[ncarg-talk] ncarg-talk Digest, Vol 123, Issue 5

Sébastien POITEVIN sebastien.poitevin at meteoconsult.com
Fri Jan 12 08:07:41 MST 2018


Hi Mary,

Indeed, it's very strange. It may be when UNIPOST had created grib files
from netcdf files. I'm going to investigate.

2018-01-12 15:53 GMT+01:00 Mary Haley <haley at ucar.edu>:

> Hi Sébastien,
>
> Dave looked at this file with wgrib, and pointed out that there are two
> records that both have the same exact metadata.
>
> One record has only fill values and zeros. The other record has fill
> values, zeros and ones. NCL has no way to tell the difference, but
> apparently it is now choosing the other record from what the earlier
> versions of NCL did.
>
> Apparently it is undefined as to how it should behave if you have two
> records and nothing to distinguish them. Do you know anything about why
> this file has two records like this?
>
> --Mary
>
>
> On Fri, Jan 12, 2018 at 4:58 AM, Sébastien POITEVIN <sebastien.poitevin@
> meteoconsult.com> wrote:
>
>> Thanks for your help Mary.
>>
>> Indeed, we dont have the same problem with GFS grib files for example.
>>
>> Sent grib file has been produced by WRF-NMM (version V3.7.1) and UPPV3.0.
>>
>>
>>
>> 2018-01-11 18:58 GMT+01:00 <ncarg-talk-request at ucar.edu>:
>>
>>> Send ncarg-talk mailing list submissions to
>>>         ncarg-talk at ucar.edu
>>>
>>> To subscribe or unsubscribe via the World Wide Web, visit
>>>         http://mailman.ucar.edu/mailman/listinfo/ncarg-talk
>>> or, via email, send a message with subject or body 'help' to
>>>         ncarg-talk-request at ucar.edu
>>>
>>> You can reach the person managing the list at
>>>         ncarg-talk-owner at ucar.edu
>>>
>>> When replying, please edit your Subject line so it is more specific
>>> than "Re: Contents of ncarg-talk digest..."
>>>
>>>
>>> Today's Topics:
>>>
>>>    1. Re: [6.4.0 version] Bug : Categorical Snow always null
>>>       (Mary Haley)
>>>
>>>
>>> ----------------------------------------------------------------------
>>>
>>> Message: 1
>>> Date: Thu, 11 Jan 2018 11:58:28 -0600
>>> From: Mary Haley <haley at ucar.edu>
>>> To: S?bastien POITEVIN <sebastien.poitevin at meteoconsult.com>
>>> Cc: Ncl-talk <ncl-talk at ucar.edu>, ncarg-talk <ncarg-talk at ucar.edu>
>>> Subject: Re: [ncarg-talk] [6.4.0 version] Bug : Categorical Snow
>>>         always null
>>> Message-ID:
>>>         <CACNN_CLdCKu4bVbMeOHdxFsWzW+dJ7zK2HpWAKpsthQt2cSsVQ at mail.gm
>>> ail.com>
>>> Content-Type: text/plain; charset="utf-8"
>>>
>>> S?bastien,
>>>
>>> We downloaded some similar files from:
>>>
>>> https://nomads.ncdc.noaa.gov/data/meso-eta-hi/
>>>
>>> and didn't see any issues with them, using both older and current
>>> versions
>>> of NCL.
>>>
>>> Can you tell us what the source of this file is? I'm wondering if it's
>>> possibly a "non-standard" GRIB file (I realize there are no GRIB
>>> standards
>>> really, but some files do violate particular rules).
>>>
>>> --Mary
>>>
>>>
>>> On Thu, Jan 11, 2018 at 9:51 AM, Mary Haley <haley at ucar.edu> wrote:
>>>
>>> > Hi S?bastien,
>>> >
>>> > Sorry I didn't respond sooner.  I was at a conference.
>>> >
>>> > Thanks for providing a small file that clearly shows the problem.
>>> >
>>> > I have submitted a ticket on this, NCL-2712, and put a high priority
>>> on it.
>>> >
>>> > You are correct that it appears to be setting all the 1s to 0s. This is
>>> > very puzzling. I will see if we can look at this soon.
>>> >
>>> > --Mary
>>> >
>>> >
>>> >
>>> > On Tue, Jan 9, 2018 at 4:24 AM, S?bastien POITEVIN <sebastien.poitevin@
>>> > meteoconsult.com> wrote:
>>> >
>>> >> Dear Mary,
>>> >>
>>> >> Thanks for your help.
>>> >>
>>> >>  Find in attached, WRF-NMM grib file and, below, asked informations :
>>> >>
>>> >>
>>> >>
>>> >>    1. No error return with ncl_filedump
>>> >>    2.
>>> >>
>>> >>
>>> >> *printVarSummary(csnow) : Variable: csnowType: floatTotal Size:
>>> 1443112
>>> >>    bytes            360778 valuesNumber of Dimensions: 2Dimensions
>>> and sizes:
>>> >>     [g0_lat_0 | 529] x [g0_lon_1 | 682]Coordinates:
>>> g0_lat_0:
>>> >>    [53.012..39.787]            g0_lon_1: [-6.01..11.722]Number Of
>>> Attributes:
>>> >>    12  center :      US National Weather Service - NCEP (WMC)
>>> long_name :
>>> >>     Categorical snow  units :       yes=1;no=0  _FillValue :  1e+20
>>> >>    level_indicator :     1  gds_grid_type :       0
>>> parameter_table_version
>>> >>    :     2  parameter_number :    143  model :       North Pacific
>>> Hurricane
>>> >>    Wave Model  forecast_time :       18  forecast_time_units : hours
>>> >>    initial_time :        01/08/2018 (18:00) *
>>> >>    3.
>>> >> *printMinMax(csnow,0) *
>>> >>    (0)     Categorical snow: min=0   max=0
>>> >>
>>> >>    4.
>>> >>
>>> >>
>>> >> *print(num(ismissing(csnow))) (0)     61086 *
>>> >>
>>> >>
>>> >> 2018-01-08 17:16 GMT+01:00 Mary Haley <haley at ucar.edu>:
>>> >>
>>> >>> ?Dear Sebastien,
>>> >>>
>>> >>> In the future please post NCL questions / issues to
>>> ncl-talk at ucar.edu.
>>> >>> The ncarg-talk at ucar.edu email list is for NCAR Graphics users, and
>>> is
>>> >>> not an active group.
>>> >>>
>>> >>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>> >>>
>>> >>> ?Without having access to the dataset, it is hard for us to debug
>>> this
>>> >>> problem. It would help, then, if you could provide more information
>>> about
>>> >>> the variable, like what kind of metadata it has.
>>> >>>
>>> >>> Do you get any kind of error from ncl_filedump?
>>> >>>
>>> >>> Could you run the short NCL script below, and send me the output from
>>> >>> running it, using both NCL V6.3.0 and V6.4.0, including any error
>>> messages:
>>> >>>
>>> >>> a = addfile("20122017_15.grb","r")
>>> >>> csnow = a->CSNOW_GDS0_SFC
>>> >>> printVarSummary(csnow)
>>> >>> printMinMax(csnow,0)
>>> >>> print(num(ismissing(csnow)))
>>> >>>
>>> >>> Finally, is there some place we can download this file, or a similar
>>> >>> one,  from?
>>> >>>
>>> >>> Thanks,
>>> >>>
>>> >>> --Mary
>>> >>>
>>> >>> On Wed, Jan 3, 2018 at 1:49 AM, S?bastien POITEVIN <
>>> >>> sebastien.poitevin at meteoconsult.com> wrote:
>>> >>>
>>> >>>> Hi all,
>>> >>>>
>>> >>>> When we read "Categorical Snow" with NCL 6.4.0 version
>>> (ncl_filedump -v
>>> >>>> CSNOW_GDS0_SFC 20122017_15.grb or with 'PrintMinMax' command), we
>>> have
>>> >>>> always null value (min and max value = 0)  whereas we have no
>>> problem when
>>> >>>> we read the same grib file with the 6.3.0 version (min = 0 and max
>>> = 1).
>>> >>>>
>>> >>>> Grib files are produced by WRF-NMM (version V3.7.1) and UPPV3.0.
>>> >>>>
>>> >>>> Our system is "3.16.0-4-amd64 #1 SMP Debian 3.16.43-2+deb8u5
>>> >>>> (2017-09-19) x86_64 GNU/Linux"
>>> >>>>
>>> >>>> Unfortunately I cannot send you a WRF grib file because it is too
>>> large.
>>> >>>>
>>> >>>> Thanks for your help.
>>> >>>>
>>> >>>> --
>>> >>>>
>>> >>>> _______________________________________________
>>> >>>> ncarg-talk mailing list
>>> >>>> ncarg-talk at ucar.edu
>>> >>>> http://mailman.ucar.edu/mailman/listinfo/ncarg-talk
>>> >>>>
>>> >>>>
>>> >>>
>>> >>
>>> >>
>>> >> --
>>> >>
>>> >
>>> >
>>> -------------- next part --------------
>>> An HTML attachment was scrubbed...
>>> URL: <http://mailman.ucar.edu/pipermail/ncarg-talk/attachments/20
>>> 180111/d6b6bb63/attachment.html>
>>> -------------- next part --------------
>>> A non-text attachment was scrubbed...
>>> Name: signature3.jpg
>>> Type: image/jpeg
>>> Size: 27653 bytes
>>> Desc: not available
>>> URL: <http://mailman.ucar.edu/pipermail/ncarg-talk/attachments/20
>>> 180111/d6b6bb63/attachment.jpg>
>>>
>>> ------------------------------
>>>
>>> Subject: Digest Footer
>>>
>>> _______________________________________________
>>> ncarg-talk mailing list
>>> ncarg-talk at ucar.edu
>>> http://mailman.ucar.edu/mailman/listinfo/ncarg-talk
>>>
>>>
>>> ------------------------------
>>>
>>> End of ncarg-talk Digest, Vol 123, Issue 5
>>> ******************************************
>>>
>>
>>
>>
>> --
>>
>> _______________________________________________
>> ncarg-talk mailing list
>> ncarg-talk at ucar.edu
>> http://mailman.ucar.edu/mailman/listinfo/ncarg-talk
>>
>>
>


--
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ucar.edu/pipermail/ncarg-talk/attachments/20180112/57c4c881/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature3.jpg
Type: image/jpeg
Size: 27653 bytes
Desc: not available
URL: <http://mailman.ucar.edu/pipermail/ncarg-talk/attachments/20180112/57c4c881/attachment-0001.jpg>


More information about the ncarg-talk mailing list