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[netCDF #FJH-116834]: questions regarding udunits

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  • Subject: [netCDF #FJH-116834]: questions regarding udunits
  • Date: Tue, 15 Apr 2008 10:39:28 -0600
Hi,

> Other questions:
> 1. Is it possible to have a variable (for station data) where char
> type is used as a dimension? You have any example?

Yes, you can use a char type for a coordinate variable, if that's what you
mean.
Since the maximum value of a signed char is 127, this would only work if you
have 127 or fewer values for the dimension.  Here is an example of the CDL,
and you can make the corresponding netCDF file using "ncgen -b CDLFILE":
netcdf noman {
dimensions:
   stno = 5;
   namelen = 20;
variables:
   char stno(stno);   // character coordinate variable, < 127 stations
   char station_name(stno, namelen);
data:
   station_name = "abc", "defg", "paris", "london", "san diego";
}

> 2. For gridded data, I believe there is an attribute to specify
> whether the location is cell center or not. What is that attribute and
> acceptable values? Is this attribute CF complainant?

I think you need to use the "bounds" attribute on the coordinate variables.
A description is in the CF section "7. Data Representative of Cells" at

  
http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.1/cf-conventions.html#id2618835

If you want the center of the cell to represent all the values in the cell, you
may
need to use the "cell_methods" attribute, which is described in the same
section.

--Russ

Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: FJH-116834
Department: Support netCDF
Priority: Normal
Status: Closed