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Re: netcdf lookup tables

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  • Subject: Re: netcdf lookup tables
  • Date: Mon, 10 Sep 2007 10:28:23 -0600
Hi Arthur:

You can store the lookup tables in netcdf-3, but theres no standard way for an
application to know to use the lookup values. netcdf-4 has enumerated types
which are really a lookup table.

The IOSP can do the lookups of course, so the expansion to floats only happens
if you actually write the original file out to a netcdf file. If thats what you
need to do, i should mention that we wont be able to write to netcdf-4 format
for now, and im not sure when we will be able to.

John

arthur.fotos wrote:

John,
We are currently developing IOSPs for several data formats that contain
lookup tables for temperature, pressure, etc.  The raw data is stored in
bytes.  The value of the byte is used to retrieve the value for
temperature, pressure, etc from tables as a float.  Currently we perform
the lookup and store the values as floats.  The end result is a netcdf
file that is much larger than the original data file.  Using the netcdf
3 format, is there a way to provide the lookup tables and store the data
as bytes?  If its not possible will it be possible in netcdf 4.
thanks
arthur fotos