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 Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated.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 John, > In > > http://www.unidata.ucar.edu/software/thredds/current/netcdf-java/documentation.htm > > it says "The NetCDF-Java library is a 100% Java framework for reading > netCDF and other file formats into the CDM, as well as writing to the > netCDF-3 file format." > > So, does it not write to the netCDF-4 file format? Can NetCDF-4 features > be created using this library? If not, what is recommended instead? I've > read the excellent FAQ, and while it lists a number of conversion options, > it doesn't seem to address this directly. Further down in the web page referenced above, it says: Writing to netCDF-4 format is supported, if you have the netCDF C library loaded. As of 4.3.14, this is BETA software. This is a work in progress, using JNA. You can get more information on remaining issues from address@hidden or by looking at the netCDF-4 related issues here: https://bugtracking.unidata.ucar.edu/browse/TDS > Anticipating the answer might involve other non-Java libraries, I am > wondering if there are functional differences between the different > downloads (Java, C, C++, Fortran). If there are, should those be > summarized (or pointed to) at > > http://www.unidata.ucar.edu/downloads/netcdf/index.jsp > > and in the FAQ? The C++, and Fortran APIs are built on top of the C library and are intended to implement the same data model. Our five-year plans include reconciling differences in C and Java data models. Here is a two-way mapping between the netCDF-4 and CDM data models that lists the differences: http://www.unidata.ucar.edu/software/thredds/current/netcdf-java/CDM/Netcdf4.html You're right that it would be good to have a reference to this in the downloads page. Also the FAQ for C-based netCDF software should include more information about the current state of netCDF-Java software, though there are over a dozen references to netCDF-Java interspersed among the answers. > Having mentioned the downloads page, I'd like to suggest that it reference > the FAQ entry > > http://www.unidata.ucar.edu/software/netcdf/docs/faq.html#howtoget > > which mentions other sources. Good idea, thanks! > And having mentioned the FAQ, I note the Table of Contents section has > some text oddly appearing just before Installation and Porting. Hmm, all I see is the bulleted link Is there a document describing the actual physical format for a Unidata netCDF file? Maybe someone else already fixed what you're seeing? --Russ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: VQO-244906 Department: Support netCDF Priority: Normal Status: Closed