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[LDM #LJY-425624]: NEXRAD Level II Feed

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  • Subject: [LDM #LJY-425624]: NEXRAD Level II Feed
  • Date: Tue, 03 Jun 2008 14:30:53 -0600
Alan,

> I apologize, I made an assumption that it was fairly common knowledge
> about the NCDC NEXRAD archive.  NCDC has always unbzipped the files,
> accumulate the radial files, then compress them using standard unix
> compress and tar them into 8 hour tar files.  This will change with the
> SuperRes from 8 hour tar files to one hour tar files and gzip instead of
> unix compress.

That knowledge probably is common.  Just shows you how much I get out. :-)

> I run two pqacts simultaneously.   pqact_1.conf entry:
> 
> # NEXRAD Level II  L2-BZIP2/KTBW/20080320021133/100/29/E
> NEXRAD2
> ^L2-BZIP2/((K[ACEGIKMOQSUWY]..)/(........)(......)/(.|..|...)/(.|..|...)($|/E$))
> PIPE    -close  /proc_sm/gtsnp/bin/gtsnp_nr2decomp nr2_\2\3_\4 \1
> 
> and pqact_2.conf entry:
> # NEXRAD Level II
> NEXRAD2
> ^L2-BZIP2/((K[BDFHJLNPRTVXZ]..)/(........)(......)/(.|..|...)/(.|..|...)($|/E$))
> PIPE    -close  /proc_sm/gtsnp/bin/gtsnp_nr2decomp nr2_\2\3_\4 \1
> NEXRAD2 ^L2-BZIP2/(([^K]...)/(........)(......)).(.|..)/(.|..|...)($|/E$)
> PIPE    -close  /proc_sm/gtsnp/bin/gtsnp_nr2decomp nr2_\2\3_\4 \1
> 
> The software used is Harry Edmond's nexradII C program that has been
> slightly updated with NSSL's input.  I can provide it if you like.
> 
> The shell script gtsnp_nr2decomp is very simple:
> 
> #!/bin/sh
> #gtsnp_nr2decomp will decompress the nexrad file received from the network.
> # A file that does not have a begining will not be processed.
> gtsnpHOME=/proc_sm/gtsnp
> gtsnpDATA=$gtsnpHOME/data
> gtsnpTMP=$gtsnpHOME/tmp
> gtsnpLOG=$gtsnpHOME/logs
> gtsnpLAT=$gtsnpHOME/lats
> gtsnpLOGFN=$gtsnpLOG/$(date '+%Y%m%d').nr2decomp
> if [ ! -a $gtsnpLOGFN ];then
> touch $gtsnpLOGFN
> fi
> gtsnpSEQFN=$gtsnpLOG/$(date '+%Y%m%d').nr2seq
> if [ ! -a $gtsnpSEQFN ];then
> touch $gtsnpSEQFN
> fi
> 
> gtsnpSHM=/dev/shm
> export PATH=$gtsnpHOME/bin:$PATH
> 
> gtsnpFN=$gtsnpSHM/$1
> gtsnpRAD=$(echo $2 |cut -f4 -d'/') #number of 100 Radials   i.e. $2 =
> KGSP/20041104151754/160/17
> gtsnpVS=$(echo $2 |cut -f3 -d'/') #Volume scan
> gtsnpEND=$(echo $2 |cut -f5 -d'/') #E if this is the end
> gtsnpSID=$(echo $2 |cut -f1 -d'/') #Station ID
> gtsnpSID1=$(echo $gtsnpSID |cut -c1) #Station ID first character
> gtsnpYMDHMS=$(echo $2 |cut -f2 -d'/') #Timestamp
> 
> if ([ $gtsnpSID1 != "R" ] && [ $gtsnpRAD -eq 1 ]) || ([ $gtsnpSID1 ==
> "R" ] && [ $gtsnpRAD -eq 0 ]);then
> if [ -s $gtsnpFN ];then
> rm $gtsnpFN 1>>$gtsnpLOGFN 2>&1
> echo "$(basename $0): Removed: $1 $2 RAD: $gtsnpRAD $(date
> '+%H:%M:%S')" >> $gtsnpLOGFN
> fi
> elif [ $gtsnpRAD -gt 1 ] && [ ! -s $gtsnpFN ];then
> gtsnpFN=/dev/null
> echo "$(basename $0): No Begining: $1 $2 RAD: $gtsnpRAD $(date
> '+%H:%M:%S')" >> $gtsnpLOGFN
> fi
> 
> nexradII -v -l $gtsnpLOGFN $gtsnpFN 1>>$gtsnpLOGFN 2>&1
> if [ $? -ge 0 ];then
> if [ $gtsnpEND = 'E' ];then
> nohup gtsnp_nr2comp $gtsnpSHM $1 1>>$gtsnpLOGFN 2>&1 &
> fi
> else
> echo "$(basename $0): bunzip failed $2 $(date '+%H:%M:%S')" >> $gtsnpLOGFN
> fi

Do the gtsnp_nr2decomp(1) log files in /proc_sm/gtsnp/logs indicate
anything amiss (e.g., "No Begining")?

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: LJY-425624
Department: Support LDM
Priority: Normal
Status: On Hold