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Re: netCDF question....

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  • Subject: Re: netCDF question....
  • Date: Thu, 18 Dec 1997 16:46:15 -0700
> From: Leigh Angus <address@hidden>
> Subject: netCDF question....
> To: address@hidden
> Organization: FSL

Hi Leigh,

> My name is Leigh Angus and I am a meteorologist/programmer with CIRA  
> at the NOAA Forecast System Lab here in Boulder. 
> I sent you a question via email in the past and appreciated your quick and 
> helpful reply.  I have a quick question about netCDF access that I would 
> like to run by you.
> 
> First a bit of an overview of what we are trying to do.
> Our group over here is working on the Local Data Acquisition and 
> Dissemination (LDAD) feature for AWIPS.  The LDAD system basically
> has the responsibility of bringing into a weather forecast office all
> of the local surface weather data sets that might exist in a particular state.
> These data are then decoded and stored into netCDF data files.  In
> addition to storing these data into netCDF files, we have to 
> display the weather data on our D2D (AWIPS) workstation.  Our
> dillema is that it takes too long to read the data from the netCDF
> data files in time to display the data on the workstation screen.  
> 
> We are storing data from a bunch of weather stations in these netCDF
> data files.  There might be, for example,  5000 stations in a netCDF data
> file each reporting 10 or so pre-determined weather parameters
> (e.g., temperature, wind speed, etc..). So for each station in the
> netCDF file there is a value for the weather station name, its temperature,
> its wind speed, etc.  The UNLIMITED dimension is the number of records in
> the file, which is not known ahead of time.
> 
> So, my question for you is as follows.  Is there a way that we can
> read in a netCDF file in a piece of (C/C++ code, for example) in one
> "fread()" call and then parse out the individual fields from the
> netCDF file by some sort of byte/offset method?  We would also
> have to know how to read past the netCDF file header as well by
> knowing how much space the header takes up before the actual data values
> are stored.  We need FAST netCDF data access......
> 
> 
> I would appreciate any information you could provide on this matter.
> Thanks a lot.

I've forwarded your question to Glenn Davis, because I think he is
better qualified to answer this ...

--Russ