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[LDM #GXI-553029]: LDM move



Hi Bongchul,

re:
> Thank you for the quick response.

No worries.

re:
> 'ldmd.log' is empty in our LDM,

This is a situation that really should be corrected.  Without LDM log output
a significant number (if not most) problems are impossible to diagnose.

re:
> but when we process data, we create some warning
> messages if the data are not fully filled (for example, the message shows 
> number of rays
> in each elevation angle and often indicates 600 rays for some angles, but the 
> full rays
> are 720).

OK.

re:
> I copied our action file and pasted below for one of the radars:
> 
> # KDVN
> CRAFT   
> ^L2-BZIP2/(KDVN)/([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]/[0-9]*/([0-9]*)
> FILE    /home/ldm/data/KDVN/tmp/\1_\2_\3_\4
> CRAFT   
> ^L2-BZIP2/(KDVN)/([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]/[0-9]*/([0-9]*)/E
> EXEC    /home/ldm/bin/makeRadarII.pl \1 \2 \3 \4
> 
> I think that 'makeRadarII.pl' assembles pieces into a full volume.

This processing _assumes_ that the final piece of a volume scan will be
receive last.  Since the change in how Level II data was collected and
relayed by the NWS, one can not assume that the pieces of a volume scan
will be received in order.  I former Unidata staff member, Robb Kambic
(Robb retired in the fall of last year), came up with a workable procedure
to reassemble Level II volume scans from pieces.  The high-level overview
is:

- write all pieces for a volume scan for a station (one and only one
  station) to a directory on disk

- wait for awhile (have to review the procedure to determine how long
  we are waiting), and then run a script that checks to make sure
  that the right number of pieces have been received (easier said
  than done) and then reassemble the volume scan in order

re:
> Was there any update with the script after the dual-pol upgrade?

I thought that Robb worked with someone at U Iowa on this issue
some time ago (I could be wrong).  I know that Jeff Weber was involved
with the Hydro Nexrad project, and the need to be more careful when
collecting and reassembling volume scan pieces was a hot topic of
discussion and work.

I am assuming that you want a step-by-step guide on how to process
the Level II data.  It will take me some time to review what is being
done here for me to describe it to you in enough detail that you can
implement it there.  To get you going (at least thinking about the
process, I am attaching the pattern-action file, pqact.threddsradarlevel2,
and Perl script, hhmmssRadarII.pl, that we are using on our motherlode.ucar.edu
server for Level II processing.  The ~ldm/etc/ldmd.conf file entry
that is used for processing the Level 2 data is:

exec    "pqact -f NNEXRAD|CRAFT etc/pqact.threddsradarlevel2"


Cheers,

Tom
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Ticket Details
===================
Ticket ID: GXI-553029
Department: Support IDD
Priority: Normal
Status: Closed

Attachment: pqact.threddsradarlevel2
Description: Binary data

Attachment: hhmmssRadarII.pl
Description: Perl program