NOAA / NWS's Meteorological Development Laboratory
Degrib (NDFD GRIB2 Decoder)
Subject: Degrib 1.23
Date: Thu, 31 Jul 2003 21:45:27 -0400
Organization: DOC/NOAA/NWS - National Weather Service
You all have the unique distinction of being registered on my degrib
(aka NDFD_GRIB2Decoder) mailing list (all 119 of us) (I'd like to
welcome: williama, mkienzle, chuck, alton, jdperez, dzc66, john.kozimor,
Daniel.Konde, and ken.waters)
Please let me know (email me) if you want to unregister.
I just wanted to let you all know that I have just finished putting
together version "1.23" (last one that I announced was "1.22" on
The latest version of the program is on:
News about this release:
1) I found a REALLY cool memory checker at :
"http://www.gnu.org/directory/devel/debug/memwatch.html". After using
it I found I had two memory leaks. I will now be using memwatch as a
backup to my normal coding.
2) Resolved a bug where I could convert a message in the GIS tab, but
then I couldn't generate any images.
3) Resolved the "Ken Waters and Jamie Perez" space bug. They each tried
to install to a path with a "space" in it, such as "c:/program
files/ndfd/". It is now believed to be possible to do that...
4) Added defense for the case where there are more Temperature messages
than Wind messages.
5) Found out that although NCEP said they used 6367.47 km for the radius
of earth in the GRIB1 and GRIB2 documentation, they actually use 6371.2
km (found this out via email, and asking them to check their code)
(Note: 6371.2 km is what is hard-wired in GrADS). In GRIB1 there is no
way to specify the 6371.2 km radius, so I am now providing a -radEarth
option to allow users to "override" the radius specified in the GRIB
file. For GRIB2 they can specify the correct one, and it is believed
that NDFD (and AWIPS / GFE / etc) use a spherical earth with radius
6371.2 km. I'm not sure if / when the NDFD GRIB2 encoder will be
updated to use 6371.2 km. To find out what radius of Earth a given GRIB
message claims, use the -Met option and look in the resulting .txt file
(in the GDS section).
6) Adjusted Wave Height output, using the "-unit e" flag (e is for
english as opposed to metric), to be in feet (instead of meters).
7) Hopefully fixed the "wintry mix" bug with weather (there shouldn't be
wintry mix in the summer :-) ) The current thought is that the bug was
due to not initializing a data structure correctly. This bug is a
phantom who keeps appearing... Hopefully I've slain it for the last
8) Improved the method used to determine the reference time for a given
GRIB file, by looking at only the first message, instead of all
messages. This assumes that all the messages in the file have the same
reference time, but it is a safe assumption, and it is only used for the
"X hours old display".
9) Added calls to superImageGen. This program allows one to create all
the mosaic's first, and then generate all the images. This should be
faster than imageGen, which generated only 1 image at a time, because of
fewer "execs" and because superImageGen can keep some information in
memory between image draws.
10) Updated the Help definitions and color tables, used by htmlmaker and
As always, I tested this release on my PC (win 2000), a Linux machine, a
HP-Unix machine, and an AIX-Unix (machine). Although I may have missed
something in my testing, it should at least compile, and run for some of
the test cases. For those of you with access to the NWS NCEP machine,
my current version is in: /nfsuser/g06/we25at/degrib (on snow/frost).
For those with access to MDL's GDP or NHDW machines, see:
Please let me know if you have problems.