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[Staging #FJY-535537]: Blended SST retrieve - Doubt
- Subject: [Staging #FJY-535537]: Blended SST retrieve - Doubt
- Date: Thu, 29 Jul 2010 06:48:05 -0600
You might try
http://code.google.com/p/nctoolbox/
for matlab opendap access.
John
> Hi Tom,
>
> Thank you very much for the instructions.
>
> I've tried to install a OPenDAP Matlab Client here, but I wasn't successful.
>
> We have Matlab version 2006a, and therefore I've tried to install loaddap
> version 3.6.1.
> But what happend is that I couldn't install the libdap-3.8.1 library
> (required by loaddap), and so wasn't able to proceed.
>
>
> Additionally, ncdump is not working here as you mentioned on the last
> message. Apparently, this is problem with our Internet connection.
>
> Anyway, ultimately I could download the data, using the parameters you gave
> me, in the ASCII format.
> We don't have a operational data retrieve system yet, but we are able to
> download the data using this approach.
>
> Again, Thank you very much for the attention.
>
>
> Best regards from Brazil
>
> 2010/7/27 Unidata THREDDS Support <address@hidden>
>
> > Hi Ricardo,
> >
> > re:
> > > This is the website I am trying to retrieve the data:
> > >
> > >
> > http://ourocean.jpl.nasa.gov:8080/thredds/dodsC/g1sst/sst_20100725.nc.html
> >
> > OK, thanks.
> >
> > There are two ways to do what you want:
> >
> > - install OPeNDAP client software that will allow you to programmatically
> > request the data. I just used the Unidata IDV to access the data off
> > of the OPeNDAP server you provided and was able to plot the SST values
> > and save the values plotted to a disk file.
> >
> > - specify the subset of the data manually through the web page you
> > reference
> > above.
> >
> > This approach will be more difficult since the control for selecting a
> > subdomain
> > for the data is in index space, not LatxLon space. The good news,
> > however, is
> > that the mapping from index space to LatxLon space appears
> > straightforward:
> >
> > Index Degrees
> > Longitude: 0..35999 -180..180
> > Latitude: 0..15999 -80..80
> >
> > So, there are 100 points per degree in both Latitude and Longitude.
> >
> > - you can download this data as a netcdf file using ncdump from the current
> > netcdf release (4.1.2)
> >
> > The following command would show how this file will look when accessed
> > thru ncdump:
> >
> > ncdump -h ncdump ncdump "
> > http://ourocean.jpl.nasa.gov:8080/thredds/dodsC/g1sst/sst_20100725.nc"
> >
> > This should produce the following output:
> >
> > netcdf sst_20100725 {
> > dimensions:
> > time = UNLIMITED ; // (1 currently)
> > lat = 16000 ;
> > lon = 36000 ;
> > variables:
> > float time(time) ;
> > time:unit = "hours since 1981-01-01 00:00:00" ;
> > float lon(lon) ;
> > lon:long_name = "longitude" ;
> > lon:standard_name = "longitude" ;
> > lon:axis = "X" ;
> > lon:units = "degrees_east" ;
> > float lat(lat) ;
> > lat:long_name = "latitude" ;
> > lat:standard_name = "latitude" ;
> > lat:axis = "Y" ;
> > lat:units = "degrees_north" ;
> > short SST(time, lat, lon) ;
> > SST:missingValue = -32768 ;
> > SST:add_offset = 273.15 ;
> > SST:scale_factor = 0.01 ;
> > SST:_FillValue = -32768s ;
> > byte data_days(lat, lon) ;
> > data_days:missingValue = -99s ;
> > data_days:_FillValue = -99b ;
> >
> > // global attributes:
> > :history = "Sun Sep 21 20:25:02 2008: ncatted -a
> > fillValue,SST,d,, global_1km_02_short.nc\n",
> > "Sun Sep 21 20:16:06 2008: ncatted -a
> > _FillValue,SST,c,s,-32768 global_1km_02_short.nc" ;
> > }
> >
> > We can access, say the variable SST within the specified bounding box by
> > defining a constraint expression:
> > ?SST[0:0][4000:8000][13000:15000]
> > Remember that the dimensions are zero-based, so if the arithmetic is
> > correct
> > the lat range [-40,0] should correspond to the index range [4000,8000]
> > and the lon range [-50,-30] should correspond to the index range
> > [13000:15000].
> >
> > This subset of data can then be downloaded using ncdump using this
> > command:
> > ncdump "
> > http://ourocean.jpl.nasa.gov:8080/thredds/dodsC/g1sst/sst_20100725.nc?SST[0:0][4000:8000][13000:15000]
> >
> > As you can see, there are several options for getting the data. The most
> > useful
> > of these would probably be to adopt the use of an application that supports
> > direct, programmatic access to data hosted on OPeNDAP servers.
> >
> > Cheers,
> >
> > Tom
> > --
> >
> > ****************************************************************************
> > Unidata User Support UCAR Unidata
> > Program
> > (303) 497-8642 P.O. Box
> > 3000
> > address@hidden Boulder, CO
> > 80307
> >
> > ----------------------------------------------------------------------------
> > Unidata HomePage http://www.unidata.ucar.edu
> >
> > ****************************************************************************
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: FJY-535537
> > Department: Support THREDDS
> > Priority: Normal
> > Status: Closed
> >
> >
>
>
> --
> _____________________________________________________
>
> Ricardo Domingues
>
> Marinha do Brasil
> Instituto de Estudos do Mar Almirante Paulo Moreira - IEAPM
> Rua Kioto, 253 - Praia dos Anjos, Arraial do Cabo, RJ - Brasil
> 28930-000
>
> Brazilian Navy
> Admiral Paulo Moreira Marine Research Institute - IEAPM
> Rua Kioto, 253 - Praia dos Anjos, Arraial do Cabo, RJ - Brasil
> 28930-000
>
> Phone: +55 (21) 8025 3735
> Skype: ricardo.oceano
> C. Lattes: http://lattes.cnpq.br/2759683877922229
>
>
Ticket Details
===================
Ticket ID: FJY-535537
Department: Support THREDDS
Priority: Normal
Status: Open