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On Wed, 20 Oct 2004, Dan Swank wrote: > I copied the narr.cdl file from the FTP and tried: > > gribtonc -v -l ./log -e ./error ./narr.cdl > narr-b_221_20010101_0000_000.nc < narr-b_221_20010101_0000_000.grb > here's the process # creates cdl file narr.cdl % gribtocdl -v narr-b_221_20010101_0000_000.grb > narr.cdl # creates netcdf file narr.nc in verbose mode, logging to screen % gribtonc -vl - narr.cdl narr.nc < narr-b_221_20010101_0000_000.grb > Result > Segmentation fault explained below, set UDUNITS_PATH > and > Oct 20 19:31:05 gribtonc[32594]: Starting Up > in the ./log file. > > Any idea whats going on? It is likely gribtonc (or more likely one of > its dependancies) is not installed correctly on our system (RedHat 7.3) > Also, what did you use to create this CDL file? The data in cdl seems > like a translation of the information in the grib PDS, reworked into a > format that ncgen can understand. > Any way i can get anymore debug information regarding this? > > Only hunch is that it is not happy with the udunits package > > -> /usr/local/udunits-1.11.7/udunits-1.11.7/bin/udunits > udunits(3): Couldn't open units database "/upc/udunits/etc/udunits.dat": ahh, that's the problem. udunits can't find udunits.dat either place udunits.dat in dir /upc/udunits/etc/ or set environment var % setenv UDUNITS_PATH /your/udunits/path/udunits.dat replace /your/udunits/path/ with appropriate path robb... > No such file or directory > Segmentation fault > > But, while building the unidata decoders package it only seemed to want > the .dat .a and .h files within these packages. > Would this be the source of the problems? > > -Dan > > > > Robb Kambic wrote: > > >Thanks russ for the clarification. i was assuming you were familar with > >the decoders process. if i can answer any more questions let me know. i'll > >try to be more descriptive. > > > >robb... > > > > > >On Tue, 19 Oct 2004, Dan Swank wrote: > > > > > > > >>Russ > >> > >>Actually, i was, at first, trying > >>GRIB -( gribtocdl )-> CDL -( gribtonc )-> NetCDF > >>Which i now understand is completely wrong, thanks for the help. > >>As you have noticed, we are completely unfamiliar with these programs. > >> > >>Attempting it the correct way now, i'll let you know how it goes. > >> > >>-Dan > >> > >> > >> > >>Russ Rew wrote: > >> > >> > >> > >>>Robb, > >>> > >>> > >>> > >>> > >>> > >>>>i downloaded the file from the last message, created a cdl, and decoded > >>>>the grb file. there might be something wrong with Dan's decoders build or > >>>>it could be a platform issue. this was done on a solaris box 5.9 The > >>>>narr.cdl file is attached and the files narr.cdl, narr.grb, and narr.nc > >>>>are > >>>>in the Unidata's ftp dir at > >>>> > >>>>ftp unidata.ucar.edu > >>>> > >>>>% cd pub/contrib > >>>>% mget narr* > >>>> > >>>> > >>>> > >>>> > >>>Thanks Robb. The file sizes are: > >>> > >>> -rw-rw-r-- 1 rkambic ustaff 3486764 Oct 19 13:32 narr.nc > >>> -rw-rw-r-- 1 rkambic ustaff 8560 Oct 19 13:32 narr.cdl > >>> -rw-rw-r-- 1 rkambic ustaff 1398914 Oct 19 13:32 narr.grb > >>> > >>>so the netCDF file is about 2.5 times as big as the GRIB file. > >>> > >>>I'm guessing the source of the problem may come from using > >>> > >>> GRIB -> (via gribtocdl) -> CDL -> (via ncgen) -> netCDF > >>> > >>>(Using gribtocdl to generate a very large CDL file and then using ncgen > >>>to convert that into a netCDF file.) > >>> > >>>I think Robb used the following tools instead: > >>> > >>> GRIB -> (via gribtocdl) -> CDL > >>> GRIB and CDL -> (via gribtonc) -> netCDF > >>> > >>>(Using gribtocdl to generate a small CDL file describing structure of > >>>the desired netCDF file and then using gribtonc to convert the GRIB > >>>data into the netCDF file.) > >>> > >>>--Russ > >>> > >>> > >>> > >>> > >>-- > >>Dan Swank <address@hidden> > >>NOMADS programmer > >>STG, Incorporated - Government Contractor > >>151 Patton Avenue, Room 514 > >>Asheville, NC 28801 > >>Phone: 828-271-4007 > >> > >> > >> > >> > > > >=============================================================================== > >Robb Kambic Unidata Program Center > >Software Engineer III Univ. Corp for Atmospheric > >Research > >address@hidden WWW: http://www.unidata.ucar.edu/ > >=============================================================================== > > > > > > -- > Dan Swank <address@hidden> > NOMADS programmer > STG, Incorporated - Government Contractor > 151 Patton Avenue, Room 514 > Asheville, NC 28801 > Phone: 828-271-4007 > > =============================================================================== Robb Kambic Unidata Program Center Software Engineer III Univ. Corp for Atmospheric Research address@hidden WWW: http://www.unidata.ucar.edu/ ===============================================================================