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[netCDFJava #NBT-844482]: problems with add_offset, scale



Heather,

Now that I think about it, the raw data in a Level 2 file are unsigned bytes, 
so you shouldn't even be able to get a value of -24.
If I convert -24 to its unsigned byte equivalent, 232, then the scale and 
offset give me 0.975. 

What are you using to read the data back in? Are you converting to a netCDF 
version 3 file or a version 4 file? The version matters, because
netCDF 3 doesn't support unsigned data, so we set an attribute _Unsigned to 
indicate that the data are unsigned; the data type netcdf variable
itself is byte. For netcdf version 4, the data are written as unsigned bytes.

Writing out netcdf version 4 files from netcdf-java requires having the 
netcdf-C library installed and configured, so I'm going to guess you're writing
netcdf version 3 files.

Ryan

> A RhoHV that low wouldn't even be observed with tornado debris.  It's not
> reasonable.  I've checked against another conversion tool and it says the
> RhoHV value at the grid point is 0.975.
> 
> At another grid point, unidata's conversion tool says RhoHV is -125 (before
> the correction, -0.215 after) and the other tool says 0.638333.
> 
> At yet a third grid point, unidata = 50 before and 0.36833335, a value
> which the other tool agrees with.
> 
> I don't know what is going on, but something isn't right in the unidata
> converter.


Ticket Details
===================
Ticket ID: NBT-844482
Department: Support netCDF Java
Priority: Normal
Status: Closed
===================
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NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.