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20040507: GEMPAK 5.7.2p2 available (Level II radar data mods)



GEMPAK users,

I have reposted the latest GEMPAK release as GEMPAK 5.7.2p2 which
now includes the ability for the display programs to access the 
Level II radar products from the CRAFT IDD feedtype in the compressed
BZ2 format and eliminate the need to pipe the data through dcnexr2.

I have modified the pqact.gempak_craft template for filing the data
in $NAWIPS/ldm/etc/templates as follows:

####
# CRAFT stored as raw bz2 for GEMPAK
#
# file the raw data to a temporary file beginning with "." so that autoupdate 
GUIs don't
# get ugly partial volume plots
CRAFT   
^L2-BZIP2/(....)/([0-9][0-9][0-9][0-9][0-1][0-9][0-3][0-9])([0-2][0-9][0-5][0-9])([0-9][0-9])
        FILE    data/gempak/nexrad/craft/\1/.\1_\2_\3
#
# Done to move file after last record is received "/E" to prevent
# autoupdate from seeing partially received files (dccraft_move is a shell 
script copied from $NAWIPS/bin/scripts)
CRAFT   
^L2-BZIP2/(....)/([0-9][0-9][0-9][0-9][0-1][0-9][0-3][0-9])([0-2][0-9][0-5][0-9])([0-9][0-9]).*/E$
        EXEC    util/dccraft_move data/gempak/nexrad/craft/\1/.\1_\2_\3 
data/gempak/nexrad/craft/\1/\1_\2_\3
#
####


Note that the above actions contain 2 steps:
1) a file action to a temporary file beginning with ".".
2) an exec action of a script copied from 
        $NAWIPS/bin/scripts/dcmove_craft
   to rename the product after receiving the last part of the product 
(eg product name ending with "/E"). The script just puts a 
safety check around the "mv".

This is done to avoid the auto update feature of the NMAP gui from
seing the file as a partial volume since the pieces arrive over
a period of time. This prevents ending up with partial (eg 100 degree)
scans instead of a full scan on display). (This was a feature within
dcnexr2 as well).

Also note that until all NEXRAD sites have upgraded to Build 5.0,
those sites transmitting the older format data will not have the station
ID in bytes 21-24 of the product header, and therefore you must make
sure that the LDM file name matches the template of NEXRII in
$GEMTBL/config/datatype.tbl in order to nagivate the displays.
A waring message will be displayed for products that don't have the
station ID in them. The pqact.gempak_craft pattern action
matches the NEXRII template as distributed.

Note for binary users: All display programs and device drivers 
are afected by the change and should be upgraded together
(eg don't just extract gpnexr2 out of the tarfile).

Steve Chiswell
Unidata User Support