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 Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated.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.
Greetings David, Did you know that you can subset the full WRF grid in the IDV before you load any data into memory? Once you open the datafile in the IDV, you will be taken to the Field Selector. Before selecting a variable to plot, right click on the data files entry in the Data Source pane (left side of the Field Selector window) and click "Properties." This will bring up a properties box for your WRF output. You can subset spatially and temporarily by clicking on the Spatial Subset and Times tabs. Because the IDV does not actually load any data (other than the metadata) until you tell it to create the display. Will this work for you? Sean > Sir/Madam, > > I have come across an issue I can't seem to resolve but I'm sure has > come up before. I am attempting to subset some specific variables from a > typical netcdf wrf model output file and then view those data in IDV. I > can load view the full wrf output files just fine. I am using netcdf > command operators (nco) to subset variables, specifically 'ncks -v > ...'. However I am unable to load the subsetted netcdf file into IDV > and get a dreaded "No gridded data found" response. I have attached > the subsetted netcdf file to this email as it is not very big. Can you > advise as to why this file is not able to be imported into IDV? It > looks to me like the proper dimension and attribute data have been > copied into the subsetted data file, but perhaps I am missing something. > > The motivation for thinning this data to a couple variables is to reduce > file size and memory reqs. > > I can send you the full wrf output file if necessary. > > Thank you, > Dave Gochis > > Ticket Details =================== Ticket ID: TFK-746246 Department: Support IDV Priority: Normal Status: Open