[Met_help] met and conditional verification across variables

John Halley Gotway johnhg at ucar.edu
Mon Apr 12 13:05:38 MDT 2010


Mike,

I think it may be a problem with how you're calling PCP-Combine.  Listed below is the usage statement for PCP-Combine, when summing up files:

        SUM_ARGS:
                init_time
                in_accum
                valid_time
                out_accum
                out_file
                [-pcpdir path]
                [-pcprx reg_exp]

                where   "init_time" indicates the initialization time of the input Grib files in YYYYMMDD_HHMMSS format (required).
                        "in_accum" indicates the accumulation interval of the input Grib files in HH format (required).
                        "valid_time" indicates the desired valid time in YYYYMMDD_HHMMSS format (required).
                        "out_accum" indicates the desired accumulation interval for the output NetCDF file in HH format (required).
                        "out_file" indicates the name of the output NetCDF file to be written consisting of the sum of the accumulation intervals (required).
                        "-pcpdir path" overrides the default precipitation directory (/d1/johnhg/MET/MET_releases/METv2.0_patch/data/sample_obs/ST2ml) (optional).
                        "-pcprx reg_exp" overrides the default regular expression for precipitation file naming convention (.*) (optional).

And here's the command line you're running:
 pcp_combine -sum 00000000_000000 3 20100318_000000 168 -pcpdir <the dir> -pcprx *0p25

It looks like you've failed to list an output file name to be used in the correct place in the command line.  Try changing it something like:
 pcp_combine -sum 00000000_000000 3 20100318_000000 168 test_output.nc -pcpdir <the dir> -pcprx 0p25

Also notice that I've removed the '*' from the -pcprx argument.  Just using '0p25' should do what you want.  Otherwise, the shell will expand that '*' on the command line and you'll get unexpected
behavior.

Let me know if that helps.

Thanks,
John

Shaw, Michael J CTR USAF AFWA 16 WS/WXE wrote:
> Hi John.
> 
> Trying to accumulate precip of a bunch of agrmet grib files.  Here's what I get:
> 
> pcp_combine -sum 00000000_000000 3 20100318_000000 168 -pcpdir <the dir> -pcprx *0p25
> 
> [1]Reading input file:
> 
>    GribFile::open(const char *) -> unable to open grib file
> 
> While I look around for the culprit and fix, maybe you can help me before I get there.  Of course, these are the airforce grib files...
> 
> Thanks,
> Mike
> 
> -----Original Message-----
> From: John Halley Gotway [mailto:johnhg at ucar.edu] 
> Sent: Tuesday, March 23, 2010 1:14 PM
> To: Shaw, Michael J CTR USAF AFWA 16 WS/WXE; met_help
> Subject: Re: [Met_help] met and conditional verification across variables
> 
> Mike,
> 
> Great, thanks.  Please send me the changes when you get a chance, and I'll look into getting them incorporated into the next version of MET.
> 
> John
> 
> Shaw, Michael J CTR USAF AFWA 16 WS/WXE wrote:
>> Hi John.
>>
>> I think I was able to make the mods I needed and rebuild MET.  I'm out
>> of town for much of the week, but I can pass those on to you early next
>> week if you want.
>>
>> Thanks,
>> Mike
>>
>>
>> -----Original Message-----
>> From: John Halley Gotway [mailto:johnhg at rap.ucar.edu] 
>> Sent: Friday, March 19, 2010 10:23 PM
>> To: Shaw, Michael J CTR USAF AFWA 16 WS/WXE
>> Cc: met_help at ucar.edu
>> Subject: Re: [Met_help] met and conditional verification across
>> variables
>>
>> Mike,
>>
>> You may be able to do what you'd like to do using what we've called
>> "data
>> masking".  Listed below is an excerpt from the Point-Stat configuration
>> file describing the "mask_poly" option:
>>
>> //
>> // Specify a comma-separated list of masking regions to be applied.
>> // An empty list indicates that no additional masks should be used.
>> // The masking regions may be defined in one of 4 ways:
>> //
>> // (1) An ASCII file containing a lat/lon polygon.
>> //     Latitude in degrees north and longitude in degrees east.
>> //     By default, the first and last polygon points are connected.
>> //     e.g. "MET_BASE/data/poly/EAST.poly" which consists of n points:
>> //          "poly_name lat1 lon1 lat2 lon2... latn lonn"
>> //
>> // (2) The NetCDF output of the gen_poly_mask tool.
>> //
>> // (3) A NetCDF data file, followed by the name of the NetCDF variable
>> //     to be used, and optionally, a threshold to be applied to the
>> field.
>> //     e.g. "sample.nc var_name gt0.00"
>> //
>> // (4) A GRIB data file, followed by a description of the field
>> //     to be used, and optionally, a threshold to be applied to the
>> field.
>> //     e.g. "sample.grb APCP/A3 gt0.00"
>> //
>> // Any NetCDF or GRIB file used must have the same grid dimensions as
>> the
>> // data being verified.
>> //
>> // MET_BASE may be used in the path for the files above.
>> //
>> // e.g. mask_poly[] = [ "MET_BASE/data/poly/EAST.poly",
>> //                      "poly_mask.ncf",
>> //                      "sample.nc APCP",
>> //                      "sample.grb HGT/Z0 gt100.0" ];
>> //
>> mask_poly[] = [ "MET_BASE/data/poly/EAST.poly" ];
>>
>> Option (4) listed above may do what you'd like.  You'd need the land use
>> field on the same grid as the data you're verifying.  Basically, you'd
>> specify the GRIB file you'd like to use, the field you want (land use in
>> your case), and then the threshold you'd like applied to that field -
>> and
>> you could specify that threshold as "eq0" or "eq1" - or whatever the
>> land
>> use values are.  That threshold defines the data mask that's applied to
>> the data.  You may specify as many of those masking regions as you'd
>> like
>> - probably one per land use category you'd like to verify.
>>
>> Hope that helps.
>>
>> John Halley Gotway
>>
>>
>>> Hi.
>>>
>>>
>>>
>>> I'm interested in verifying conditionally;
>> if(landuse==suchandsuch)then
>>> "how does surface temperature verify across cases and against
>>> observations/retrievals?" kind of thing.  Basically, doing what MET
>> does
>>> with thresholds, but applying the threshold to other variables
>> (preferably
>>> multiple - if(x<landuse<y)elseif(y<landuse<z) for instance) with a
>> grib
>>> file, e.g..  Not finding that in MET: Am I missing something or is
>> that
>>> something that's planned for a (near-)future release?
>>>
>>>
>>>
>>> Thanks,
>>>
>>> Mike
>>>
>>>
>>>
>>> ______________________________________________
>>>
>>> Michael Shaw, Contractor
>>>
>>> SAIC/NASA Support Scientist
>>>
>>> michael.shaw.ctr at offutt.af.mil
>>>
>>> 16WS Environmental Characterization
>>>
>>> HQ AFWA-SAIC
>>>
>>> 101 Nelson Drive
>>>
>>> Offutt AFB, NE 68113-1023
>>>
>>> 402-232-7690 Comm * 402-272-7690 DSN * 402-294-8230 Fax
>>>
>>>
>>>
>>> _______________________________________________
>>> Met_help mailing list
>>> Met_help at mailman.ucar.edu
>>> http://mailman.ucar.edu/mailman/listinfo/met_help
>>>


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