDM data access layer is the same as the NetCDF-4 data model Not true (yet):nj22 implements NetCDF-4 Details:
When the NetCDF-4 file format is finalized (waiting on HDF5-1.8), then nj22 will be able to read NetCDF-4. It will not immediately be able to write, and depending on how complicated things are (HDF5 is pretty complicated, esp compared to netcdf-3), it may end up only only writing a subset of netcdf-4. I would guess eventually it will write the whole thing, but that will depend on funding. There has never been an independent library that writes (or reads) HDF5, so we are wary of promising what hasnt been done before. We have prototyped HDF5 reading enough to know we can do that. John Simon Wood wrote:
Hi,I'm trying to clarify the functionality of the latest release of nj22 (eg nj-2.2.17) WRT netCDF-4.According to some of the CDM docs I've seen (eg http://www.unidata.ucar.edu/staff/caron/presentations/CDM.ppt, slide 39) nj22 implements the CDM data access layer (ie netCDF-4) 'to beta quality' but is awaiting HDF5-1.8. I assumed this to mean both reading *and* writing, yet on the the nj22 web page (http://www.unidata.ucar.edu/software/netcdf-java/) it seems to be suggested that only reading of netCDF-4 files is supported with writing being restricted to netCDF-3. Which is correct? Or have I missed something here?regards Simon Wood
=============================================================================== To unsubscribe netcdf-java, visit: http://www.unidata.ucar.edu/mailing-list-delete-form.html ===============================================================================