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[Support #YER-489194]: Re: 20060120: 20060119: 20060118: 20060117: GEMPAK decoder installation

Gilbert,

>I want to store level 2 data for both GEMPAK and WXP. Problem: Level 2
>data sends out chunks of volume scans. Is there any way for me to kick off
>a script when a full volume BREF1 scan arrives from any of KLOT, KILX,
>KMKX and a few other sites? Or SRMV1?
>
>I see you have a script to copy over a full volume scan over, but I'm not
>sure how it works, since I am not familiar with the CRAFT feed.

The CRAFT (aka NEXRAD2) products are broken up into 100 radaial chunks. The 
very last chunk
is identified by the "/E" string appended to the LDM product header.

I have 2 actions, the FILE action writes the chunks out to disk
as they arrive to a file (prepending a "." character to
the file name so that they don't show up in the data listing
because I don't want to display the image until its complete).

The second action keys on the 1 radial which has the "/E" at the end of
the product identifier. When this product is seen, the script (which you can
copy from $NAWIPS/bin/dccraft_move to ~ldm/util) simply moves
the file from the "." prepended file name to the actual file name.
The only purpose of the script is to prevent clobbering an existing file
should you restart your LDM with a new queue and get data again. I just check to
see if a file by the desired output name already exists before moving it. NMAP2
is the primary beneficiary of this, since it auto updates its image loop, if
it sees a file name, it assumes it is ready to go! And, looking at an image with
only 100 radials instead of 360 is somewhat unsatisfying in a loop.

You don't want to try to do level II functions based on when you receive a 
LEVEL III
product since they are independent data streams. Rather, if you use the "/E" 
ending
pattern on the level II, you can move the file on disk (since the file stream 
doesn't care if
the file name changes)- and you could kick off postprocessing (map generation).

Steve Chiswell
Unidata User Support


Ticket Details
===================
Ticket ID: YER-489194
Department: Support GEMPAK
Priority: Critical
Status: Closed