4.4 Get a Variable ID from Its Name: nc_inq_varid

The function nc_inq_varid returns the ID of a netCDF variable, given its name.

Usage

     int nc_inq_varid (int ncid, const char *name, int *varidp);

ncid

NetCDF ID, from a previous call to nc_open or nc_create.

name

Variable name for which ID is desired.

varidp

Pointer to location for returned variable ID.

Errors

nc_inq_varid returns the value NC_NOERR if no errors occurred. Otherwise, the returned status indicates an error. Possible causes of errors include:

• The specified variable name is not a valid name for a variable in the specified netCDF dataset.
• The specified netCDF ID does not refer to an open netCDF dataset.

Example

Here is an example using nc_inq_varid to find out the ID of a variable named rh in an existing netCDF dataset named foo.nc:

     #include <netcdf.h>
        ...
     int  status, ncid, rh_id;
        ...
     status = nc_open("foo.nc", NC_NOWRITE, &ncid);
     if (status != NC_NOERR) handle_error(status);
        ...
     status = nc_inq_varid (ncid, "rh", &rh_id);
     if (status != NC_NOERR) handle_error(status);