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[netCDF #QOP-799183]: output netCDF variables

Hi Mike,

> I am a researcher at a US university and am using netCDF to process data.
> I'm trying to output variables that I have read into the program using
> netCDF. Attached is my fortran program. The data file I'm using is here:
> 
> ftp://ftp.cdc.noaa.gov/Datasets/NARR/Dailies/monolevel/air.2m.1980.nc
> 
> I am able to successfully read in each variable from the netCDF file, but
> am unsure how to output them to a new netCDF file. The error I get is:
> 
> NetCDF: Variable not found
> STOP Error writing variable lat
> 
> I'm wondering if I need to define a new variable before writing to file.
> It should be obvious what I'm doing in this simple example. That's in
> advance for the help.

Yes, after you create a new netCDF file, it is empty, with no
dimensions, variables, or attributes.  Before writing data to a
variable, you must define the necessary dimensions, define the
variable, leave define mode, then write to the file.  The error you
are getting is because "ID_lat" is a variable ID for the open file you
are reading, but has no meaning for the open file you are trying to
write.  When you define a variable in the output filem the NF_DEF_VAR
function will return a variable ID you can use to refer to that
variable.  In general, variables in different files have different
variable IDs, even if they have the same names.  

It may help to look at an example program for creating and writing a
file, which you can find here:

  http://www.unidata.ucar.edu/software/netcdf/examples/programs/

--Russ

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



Ticket Details
===================
Ticket ID: QOP-799183
Department: Support netCDF
Priority: Normal
Status: Closed