Version 4.5.5 of the netCDF Operators (NCO) has been released. NCO is an Open Source package that consists of a dozen standalone, command-line programs that take netCDF files as input, then operate (e.g., derive new data, average, print, hyperslab, manipulate metadata) and output the results to screen or files in text, binary, or netCDF formats.
The NCO project is coordinated by Professor Charlie Zender of the Department of Earth System Science, University of California, Irvine. More information about the project, along with binary and source downloads, are available on the SourceForge project page.
From the release message:
NCO fully supports CDF5-format datasets,
accrue useful features, and some corner case bugs were fixed.
NCO supports the CDF5 file type first introduced by pnetCDF
and now supported in Unidata netCDF as of version 4.4.0.
CDF5 uses 64-bit offsets for a large address space (like the
netCDF 64BIT type) AND arrays may have more than
232 elements. Use
Conversion to and between all netCDF filetypes is supported:
ncks -5 in_3.nc out_5.nc ncks -5 in_7.nc out_5.nc ncks -7 in_5.nc out_7.nchttp://nco.sf.net/nco.html#cdf5
ncremap: -Poption triggers filetype-specific workflow procedures (such as automatic permutation). Currently filetype-specific handling is defined for AIRS, HIRDLS, MLS, and MPAS files:
ncremap -P airs -i airs.nc -m map.nc -o out.nc ncremap -P hirdls -i airs.nc -m map.nc -o out.nc ncremap -P mls -i airs.nc -m map.nc -o out.nc ncremap -P mpas -i mpas.nc -m map.nc -o out.ncOne aspect of this handling is to rearrange dimension ordering from the way NASA/MPAS distributes generates these datasets so that horizontal spatial dimensions (lat, lon) come last. This is friendlier for regridding applications.
ncremap: -m map_flsupplies names to generated mapfiles and ncremap annotates map-files it creates with full history. This helps retain provenance in generated mapfiles. And ncremap has a friendlier mode, "map-only" mode, to generate mapfiles for later use. To use this mode, call ncremap without any input files to remap.
ncremap will then generate the mapfile then exit. ncremap -i in.nc -d dst.nc -m map.nc -o out.nc # Named mapfile ncremap -s grd_in.nc -g grd_out.nc -m map.nc # Map-only modehttp://nco.sf.net/nco.html#ncremap
ncremap -j job_nbroption for MPI parallelism
tabs()=total_absolute_value. The the
-y tabsoption is like
-y ttlexcept the sum is over absolute values.
mabs()are analogous to
nces -y tabs in.nc in.nc out.nc ncra -y tabs in.nc in.nc out.nc ncwa -y tabs in.nc out.nchttp://nco.sf.net/nco.html#op_typ
- Improve support for Cygwin builds
Additional details are available in the ChangeLog.