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Re: xml representation of TDS dataset contents



Ben Domenico wrote:

Thanks, John,
I'm trying access one variable for all its forecast hours and then perform some arcGIS data analysis operations for each of the forecast hours in order to create an animation in arcMap. I suppose I could ask for all the forecast hours, but then, I'd have to figure out how many forecast hours are in the file once I get it on my local machine. 

since you get back a netcdf file, that should be easy enough.
The WCS getCapabilities does not seem to return any information about forecast times. I guess it's time for me to learn the details of WCs describeCoverage. 

may be helpful:

http://motherlode.ucar.edu:8080/thredds/docs/WCS/index.html



Thanks again.

-- Ben
On 10/24/06, *John Caron* <address@hidden <mailto:address@hidden>> wrote: 

    Hi Ben:

    If you append "&wantXML" to the showForm URL, you get back the XML
    before its been XSL transformed to HTML, eg:

    
http://motherlode.ucar.edu:9080/thredds/ncServer/fmrc/NCEP/GFS/CONUS_80km/files/GFS_CONUS_80km_20061023_0600.grib1?showForm&wantXML
    
<http://motherlode.ucar.edu:9080/thredds/ncServer/fmrc/NCEP/GFS/CONUS_80km/files/GFS_CONUS_80km_20061023_0600.grib1?showForm&wantXML>

    unfortunately, the returned XML is an unpublished format, and may
    change in the future. ignore the vertCoord amd missing stuff, and
    you see its a list of the available variables and what forecast
    hours they are available at. The forecast hours do change for some
    models depending on the run time. This is a complication for
    operational models like NCEP.

    the XML returned by WCS is standardized but more complicated, eg:
http://motherlode.ucar.edu:9080/thredds/wcs/fmrc/NCEP/GFS/CONUS_80km/files/GFS_CONUS_80km_20061023_0600.grib1?request=GetCapabilities&version=1.0.0&service=WCS 
    
<http://motherlode.ucar.edu:9080/thredds/wcs/fmrc/NCEP/GFS/CONUS_80km/files/GFS_CONUS_80km_20061023_0600.grib1?request=GetCapabilities&version=1.0.0&service=WCS>

    we have a new "latest" dataset that should be useful. What problem
    are you trying to solve with knowing the available forecast hours?

    Ben Domenico wrote:
     > Hi,
     >
     > As many of you know, I've been working on scripts to automate the
     > delivery and processing of subsets of datasets from TDS sites.  I've
     > managed to make this work for a few of the model output datasets
    (NAM,
     > RUC on motherloade, WRF on lead4).  However, it is clear that the
     > approach I'm using -- basically scraping the HTML of the netCDFserver
     > form for selecting variables, bounding  boxes and forecast times --
     > presents problems because the HTML is very different for different
     > models.  In some cases, it actually seems to change from time to time
     > even for the same model.  Robb has mentioned XML documents that
    contain
     > much of the same information in a more systematic and/or consistent
     > format.  I think that would be a better approach.  Maybe the WCS
     > interactions might be a better approach.
     >
     > An example of the difficulties that arise is the fact that different
     > variables have different forecast times and the lists appear in a
     > variety of different ways in the netCDFserver forms for different
    models.
     >
     > Please send me whatever suggestions you have for the best way to
    proceed.
     >
     > Thanks.
     >
     > -- Ben
     >
     > PS I realize this is probably not the best time to be distracting you
     > from the training workshop but I thought I'd mention it while it is
     > fresh in my mind.