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Dongyu, The paths in pqact.conf are relative to the ~ldm account directory. The sample GEMPAK decoder entries I provide at: http://www.unidata.ucar.edu/packages/gempak/tutorial/pqact/decoders.tbl show the use of decoders/dc..... for the executable path. You can either create a link from your $GEMEXE directory to ~ldm/decoders (so that a ~ldm/decoders/dcuair finds your $GEMEXE/dcuair file), or create a decoders directory under ~ldm and copy the $GEMEXE/dc* programs into ~ldm/decoders. In your pqact.conf lines below, you have /decoders/dcuair and /usr/local/ldm/decoders/dcmetr. These are likely wrong. If you create the ~ldm/deciders directory as I mentioned above, then the proper executable paths will be decoders/dcuair and decoders/dcmetr. Or, you can give the full path to your programs (but it makes for more editing of the samples I provide): /export/home/gempack/bin/sol/dcuair /export/home/gempack/bin/sol/dcmetr. Also, you do not need to but TAB characters between the decoder options and there values, eg, <TAB> characters separate the arguments interpreted by pqact: #upperair data DDS|IDS <TAB> ^U[ABDEFGHIJKLMPQRSTXZ].... .... ([0-3][0-9])([0-2][0-9]) <TAB> PIPE <TAB> /decoders/dcuair -b 24 -m 16 <TAB> -d /usr/local/ldm/data/gempak/logs/dcuair.log <TAB> -e GEMTBL=/export/home/gempack/gempak/tables/stns <TAB> -s snstns.tbl <TAB> data/gempak/upperair/YYYYMMDD_upa.gem For GRIB data, use the dcgrib2 example I provide in the web URL above: # Global GRIB decoding action. # Products stored maintained in $GEMTBL/grid/gribkey.tbl HDS ^[HOYZ].* PIPE decoders/dcgrib2 -d data/gempak/logs/dcgrib.log -e GEMTBL=/export/home/gempack/gempak/tables You can use GARP, or NMAP2 as GUI interfaces to display the data. Or, the command line programs like sfmap, snmap, etc. The configuration files in $GEMTBL/config/datatype.tbl and $GARPHOME/config/Garp_defaults.tbl all assume you use the decoded file locations under ~ldm/data/gempak as shown on the URL above. If you use these locations, then you only need to edit the environmental variable locations in $NAWIPS/Gemenviron for $GEMDATA on your system. For example, if your ~ldm account is /usr/local/ldm, and your data is being filed under the ~ldm/data/gempak directory, then set GEMDATA in the Gemenviron file to /usr/local/ldm/data/gempak. The decoders that come from NCEP (like dcmetr and dcuair) require that you create the data directory that they will write to, so make sure ~ldm/data/gempak/upperair and ~ldm/data/gempak/surface exist. The dcgrib2 decoder will create all the necessary directories. Steve Chiswell Unidata User Support >From: <address@hidden> >Organization: UCAR/Unidata >Keywords: 200204252028.g3PKSEa13166 >Dear Steve: > Thank you for your advice! > I have settled the problem according to your advice. I am a new comer >to LDM and UniDATA. I have the following questions: > >(1) How can I display the WMO and GRIB file using the GARP? > >(2)Is GARP the most common used software in GEMPAK to display data? > >(3)Now I want to receive the upper air data and surface data. So I >wrote following in my pqact.conf file. But I can't receive any data of >gem file. Can you tell me why? In addition ,Could I know which data I >am writing on my disk instead of "ldmadmin watch"? As you know, >ldmadmin watch only watch all the data I can receive , not the data I >wrote to my disk. I check my pqact.conf file to be syntax-correct.Thank >you very much. > > #upperair data >DDS|IDS ^U[ABDEFGHIJKLMPQRSTXZ].... .... ([0-3][0-9])([0-2][0-9]) > PIPE /decoders/dcuair -b 24 -m 16 > -d /usr/local/ldm/data/gempak/logs/dcuair.log > -e GEMTBL=/export/home/gempack/gempak/tables/stns > -s snstns.tbl > /usr/local/ldm/data/gempak/upperair/YYYYMMDD_upa.gem > >#surface data >DDS|IDS ^S[AP].* .... ([0-3][0-9])([0-2][0-9]) > PIPE /usr/local/ldm/decoders/dcmetr -b 9 -m >72 > -d /data/gempak/logs/dcmetr.log > -e GEMTBL=/export/home/gempack/gempak/tables/stns > -s sfmetar_sa.tbl > /usr/local/ldm/data/gempak/surface/YYYYMMDD_sao.gem > > >Dongyu Liu >----- Original Message ----- >From: Unidata Support <address@hidden> >Date: Thursday, April 25, 2002 10:47 am >Subject: 20020424: 20020424: Gempak installation! > > >