NAME
ncrename - netCDF Renamer
SYNTAX
ncrename [-a old_name,new_name] [-a ... ] [-D] [-d old_name,new_name]
[-d ... ] [-h] [-l path] [-O] [-p path] [-R] [-r] [-v
old_name,new_name] [-v ... ] input-file [ output-file]
DESCRIPTION
ncrename renames dimensions, variables, and attributes in a netCDF
file. Each object that has a name in the list of old names is renamed
using the corresponding name in the list of new names. All the new
names must be unique. Every old name must exist in the input file,
unless the name is preceded by the character .. The validity of the
old names is not checked prior to the renaming. Thus, if an old name
is specified without the the . prefix and is not present in input-
file, ncrename will abort.
ncrename is the exception to the normal rules that the user will be
interactively prompted before an existing file is changed, and that a
temporary copy of an output file is constructed during the operation.
If only input-file is specified, then ncrename will change the names of
the input-file in place without prompting and without creating a
temporary copy of input-file. This is because the renaming operation
is considered reversible if the user makes a mistake. The new_name can
easily be changed back to old_name by using ncrename one more time.
Note that renaming a dimension to the name of a dependent variable can
be used to invert the relationship between an independent coordinate
variable and a dependent variable. In this case, the named dependent
variable must be one-dimensional and should have no missing values.
Such a variable will become a coordinate variable.
According to the netCDF User’s Guide, renaming properties in netCDF
files does not incur the penalty of recopying the entire file when the
new_name is shorter than the old_name.
OPTIONS
-a old_name, new_name Attribute renaming. The old and new names of
the attribute are specified by the associated old_name and
new_name values. Global attributes are treated no differently
than variable attributes. This option may be specified more
than once. You cannot change the attribute name for one
particular variable (unless it is uniquely named); all
occurrences of the attribute of a given name will be renamed.
This is considered an oversight and will be addressed in a
future version of NCO.
-d old_name, new_name Dimension renaming. The old and new names of
the dimension are specified by the associated old_name and
new_name values. This option may be specified more than once.
-v old_name, new_name Variable renaming. The old and new names of
the variable are specified by the associated old_name and
new_name values. This option may be specified more than once.
-i Interactive. ncrename will prompt for confirmation before
overwriting an existing file.
EXAMPLES
Rename the variable p to pressure and t to temperature in netCDF in.nc.
In this case p must exist in the input file (or ncrename will abort),
but the presence of t is optional:
ncrename -v p,pressure -v .t,temperature in.nc
ncrename does not automatically attach dimensions to variables of the
same name. If you want to rename a coordinate variable so that it
remains a coordinate variable, you must separately rename both the
dimension and the variable:
ncrename -d lon,longitude -v lon,longitude in.nc
Create netCDF out.nc identical to in.nc except the attribute _FillValue
is changed to missing_value (in all variables which possess it) and the
global attribute Zaire is changed to Congo:
ncrename -a _FillValue,missing_value -a Zaire,Congo in.nc out.nc
AUTHOR
NCO manual pages written by Charlie Zender and Brian Mays.
REPORTING BUGS
Report bugs to <http://sf.net/bugs/?group_id=3331>.
COPYRIGHT
Copyright © 1995-2010 Charlie Zender
This is free software; see the source for copying conditions. There is
NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE.
SEE ALSO
The full documentation for NCO is maintained as a Texinfo manual called
the NCO User’s Guide. Because NCO is mathematical in nature, the
documentation includes TeX-intensive portions not viewable on
character-based displays. Hence the only complete and authoritative
versions of the NCO User’s Guide are the PDF (recommended), DVI, and
Postscript versions at <http://nco.sf.net/nco.pdf>,
<http://nco.sf.net/nco.dvi>, and <http://nco.sf.net/nco.ps>,
respectively. HTML and XML versions are available at
<http://nco.sf.net/nco.html> and <http://nco.sf.net/nco.xml>,
respectively.
If the info and NCO programs are properly installed at your site, the
command
info nco
should give you access to the complete manual, except for the TeX-
intensive portions.
HOMEPAGE
The NCO homepage at <http://nco.sf.net> contains more information.