NetCDF Operators: Difference between revisions
From BAWiki
imported>Schade Peter (meaning of the option -h) |
imported>Schade Peter mNo edit summary |
||
| Line 31: | Line 31: | ||
* Execute the command with options, file names etc.: | * Execute the command with options, file names etc.: | ||
ncrcat -h file1.nc file2.nc result.nc | ncrcat -h file1.nc file2.nc result.nc | ||
* The option -h eliminates the attributes history and nco_openmp_thread_number. The latter causes an error when processing the output file with BAW programs as | * The option -h eliminates the attributes history and nco_openmp_thread_number. The latter causes an error when processing the output file with BAW programs as NCANALYSE. | ||
==Citations== | ==Citations== | ||
Revision as of 14:08, 9 June 2015
About NCO
The NCO toolkit manipulates and analyzes data stored in NetCDF-accessible formats, including DAP, HDF4, and HDF5. It exploits the geophysical expressivity of many CF (Climate & Forecast) metadata conventions, the flexible description of physical dimensions translated by UDUnits, the network transparency of OPeNDAP, the storage features (e.g., compression, chunking, groups) of HDF (the Hierarchical Data Format), and many powerful mathematical and statistical algorithms of GSL (the GNU Scientific Library). NCO is fast, powerful, and free.
For more information see nco.sourceforge.net.
Typical applications at BAW
Concatenation of several NetCDF files converted from boewrt.dat files into one cf-netcdf.nc file
- Verify original data for correctness and completeness;
- (optional) Transform boewrt.dat using ZEITRIO into equidistant time-series of identical length;
- Convert several boewrt.dat files using DATACONVERT to equivalent cf-netcdf.nc files (with identical dates and times);
- With ncrcat several files can be concatenated into one cf-netcdf.nc file;
- Typical post processors: NCANALYSE;
- Example: ncrcat -h f1.nc f2.nc ... fn.nc result.nc (-h suppresses the modification or creation of a history attribute);
- More information: ncrcat-netCDF-Record-Concatenator.
Availability at the BAW in Hamburg
- Status 04. Feb. 2015
- NCO commands are only available on Windows systems at the console level.
"Recipe" for execution on Windows systems
- Open the console in the data directory, e.g. in the TotalCommander:
-> Befehle -> Kommandozeilenfenster öffnen (TotalCommander language = German):
- Extend the search path:
set PATH = %PATH%;\\kepheus\system\akprog\bin\win
- Get help on the command, for example:
ncrcat
- Execute the command with options, file names etc.:
ncrcat -h file1.nc file2.nc result.nc
- The option -h eliminates the attributes history and nco_openmp_thread_number. The latter causes an error when processing the output file with BAW programs as NCANALYSE.
Citations
The recommended citations for NCO software are
- Zender, C. S. (2008), Analysis of Self-describing Gridded Geoscience Data with netCDF Operators (NCO), Environ. Modell. Softw., 23(10), 1338-1342, doi:10.1016/j.envsoft.2008.03.004.
- Zender, C. S. (2014), netCDF Operator (NCO) User Guide, Version 4.4.8, http://nco.sf.net/nco.pdf.
Use the former when referring to overall design, purpose, and optimization of NCO, and use the latter when referring to specific features and/or the User Guide itself.
back to Standard-Software-Applications (Add-ons)