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ncattdef: Attribute changer for NetCDF files


Synopsis

ncattdef [-h] ncName [defName]

Parameters

Parameters in [ ] are optional.
-h
Prints help information and quits.
ncName
Name of the NetCDF file to process - must be the first parameter.
defName
Name of file containing attribute definitions in CDL syntax.

Discussion

The program ncattdef opens the existing NetCDF file named ncName. It then parses the contents of defName or stdin, if defName was omitted and adds global and variable attributes to ncName if possible. Only valid CDL attribute definitions are accepted. Syntax errors are reported on stderr and parsing is continued.
Note:
Specifying an empty attribute value causes ncattdef to delete the attribute if it exists. This feature is not specified in the CDL syntax description.

Examples

ncattdef rrr.nc definitions.txt
Opens rrr.nc and changes its attributes according to the CDL definitions in definitions.txt
ncattdef rrr.nc definitions.txt >& /dev/null
Same as before but doesn't print error messages.
echo Blocks:identifier = "pgm raw" ; | ncattdef Blocks.nc
Opens Blocks.nc and adds the attribute identifier with the value "pgm raw" to the variable Blocks.
ncdump ncName1 | grep variableName | ncattdef ncName2
Copies all attributes of variableName from ncName1 to ncName2, as far as possible.

Return Values

These values can be returned as exit status by ncattdef:
PipsOk (0)
Program terminated normally.
PipsErrorFileRead (-1)
The definitions file could not be opened.
PipsErrorFileWrite (-2)
The NetCDF file could not be written or closed.
PipsNetcdfMissing (-4)
There haven't been specified any command line parameters.
PipsBadParameter (-5)
An unknown command line option; filenames must not start with a hyphen.

Restrictions and known bugs


Frank Heimes (Dr-Frank.Heimes@epost.de), 31 Jan 1995
Phone: +49 (721) 6091 - 424, FAX: +49 (721) 6091 - 233
http://members.tripod.de/DrFrankHeimes/pips/ncattdef.html