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[netCDFJava #JSN-352871]: lookup tables in NetCDF

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  • Subject: [netCDFJava #JSN-352871]: lookup tables in NetCDF
  • Date: Fri, 03 Feb 2012 06:29:03 -0700
Greetings Mario!

There are a few ways you could go about doing this.

The first way is to simply put your lookup table into the netCDF file. For 
clarity, I would add an ancillary_variables attribute to the integer climate 
class variable that points to the variable holding your lookup table 
information 
(http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.6/ch03s04.html). However, 
there really isn't a standard way for applications to know how to use the 
lookup value, so it will be up to you to document your data format to make sure 
others understand what is going on with climate class variables.

The second approach would extend the first by writing and I/O Service Provider 
(IOSP) for your data (see section 4 of the netCDF-Java tutorial 
http://www.unidata.ucar.edu/software/netcdf-java/tutorial/ for more info). In 
this situation, you would extend the reading capabilities of netCDF-Java to 
handle the lookup for your specific type of data file. This would allow you to 
create a method to do the lookup for the user.

A third way (but non-Java) would be to use enumerated types in 
netcdf-4(http://www.unidata.ucar.edu/software/netcdf/workshops/2011/groups-types/EnumCDL.html).
 This method, however, is not usable from netCDF-Java, as the netCDF-4 enhanced 
data model is not supported at this time.

Hopefully this will give you a few ideas. Cheers!

Sean

> Dear support team,
> 
> I've already sent an email to the mailing list. Unfortunately I did
> not get an answer which is why I am writing this mail to you.
> 
> I am currently implementing a climate classification algorithm using
> the NetCDF-Java 4.2 API. The climate class is stored as an integer
> value.
> I'ld now like to know if there is a way to associate the integer
> values with the name of the corresponding climate class, using
> something like a lookup-table?
> 
> I would be glad if you could send me a code example.
> 
> Thanks a lot,
> Mario
> 
> 


Ticket Details
===================
Ticket ID: JSN-352871
Department: Support netCDF Java
Priority: Urgent
Status: Open