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[netCDFJava #TJD-270946]: HDF5 reader

Hi Chris, thanks for that information. Im looking at a random file example i 
have, happends to be VIIRS. It seems like all the interesting info is 
available, even without the region references. Im wondering if for your 
purposes you need those, or if the way the netcdf-java interface presents the 
info is adequate?

Im also seeing that they have important metadata in external XML files, though 
im not sure how to associate a data file with an XML file. Do you know anything 
about that?

John

> Hello,
> I finally got a response from the NPOESS people about the data that netCDF 
> doesn't currently read.  As near as I could tell, netCDF is capable of 
> reading all the data from the files with the exception of the 
> "<CollectionShortName>_Gran_<n>" data sets.  I figured you may be interested 
> in what NPOESS wrote to me, so here it is.
> 
> "Chris,
> 
> The datasets CollectionShortName_Gran_n, where n is {Agg, 0..# of granules in 
> package}, are basically storage bins of metadata. The dataset portion is a 
> hyperslab that points to datasets in the "AllData" group. The All_Data group 
> contains the raw data.  The reason for the "_0", "_Agg" items is that if the 
> user requested aggregated granules, then there are multiple sets of metadata 
> - sets for each granule, and 1 set for the entire aggregated data.
> 
> If you want to look at only granule-level (not aggregation-level) metadata, 
> then you can ignore the "_Agg" items.
> 
> Thanks,
> Bill"
> 
> The HDF5 libraries decode the data in these data sets to looks something like 
> this:
> [0:7144 {(0)-(11)}, 0:9840 {(0)-(11)}, 0:12208 {(0,0)-(11,95)}, etc...]
> 
> So, if you really wanted too, you could just probably return the data as a 
> String, and let the users determine what they want to do with it.  For me, it 
> looks like our project will not need the data found in that dataset:).
> 
> 
> v/r
> 
> Chris Webb
> Software Engineer, WDAC
> Harris Corporation
> (402) 294-4358
> 
> 
> -----Original Message-----
> From: Unidata netCDF Java Support [mailto:address@hidden]
> Sent: Thursday, July 30, 2009 8:04 PM
> To: Webb, Christopher A CTR USAF AFWA AFWA/WDAC
> Subject: [netCDFJava #TJD-270946]: HDF5 reader
> 
> Hi Chris:
> 
> 
> Release 4.0.48.5 disables HDF5 region references (npoess "granules") for now, 
> until i can figure out how these work. This allows the rest of the dataset to 
> be used. Please let me know if you see any problems. If you understand what 
> use case granules serve, i'd love to know that also.
> 
> thanks!
> 
> 
> Ticket Details
> ===================
> Ticket ID: TJD-270946
> Department: Support netCDF Java
> Priority: Normal
> Status: Open
> 
> 


Ticket Details
===================
Ticket ID: TJD-270946
Department: Support netCDF Java
Priority: Normal
Status: Open