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GRIB2 documentation question

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  • Subject: GRIB2 documentation question
  • Date: Wed, 22 Jun 2005 10:19:48 -0600 (MDT)
hello,

Please forward this message to the people in charge of the FM92-GRIB2
documentation.

I work for a NSF funded organization and I am in the process of writing a
GRIB2 decoder in java.  The decoder is in beta stages, checking for minor
problems now. According to the FM92-GRIB2-2005feb.pdf documentation, I
have some questions about the Grid Definition Templates starting with
template 3.10

Template 3.10 Mercator

There is no scale factor stated for:
La1, Lo1, LaD, La2, Lo2

Template 3.20 Polar Stereographic

There is no scale factor stated for:
La1, Lo1, LaD, LoV

Template 3.30 Lambert Conformal

There is no scale factor stated for:
La1, Lo1, LaD, LoV, Latin1, Latin2,
Latitude of the southern pole projection
Longitude of the southern pole projection

Template 3.31 ALbers equal area

There is no scale factor stated for:
La1, Lo1, LaD, LoV, Latin1, Latin2,
Latitude of the southern pole projection
Longitude of the southern pole projection


I'm sure that I missed other Lat/Lon variables for other projections.
Currently, I assume the the Lat/Lon variables are stored as a integer and
that the scale factor is 1/1000000.  This assumption results in reasonable
Lat/Lon values.  I tried reading the variables as a float but the results
are unreasonable values. It would really help a developer if the variables
types were stated in the templates and the scale factor notes were
included with all variables.

Thanks for your time,
Robb...

===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================