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[netCDF #BUX-993575]: add_offset definition wrong

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  • Subject: [netCDF #BUX-993575]: add_offset definition wrong
  • Date: Fri, 02 Jan 2009 15:06:30 -0700
Hi,

The situation with add_offset turned out to be more complicated than
I thought, but the section on Packed Data Values in the Best Practices
document has now been replaced:

  
http://www.unidata.ucar.edu/netcdf/docs/BestPractices.html#Packed%20Data%20Values

There is a backward compatibility problem with existing data that assumes
bytes are unsigned when read with the nc_get_var_uchar() function, for
example, so the old formula has to be preserved, but we've also added new
material on the correct definition to use when packed values are assumed
to be signed.

Please let us know if you see more problems with it, and thanks for the
feedback!

--Russ

Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: BUX-993575
Department: Support netCDF
Priority: High
Status: Closed