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 Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated.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.
The -isLargeFile option is now in the lastest 4.1 release at: http://www.unidata.ucar.edu/software/netcdf-java/ under the "Development version 4.1" downloads. You can wrap the original dataset in ncml, and use the <remove> element to remove the ones you dont want, see http://www.unidata.ucar.edu/software/netcdf/ncml/ example at: http://www.unidata.ucar.edu/software/netcdf/ncml/v2.2/Cookbook.html#remove the xml file must have the suffix ".ncml", and it then becomes the "in" file: java -Xmx512m -classpath netcdfAll-4.0.jar ucar.nc2.dataset.NetcdfDataset -in myfile.ncml -out out.nc > Russ: > > Thanks again for the quick response. Actually, I only need the wind field > data (UGRD, VVEL, AND VGRD), and only for a particular geographic subregion. > If there's a way to just convert those data to NetCDF, the -isLargeFile > option won't be necessary. > > I'm just learning how to do this. I'll poke through the NetCDF-Java > documentation. If you know offhand how it would be done and can tell me, > that would be even better. > > Thanks again, > > Larry > > David A. Johnston Cascades Volcano Observatory > 1300 SE Cardinal Court, Bldg. 10, Suite 100 > Vancouver, WA 98683 USA > tel. 360-993-8925 fax 360-993-8980 > http://vulcan.wr.usgs.gov/Projects/Mastin > -----Original Message----- > From: Unidata netCDF Java Support > [mailto:address@hidden] > Sent: Thursday, November 05, 2009 4:41 PM > To: address@hidden > Cc: address@hidden > Subject: [netCDF #HOT-122007]: converting grib2 files to netcdf using wgrib2 > -netcdf > > Hi Larry: > > The problem is that the 2 Gb netcdf file limit is being exceeded (yes it > expands that much!). I will add a -isLargeFile option to allow writing to > the 64-bit offset version. It will take a few days to get teh release out, > ill let you know when its ready. > > > Thanks, Russ. > > > > I downloaded NetCDFAll-4.0.jar from that site and it now finds the main > > class. However I am getting another error message indicating the > > variable starting position is exceeding an allowed value (see below). > > > > My grib2 file is pretty big (383 Mb). Is there a size limit to the > > grib2 files that can be read? > > > > Thanks, > > > > Larry > > > > ******************************************************************* > > Command & error messages below: > > > > lgmastin@phobos:~/ncj> java -Xmx512m -classpath netcdfAll-4.0.jar > > ucar.nc2.dataset.NetcdfDataset -in > > ~/grib2/testfiles/NAM_Alaska_11km_20090920_0600.grib2 -out > > ~/grib2/testfiles/NAM_Alaska_11km_20090920_0600.nc > > Read > > from /home/lgmastin/grib2/testfiles/NAM_Alaska_11km_20090920_0600.grib2 > > write to /home/lgmastin/grib2/testfiles/NAM_Alaska_11km_20090920_0600.nc > > > > Exception in thread "main" java.lang.IllegalArgumentException: Variable > > starting pos=2343709348 may not exceed 2147483647 > > at ucar.nc2.iosp.netcdf3.N3header.writeHeader(N3header.java:626) > > at ucar.nc2.iosp.netcdf3.N3header.create(N3header.java:560) > > at ucar.nc2.iosp.netcdf3.N3iosp.create(N3iosp.java:640) > > at ucar.nc2.NetcdfFileWriteable.create(NetcdfFileWriteable.java:594) > > at ucar.nc2.FileWriter.writeToFile(FileWriter.java:195) > > at ucar.nc2.dataset.NetcdfDataset.main(NetcdfDataset.java:1600) > > > > > > On Thu, 2009-11-05 at 16:11 -0700, Unidata netCDF Java Support wrote: > > > Larry, > > > > > > Alternatively, if from http://www.unidata.ucar.edu/software/netcdf-java/ > > > you had downloaded > > > > > > "The complete netCDF library (MD5) implements the full CDM model, with > all dependent jars included." > > > > > > you would have gotten netcdfAll-4.0.jar file instead of the .zip file > you used, and that would have worked, using: > > > > > > java -Xmx512m -classpath netcdfAll-4.0.jar > ucar.nc2.dataset.NetcdfDataset -in > ~/grib2/testfiles/NAM_Alaska_11km_20090920_0600.grib2 -out > > > ~/grib2/testfiles/NAM_Alaska_11km_20090920_0600.nc > > > > > > --Russ > > > > > > > > > Russ Rew UCAR Unidata Program > > > address@hidden http://www.unidata.ucar.edu > > > > > > > > > > > > Ticket Details > > > =================== > > > Ticket ID: HOT-122007 > > > Department: Support netCDF Java > > > Priority: Normal > > > Status: Closed > > > > > > > > > > Ticket Details > =================== > Ticket ID: HOT-122007 > Department: Support netCDF Java > Priority: Normal > Status: Open > > > > Ticket Details =================== Ticket ID: HOT-122007 Department: Support netCDF Java Priority: Normal Status: Closed