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Rename an Attribute

The function ncattrename (or NCAREN for FORTRAN) changes the name of an attribute. If the new name is longer than the original name, the netCDF must be in define mode. You cannot rename an attribute to have the same name as another attribute of the same variable.

In case of an error, ncattrename returns -1; NCAREN returns a nonzero value in rcode. Possible causes of errors include:

• The specified variable ID is not valid.
• The new attribute name is already in use for another attribute of the specified variable.
• The specified netCDF file is in data mode and the new name is longer than the old name.
• The specified attribute does not exist.
• The specified netCDF ID does not refer to an open netCDF file.

ncattrename: C Interface

int ncattrename (int ncid, int varid, const char* name, const char* newname);

ncid

NetCDF ID, returned from a previous call to ncopen or nccreate

varid

ID of the attribute's variable, or NC_GLOBAL for a global attribute

name

The original attribute name.

newname

The new name to be assigned to the specified attribute. If the new name is longer than the old name, the netCDF file must be in define mode.

Here is an example using ncattrename to rename the variable attribute units to Units for a variable rh in an existing netCDF file named `foo.nc':

#include "netcdf.h"
   ...
int  ncid;        /* netCDF ID */
int  rh_id;       /* variable id */
   ...
ncid = ncopen("foo.nc", NC_NOWRITE);
   ...
rh_id = ncvarid (ncid, "rh");
   ...
/* rename attribute */
ncattrename(ncid, rh_id, "units", "Units");

NCAREN: FORTRAN Interface

      SUBROUTINE NCAREN (INTEGER NCID, INTEGER VARID,
     +                   CHARACTER*(*) ATTNAM,
     +                   CHARACTER*(*) NEWNAM, INTEGER RCODE)

NCID

NetCDF ID, returned from a previous call to NCOPN or NCCRE

VARID

ID of the attribute's variable, or NCGLOBAL for a global attribute

ATTNAM

The original attribute name.

NEWNAM

The new name to be assigned to the specified attribute. If the new name is longer than the old name, the netCDF file must be in define mode.

RCODE

Returned error code. If no errors occurred, 0 is returned.

Here is an example using NCAREN to rename the variable attribute units to Units for a variable rh in an existing netCDF file named `foo.nc':

      INCLUDE "netcdf.inc"
         ...
      INTEGER  NCID     ! netCDF ID
      INTEGER  RHID      ! variable ID
         ...
      NCID = NCOPN ("foo.nc", NCNOWRIT, RCODE)
         ...
      RHID = NCVID (NCID, "rh", RCODE)
         ...
* rename attribute
      CALL NCAREN (NCID, RHID, "units", "Units", RCODE)

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