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>From: address@hidden >Organization: EPA >Keywords: 200304071857.h37Ivn7U019251 IDV netCDF files John- >Don: If you already know that IDV cannot access these types >of NETCdf files, then just ignore this message ... But if any one >if these files are supposed to be "accessible" and "interpretable" >by IDV than let me know... (There might be something incorrect in >the way that I might be trying to "open" them)... > >The following files were not accessible by IDV: > > > (See attached file: 03030920_buoy.nc) (See attached file: >20030318_USData_test_CO.nc) (See attached file: model_rossby_new.cdf) >(See attached file: 20030318_USData_test_rh.nc) > > >(Comment: I did notice that the first three bytes of NETCdf files >turned out to be "CDF" ... which to me > means that the file is supposedly a NETCDF file.... I also understand >that as Stuart had mentioned to >me that not all NETCDF files are "readable" by IDV... But these enclosed >files are only "FYI", or in case >there's something about them that are supposed to be "readable" or >"interpretable" by IDV........ Thanks), netCDF files must conform to certain conventions to be able to be read into the IDV. Unfortunately, many netCDF files do not adhere to these. For the particular files you sent, here is what I found: 03030100_metar.nc - The IDV handles this type of file if there is sufficient metadata included. In this particular file, there are is no lat/lon info for any of the reports. 03030920_buoy.nc - this is similar to the metar files and will be supported in the next release. For these types of files, we rely on the naming convention (not a good method, but it works until we get something better). I've added .*_buoy.nc to the list of files read by the NetcdfMetarDatasource and was able to plot this file. 20030318_USData_test_rh.nc - I was able to read this file in okay and plot contours. Was there a particular display you couldn't get working? One note, however is that the units for RHUM are invalid. ("fraction[0-1]"). 20030318_USData_test_CO.nc - In this one, the vertical level unit is invalid ("ln(p0/p)"). The IDV can now can only handle vertical units of pressure and altitude. model_rossby_new.cdf - This is a cross section line or something other than a 3D grid. In what way would you want to display such a file? We are always looking to improve the number and scope of netCDF files that we can handle and examples like this are useful. Thanks for passing these along. Don Murray