Thanks, I'm embarrassed to say gradsdap was my problem! The icon setup on
the desktop here opened "grads.exe" rather than gradsdap. Not much of an
excuse and definitely enough for me to feel pretty daft.
So now I can see individual timesteps, I'll have a play with template
option in descriptor file to access the different timesteps.
Thanks
On Mon, 12 Jan 2009 07:32:34 -0500, Jennifer Adams <jma at COLA.IGES.ORG>
wrote:
>You should be using the 'gradsdap' executable to access OPeNDAP
>servers. I am able to open one of these data sets with sdfopen. Beware
>that there are many more coordinate variables than the usual set, and
>to see all the variables you will need to use xdfopen or open with a
>descriptor file to map the following to X, Y, Z, T, and E:
>
>netcdf gfs_4_20090109_1800_171 { // format variant: 64bit
>dimensions:
> time1 = 1 ;
> pressure1 = 1 ;
> lat = 361 ;
> lon = 720 ;
> pressure = 26 ;
> time = 1 ;
> pressure3 = 21 ;
> pressure_difference_layer1 = 1 ;
> pressure4 = 2 ;
> potential_vorticity_surface = 2 ;
> height_above_ground1 = 1 ;
> pressure2 = 6 ;
> pressure_difference_layer = 1 ;
> depth_below_surface_layer = 4 ;
> altitude_above_msl = 3 ;
> height_above_ground = 1 ;
> bounds_dim = 2 ;
>
>
>On Jan 11, 2009, at 5:59 AM, James Burn wrote:
>
>> Hi
>>
>> I'm wondering if it is possible to use Grads 2.0 to access data via an
>> Opendap server such as
>> http://nomads.ncdc.noaa.gov/thredds/catalog/gfs4/catalog.html
>>
>> I've not seen any mention of Thredds here on the Grads list so am
>> guessing
>> its not the done thing. I've Windows XP here and Opensuse Linux at
>> home.
>>
>> When I try to sdfopen one of the Grib2 files eg
>>
http://nomads.ncdc.noaa.gov/thredds/dodsC/gfs4/200901/20090108/gfs_4_2009010
>> 8_1800_171.grb2
>>
>> I get gaopnc error and "Can't ingest SDF Metadata".
>>
>> I've also tried making the appropriate .inv and .idx files locally and
>> opening a local .ctl file which seems more promising, but seems to
>> fall
>> over when accessing the binary file via http.
>>
>> Is what I am trying to do possible? Or is data access limited to
>> dods and
>> local servers? My feeling is that I'm missing a trick or two.
>>
>> This is my first post, although I've been hacking together scripts
>> for a
>> year now and would like to thank all those who contribute to this
>> list for
>> the tips I've picked up so far!
>>
>> Thanks
>> James Burn
>
>--
>Jennifer M. Adams
>IGES/COLA
>4041 Powder Mill Road, Suite 302
>Calverton, MD 20705
>jma at cola.iges.org
>
>
>
>