Re: [ldm-users] cnvgrib Utility Help

So grib2 file looks OK. Something wrong with cnvgrib. As I said before, I have had problems with cnvgrib in the past. If I recall correctly it had to do with default integer sizes 4 vs 8 bytes. What version of operating system are you using?

On 20/04/16 12:11 AM, Michelle Serino wrote:
Sorry about that. On the .grb2 file, I get: 492053148 21637412 ruc2anl_130_20090605_2200_000.grb2.

Thanks, too, for the cksum info.

Michelle M. Serino
M.S. Candidate
Texas A&M University
Atmospheric Sciences Dept.
Eller O&M, Suite 1017
College Station, TX 77843
(484) 769-0949

On Tue, Apr 19, 2016 at 7:10 PM, George Trojan - NOAA Federal <george.trojan@xxxxxxxx <mailto:george.trojan@xxxxxxxx>> wrote:

    By the way, I asked for checksum on the GRIB2 file. We know the
    converted one is too short.

    On Tue, Apr 19, 2016 at 11:07 PM, George Trojan - NOAA Federal
    <george.trojan@xxxxxxxx <mailto:george.trojan@xxxxxxxx>> wrote:

        Checksum value and file size. Google should be your friend:
        https://en.wikipedia.org/wiki/Cksum

        I did have in the past issues with cnvgrib built on Centos 6
        and recent Fedora's. Before going into this, let's eliminate
        simple causes.

        On Tue, Apr 19, 2016 at 10:53 PM, Michelle Serino
        <mmserino@xxxxxxxx <mailto:mmserino@xxxxxxxx>> wrote:

            I get:

            942363691 228074 ruc2anl_130_20090605_2200_000.grb.


            What do those numbers represent?  I am not familiar with
            the cksum command.


            Michelle M. Serino
            M.S. Candidate
            Texas A&M University
            Atmospheric Sciences Dept.
            Eller O&M, Suite 1017
            College Station, TX 77843
            (484) 769-0949 <tel:%28484%29%20769-0949>

            On Tue, Apr 19, 2016 at 6:49 PM, George Trojan - NOAA
            Federal <george.trojan@xxxxxxxx
            <mailto:george.trojan@xxxxxxxx>> wrote:

                Either the input file is corrupted, or your version of
                cnvgrib is bad. Try this to eliminate the first
                possibility:

                $ cksum ruc2anl_130_20090605_2200_000.grb2
                492053148 21637412 ruc2anl_130_20090605_2200_000.grb2

                The numbers 492053148 21637412 should be the same.

                On Tue, Apr 19, 2016 at 10:42 PM, Michelle Serino
                <mmserino@xxxxxxxx <mailto:mmserino@xxxxxxxx>> wrote:

                    When I do 'wgrib
                    ruc2anl_130_20090605_2200_000.grb,'I
                    
get,'1:0:d=09060522:HGT:kpds5=7:kpds6=100:kpds7=1000:TR=1:P1=0:P2=0:TimeU=1:1000
                    mb:anl:NAve=0,'and that is the only output. I am
                    not sure exactly how to read that output and if
                    that indicates that there is only one field.

                    I got the length of the .grb file as only 228074
                    bytes: -rwxr-xr-x 1 mserino 30490 228074 Apr  7
                    17:39 ruc2anl_130_20090605_2200_000.grb

                    Michelle M. Serino
                    M.S. Candidate
                    Texas A&M University
                    Atmospheric Sciences Dept.
                    Eller O&M, Suite 1017
                    College Station, TX 77843
                    (484) 769-0949 <tel:%28484%29%20769-0949>

                    On Tue, Apr 19, 2016 at 6:00 PM, George Trojan -
                    NOAA Federal <george.trojan@xxxxxxxx
                    <mailto:george.trojan@xxxxxxxx>> wrote:

                        Does wgrib list only one field? I just ran
                        convert on the same file. There should be 317
                        data fields. What is the length of .grb file?
                        I got 65403248 bytes.

                        George

                        On Tue, Apr 19, 2016 at 9:31 PM, Michelle
                        Serino <mmserino@xxxxxxxx
                        <mailto:mmserino@xxxxxxxx>> wrote:

                            Thank you everyone for getting back to me.

                            My apologies for not including the
                            location of my data.  I downloaded it from
                            http://nomads.ncdc.noaa.gov/data/rucanl/ for
                            the appropriate date and time.  Let me
                            respond to everyone's suggestions.

                            1.  When I run:

                            od -c ruc2anl_130_20090605_2200_000.grb | less

                            I get output:

                            0000000 051107 041111 075003 000752 000000
                            001034 064407 100202

                            0000020 062007 164003 003011 013005 000400
                            000000 000001 000000

                            0000040 000025 000400 000000 000052 001777
                            141401 050401 037400

                            0000060 100631 135354 100410 014163 032000
                            000351 164464 040000, etc.


                            2. When I run:


                            wgrib ruc2anl_130_20090605_2200_000.grb


                            I get output:


                            
1:0:d=09060522:HGT:kpds5=7:kpds6=100:kpds7=1000:TR=1:P1=0:P2=0:TimeU=1:1000
                            mb:anl:NAve=0


                            3.  When I run:

                            wgrib -v ruc2anl_130_20090605_2200_000.grb


                            I get similar output:


                            1:0:D=2009060522:HGT:1000
                            mb:kpds=7,100,1000:anl:winds in grid
                            direction:"Geopotential height [gpm]


                            4.  George, you mentioned that "It is
                            possible that the program does not know
                            about GRIB2 fields, specific to the office
                            that created the file."  By program, are
                            you referring to the program I am using to
                            process these data?  Or are you referring
                            to another program?  I am not able to test
                            the wgrib2 command at the moment because I
                            do not have the permissions to install it
                            (my advisor will have to do that).


                            It appears that wgrib at least recognizes
                            the *.grb file. Are the lists of the grids
                            as they should be?  Perhaps something
                            small is getting lost in the conversion
                            process that my processing code (using
                            Warning Decision Support System -
                            Integrated Information algorithms) cannot
                            reconcile?


                            Thank you for the continued help!

                            Michelle

                            Michelle M. Serino
                            M.S. Candidate
                            Texas A&M University
                            Atmospheric Sciences Dept.
                            Eller O&M, Suite 1017
                            College Station, TX 77843
                            (484) 769-0949 <tel:%28484%29%20769-0949>

                            On Mon, Apr 18, 2016 at 1:52 AM, Michael
                            Dross <mdross@xxxxxxxxxxxxxxxxxx
                            <mailto:mdross@xxxxxxxxxxxxxxxxxx>> wrote:

                                If you have wgrib installed do a

                                 wgrib -v
                                ruc2anl_130_20090605_2200_000.grb


                                If it converted it correctly you
                                should get a listing of the grids. If
                                not,  something is amiss with the
                                cnvgrib you have.

                                - Mike


                                Sent from my iPad

                                On Apr 17, 2016, at 9:11 PM, Michelle
                                Serino <mmserino@xxxxxxxx
                                <mailto:mmserino@xxxxxxxx>> wrote:

                                Hi all,

                                I am using NCAR's cnvgrib utility to
                                convert grib2 RUC-Analysis data to
                                grib1.  An example of one of these
                                data files is below:

                                ruc2anl_130_20090605_2200_000.grb2

                                When I run the command,

                                cnvgrib
                                -g21 ruc2anl_130_20090605_2200_000.grb2 
ruc2anl_130_20090605_2200_000.grb


                                the converting process seems to
                                work.  I get a file with an extension
                                of "grb."  However, while the file
                                type is listed as a data file, it
                                appears green, as an executable
                                file.  In addition, the code I am
                                using does not recognize the file as
                                a grb1 file.  (The code only
                                recognizes grb1 files.)  The website
                                to which I referred to use this
                                utility
                                (http://blog.nssl.noaa.gov/wdssii/)
                                did not list any additional options
                                to use besides the required '-g21.'
                                 Am I missing something? This is my
                                first implementation of the cnvgrib
                                utility, so I apologize if I have
                                made a naive mistake.  I appreciate
                                any help.

                                Best regards,

                                Michelle Serino

                                Michelle M. Serino
                                M.S. Candidate
                                Texas A&M University
                                Atmospheric Sciences Dept.
                                Eller O&M, Suite 1017
                                College Station, TX 77843
                                (484) 769-0949
                                <tel:%28484%29%20769-0949>
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