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Yes, a netcdf4 file is a valid hdf5 file. Howeverr, HDF5 doesnt understand the shared dimensions. But for many uses, it doesnt matter so much. John > Can netcdf4 files be read by hdf5 readers? because of the interoperability > between the two? > Thanks > Zhenping > > Sent from my iPhone > > > On Feb 11, 2015, at 12:52 PM, Unidata netCDF Java Support <address@hidden> > > wrote: > > > > Can you send the ncdump -h output? > > > > If dimension len > 2^31-1, we dont have a workaround presently. > > > > John > > > >> Here is the java print out the netcdf file (version 4) using the > >> toString() method in netcdf4 java library: > >> > >> netcdf > >> /home/zpli/MLS/G17/L0/Archive/IT_ABI-L0-M03_G17_s20142461945100_e20142462000180_c20142462000204.nc > >> { > >> dimensions: > >> number_of_packets = UNLIMITED; // (6131690 currently > >> number_of_data_bytes = UNLIMITED; // (0 currently > >> variables: > >> int offset_to_packet(number_of_packets=6131690); > >> :long_name = "index in the abi_space_packet_data variable of the start of > >> the packet"; > >> :_ChunkSize = 256; // int > >> > >> float percent_uncorrectable_L0_errors; > >> :units = "percent"; > >> :long_name = "percent uncorrectable L0 errors"; > >> > >> int size_of_packet(number_of_packets=6131690); > >> :long_name = "size of each packet"; > >> :_ChunkSize = 256; // int > >> > >> byte abi_space_packet_data(number_of_data_bytes=0); > >> :long_name = "GOES-R Advanced Baseline Imager (ABI) L0 CCSDS Space > >> Packets"; > >> :coverage_content_type = "physicalMeasurement"; > >> :_ChunkSize = 2048; // int > >> > >> // global attributes: > >> :dataset_name = > >> "IT_ABI-L0-M03_G17_s20142461945100_e20142462000180_c20142462000204.nc"; > >> :naming_authority = "gov.noaa.goes-r"; > >> :iso_series_metadata_id = "a70be540-c38b-11e0-962b-0800200c9a66"; > >> :Conventions = "CF-1.6"; > >> :Metadata_Conventions = "Unidata Dataset Discovery v1.0, CF-1.6"; > >> :standard_name_vocabulary = "CF Standard Name Table (v18, 22 July 2011)"; > >> :title = "Advanced Baseline Imager (ABI) L0 CCSDS data packets"; > >> :summary = "Raw data reconstructed to unprocessed instrument data at full > >> space-time resolution with all available supplemental information to be > >> used in subsequent processing appended."; > >> :keywords = "SPECTRAL/ENGINEERING > INFRARED WAVELENGTHS > SENSOR COUNTS, > >> SPECTRAL/ENGINEERING > VISIBLE WAVELENGTHS > SENSOR COUNTS"; > >> :keywords_vocabulary = "NASA Global Change Master Directory (GCMD) Earth > >> Science Keywords, Version 7.0.0.0.0"; > >> :license = "Unclassified data. Access is restricted to approved users > >> only."; > >> :institution = "DOC/NOAA/NESDIS > U.S. Department of Commerce, National > >> Oceanic and Atmospheric Administration, National Environmental Satellite, > >> Data, and Information Services"; > >> :date_created = "2014-09-03T20:00:20Z"; > >> :processing_level = "National Aeronautics and Space Administration (NASA) > >> L0"; > >> :time_coverage_start = "2014-09-03T19:45:10Z"; > >> :time_coverage_end = "2014-09-03T20:00:18Z"; > >> :timeline_id = "03"; > >> :orbital_slot = "GOES-West"; > >> :platform_ID = "G17"; > >> :instrument_type = "GOES R Series Advanced Baseline Imager"; > >> :instrument_id = "ABI-1"; > >> :production_data_source = "Test"; > >> :production_site = "WCDAS"; > >> :production_environment = "ITE"; > >> :id = "c4420190-4a71-4451-a2a2-b38c2db89296"; > >> } > >> > >> Notice the dimension number_of_data_bytes is unlimited but 0 currently. > >> The actual size is 3374823640 when using the ncdump. In netcdf Java API: > >> getLength() method for Dimension class is defined as int, the number > >> 3374823640 would return as negative for int. Do you have a sample code for > >> work around? Also, the variable offset_to_packet should be defined as > >> unsigned int, so that it could be larger than 0x7FFFFFFF. I am getting the > >> negative output values for this variable. > >> > >> Thanks for your help. > >> > >> Zhenping > >> > >> -----Original Message----- > >> From: Unidata netCDF Java Support [mailto:address@hidden] > >> Sent: Tuesday, February 10, 2015 3:42 PM > >> To: address@hidden > >> Cc: address@hidden; address@hidden > >> Subject: [netCDFJava #CPC-398807]: FW: question about large file support > >> > >> Sorry for jumping in, I hope it is not too confusing. > >> When you say "...when Java reads it, the dimension length is defined as > >> the (signed) integer..." > >> do you mean the netcdf-java library or a program you are writing? > >> If the latter, then it is possible to use the Java long type to properly > >> represent such a number. > >> =Dennis Heimbigner > >> Unidata > >> > >> > >> Ticket Details > >> =================== > >> Ticket ID: CPC-398807 > >> Department: Support netCDF Java > >> Priority: Normal > >> Status: Closed > > > > > > Ticket Details > > =================== > > Ticket ID: CPC-398807 > > Department: Support netCDF Java > > Priority: Normal > > Status: Closed > > > > Ticket Details =================== Ticket ID: CPC-398807 Department: Support netCDF Java Priority: Critical Status: Closed