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[THREDDS #GJF-200148]: TDS 4.3 GRIB names different from TDS 4.2



Fan,

I was out of town for a few days, but I'll get my head into your issue again 
today and let you know what I find.

-Lansing

> Hello Lansing,
> 
> Any comments/findings about my questions?
> 
> With or without featureCollection we need to serve grib data in their granule 
> form, so how to make grib table work for individual granules is remaining 
> question number one.  So far our grib table works with aggregated 
> featureCollection dataset, but not for granules under 'files' folder.  I also 
> tried the 'iospParam' attribute of the 'netcdf' element outside 
> featureCollection, like
> 
> <datasetScan name="GLDAS_CLM10SUBP_3H" ID="GLDAS_CLM10SUBP_3H" 
> path="GLDAS_CLM10SUBP_3H" location="/ftp/data/s4pa_TS2/GLDAS_CLM10SUBP_3H/">
> <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2"; 
> iospParam="gribParameterTable=/home/ffang/gribtab_clm.tab">
> </netcdf>
> ...
> 
> and TDS didn't seem to read the grib table.
> 
> The other main question is about the collection .ncx file usage.  I found 
> accessing that file very speedy in TDS and wonder if it should be used to 
> serve our extremely long time series datasets (~30 years of hourly data), 
> i.e. shall we let TDS make the file at the data location instead of under 
> cache/cdm, and treat it as the timeseries dataset?
> 
> -Fan
> 
> ________________________________________
> From: Fang, Fan (GSFC-610.2)[ADNET SYSTEMS INC]
> Sent: Friday, May 17, 2013 2:50 PM
> To: Fang, Fan (GSFC-610.2)[ADNET SYSTEMS INC]; address@hidden
> Cc: address@hidden
> Subject: RE: [THREDDS #GJF-200148]: TDS 4.3 GRIB names different from TDS 4.2
> 
> I take it back - the .tab extension apparently works.  We previously made an 
> error renaming the grib table.
> 
> I also changed '/s' to '.s' but both came out the same.  For example, 
> kg/m^2/s or kg/m^2.s would show up as kgm^2s, which is wrong.  I suppose we 
> have to change it to kgm^-2s^-1 in the table?  I hope it is consistent with 
> software like 'wgrib'.
> 
> It seems the variable names are essentially the long names and units in grib 
> table plus something like '_surface', with space chars replaced by 
> underscores.  I guess we can survive with that.
> 
> These show up in the collection 'Best Timeseries' (is there a way to 
> re-configure this collection name?), but not for individual files under 
> 'files' folder in TDS (again, is there a way to configure for the folder 
> name?).  Is this expected?
> 
> One final question: if I drop the collection index file .ncx at the data 
> location, TDS seems to be able to serve it like a dataset, and for time 
> series it is surprisingly fast to serve the .ncx file instead.  Is this 
> intended - in other words we shall direct user to use .ncx, especially for 
> long time series?  I know in default it's under cache/cdm and not exposed to 
> users.  What's the catch here?
> 
> Thanks.
> 
> -Fan
> ________________________________________
> From: Fang, Fan (GSFC-610.2)[ADNET SYSTEMS INC]
> Sent: Thursday, May 16, 2013 6:13 PM
> To: address@hidden for
> Cc: address@hidden
> Subject: RE: [THREDDS #GJF-200148]: TDS 4.3 GRIB names different from TDS 4.2
> 
> I can confirm changing the grib table name to have .tab as extension still 
> does not work.
> 
> I'll try the modifications in the units, but wonder why it fails for all 
> since some of them have legit units, like 'K' for temperature.
> 
> -Fan
> ________________________________________
> From: Unidata THREDDS Support [address@hidden]
> Sent: Thursday, May 16, 2013 2:37 PM
> To: Fang, Fan (GSFC-610.2)[ADNET SYSTEMS INC]
> Cc: address@hidden; Fang, Fan (GSFC-610.2)[ADNET SYSTEMS INC]; address@hidden
> Subject: [THREDDS #GJF-200148]: TDS 4.3 GRIB names different from TDS 4.2
> 
> Fan,
> 
> I did a little more digging, and I don't think the file name extension will 
> matter - that was my misinterpretation of how the table was getting picked 
> up.  However, you will probably have the best result directly embedding the 
> table information in your featureCollection element using the xml notation.  
> It looks like you tried this already, so I am not sure why it did not work 
> for you.  It is possible that it broke because you did not follow udunits 
> standard -- for instance, square meters is notated as m^2, rather than 
> m(superscript)2.  The code you are asking about is just the number that 
> identifies the grib parameter.
> 
> Inside your <featureCollection> element:
> 
> <gribConfig>
> <parameterMap>
> <parameter code="2">  <<-- This will override the standard table values for 
> parameter 2 (code < 128 are standard, > 128 are local)
> <description>Pressure reduced to MSL</description>
> <units>Pa</units>
> <name>PRMSL</name>
> </parameter>
> <parameter code="131">
> <description>Snowfall rate</description>
> <units>kg/m^2.s</units> <<--Compound units are notated with a dot, so /m^2/s 
> is just /m^2.s
> <name>Snof</name>
> </parameter>
> ...
> 
> </parameterMap>
> 
> </gribConfig>
> -Lansing Madry
> Unidata
> Boulder, Colorado
> 
> Ticket Details
> ===================
> Ticket ID: GJF-200148
> Department: Support THREDDS
> Priority: Low
> Status: Closed
> 
> 

-Lansing Madry
  Unidata
  Boulder, Colorado

Ticket Details
===================
Ticket ID: GJF-200148
Department: Support THREDDS
Priority: Low
Status: Open