Anotinio et al,
Thanks for your help. The command line option is attractive and I will give
that a try. One thing that eludes me is how to specify the ranges for
latitude and longitude correctly.
If for instance I would like data for the Bay of Bengal BB defined by
(0N,75E) (25N,99E), how would I specify this in the infile. I do see the
DDS parameters, but am unclear how to formulate the ranges or even how to
determine what the corresponding ranges are, given a geographic bounding
box.
Help on this would be greatly appreciated. Perhaps there is some
documentation with some examples?
Harper
On Fri, Jun 21, 2013 at 10:09 AM, "Antonio S. Cofiño" <
antonio.cofino@xxxxxxxxx> wrote:
> Harper,
>
> You can use the NetCDF library with opendap capabilities:
> http://www.unidata.ucar.edu/**software/netcdf/docs/netcdf/**
> DAP-Support.html<http://www.unidata.ucar.edu/software/netcdf/docs/netcdf/DAP-Support.html>
>
> more exactly the nccopy tool:
> http://www.unidata.ucar.edu/**software/netcdf/docs/netcdf/**nccopy.html<http://www.unidata.ucar.edu/software/netcdf/docs/netcdf/nccopy.html>
>
> which can be used to copy the remote data to a local file. The nccopy will
> download the whole dataset in small sets based on the buffer parameter:
>
> For example,
> nccopy -k 4 -d 9 -s -u http://ncss1.hycom.org/**
> thredds/dodsC/GLBa0.08/expt_**90.9/2013/uvel<http://ncss1.hycom.org/thredds/dodsC/GLBa0.08/expt_90.9/2013/uvel>
> uvel.nc
>
> will download the 346863.0 Mbytes to a local NetCDF file named uvel.nc.
> (please look the doc, dfor the meaning of the -k, -d and -s flags)
>
> If you want to download just a subset of the whole dataset, you can you
> use the subset form:
> http://ncss1.hycom.org/**thredds/dodsC/GLBa0.08/expt_**90.9/2013/uvel.html<http://ncss1.hycom.org/thredds/dodsC/GLBa0.08/expt_90.9/2013/uvel.html>
>
> make all your selectiosn for the subsetting and use the resulting "Data
> URL" as the "infile" argument for the nccopy command.
>
> I hope this helps
>
> Regards
>
> Antonio
>
> --
> Antonio S. Cofiño
> Grupo de Meteorología de Santander
> Dep. de Matemática Aplicada y
> Ciencias de la Computación
> Universidad de Cantabria
> http://www.meteo.unican.es
>
> El 21/06/2013 1:33, Harper Simmons escribió:
>
>>
>> Thanks Michael.
>>
>> I was helped by John Maurer and made some progress on a smaller
>> extraction that I needed to perform. Unfortunately when trying to perform
>> an extraction for a larger area, probably amounting to several GB, I ran
>> into what John M. identified as a 500MB limit on the opendap back end.
>>
>> I am trying to learn do construct my extraction with matlab 2012b since
>> limiting my queries to 500MB per query is proving to be too time intensive
>> to accomplish interactively. I was hoping that matlab's scripting
>> capabilities would make this painless.
>>
>> I have never used DoDs or opendap with matlab before but this far I am
>> also finding this to be extremely slow (45 minutes to extract just the
>> latitude data or just the longitude data). Would using the URL below
>> possibly work better for this?
>>
>> Harper
>>
>>
>> On Thu, Jun 20, 2013 at 3:25 PM, Michael McDonald
>> <mcdonald@xxxxxxxxxxxxx<mailto:
>> mcdonald@xxxxxxxxxxxxx**>> wrote:
>>
>> Harper,
>> This is a server-side problem we are working on.
>> If you switch the URL over to one of our new test servers it will
>> work, e.g.,
>>
>> http://ncss1.hycom.org/**thredds/ncss/grid/GLBa0.08/**
>> expt_90.9/2013/uvel/dataset.**html<http://ncss1.hycom.org/thredds/ncss/grid/GLBa0.08/expt_90.9/2013/uvel/dataset.html>
>> http://ncss2.hycom.org/**thredds/ncss/grid/GLBa0.08/**
>> expt_90.9/2013/uvel/dataset.**html<http://ncss2.hycom.org/thredds/ncss/grid/GLBa0.08/expt_90.9/2013/uvel/dataset.html>
>>
>> We will be making "ncss.hycom.org <http://ncss.hycom.org>" into a
>>
>> load balance DNS-RR name
>> soon once we've verified that the new THREDDS servers are running
>> properly.
>>
>> /mike
>>
>>
>>
>> On Thu, Jun 20, 2013 at 1:28 PM, Harper Simmons
>> <hlsimmons@xxxxxxxxxx <mailto:hlsimmons@xxxxxxxxxx>> wrote:
>> >
>> > Dear Thredds,
>> >
>> > I am trying to extract a portion of the South China Sea over the
>> time period
>> > from April 1 to June 1 of this year and the data extraction
>> hangs for 10+
>> > minutes and then times out. I have tried smaller quieries
>> (smaller areas,
>> > less time) and have tried initiating from various machines and
>> browsers. I
>> > expect it is a server side problem rather than client side.
>> >
>> >
>> http://ncss.hycom.org/thredds/**ncss/grid/GLBa0.08/expt_90.9/**
>> 2013/uvel/dataset.html<http://ncss.hycom.org/thredds/ncss/grid/GLBa0.08/expt_90.9/2013/uvel/dataset.html>
>> >
>> > I have tried this both with single parameters (uvel) and
>> multiple parameters
>> > as I would like all of the 3D model state variables and 2D
>> forcing data.
>> >
>> > I am asking for the bounding box
>> >
>> > N = 24, S = 16, W = 116, E = 124
>> >
>> > Starting time = 2013-04-01T00:00:00Z
>> > Ending time = 2013-06-01T00:00:00Z
>> >
>> > Any help would be much appreciated
>> >
>> > Harper
>> >
>> >
>> > ______________________________**_________________
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>> <mailto:thredds@xxxxxxxxxxxx.**edu<thredds@xxxxxxxxxxxxxxxx>
>> >
>>
>> > For list information or to unsubscribe, visit:
>> >
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>>
>>
>>
>>
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