NetCDF operators (NCO) version 5.0.1

Version 5.0.1 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:

Version 5.0.1 contains the necessary options for ncremap to exploit MPI-enabled weight generators such as ESMF_RegridWeightGen. You can probably skip this release unless you use ncremap.

New Features

1. ncremap accepts two new and related options, mpi_pfx and mpi_nbr. The --mpi_pfx=mpi_pfx option specifies an appropriate job scheduler prefix for MPI-enabled weight-generation executables such as ESMF's ESMF_RegridWeightGen and MoabTempest's mbtempest. Other weight generators (ncks, GenerateOfflineMap) are unaffected by this option since they are not MPI-enabled. mpi_pfx defaults to mpirun -n $mpi_nbr on all machines except those whose $HOSTNAME matches an internal database of DOE-operated supercomputers where mpi_pfx defaults to srun -n $mpi_nbr. When invoking --mpi_pfx, be sure to explicitly define the number of MPI tasks-per-node, e.g.,

   ncremap --mpi_pfx='srun -n 16' ...  
   ncremap --mpi_pfx='srun --mpi=pmi2 -n 4' ...

   The separate --mpi_nbr=mpi_nbr option specifies the number of tasks-per-node that MPI-enabled weight generators will request. It preserves the default job scheduler prefix (srun or mpirun):

   ncremap --mpi_nbr=4 ... # 16 MPI tasks-per-node for ERWG/mbtempest  
   ncremap --mpi_nbr=16 ... # 4 MPI tasks-per-node for ERWG/mbtempest

   Thus --mpi_nbr=mpi_nbr can be used to create host-independent ncremap commands to facilitate benchmarking the scaling of weight-generators across hosts that work with the default value of mpi_pfx. The --mpi_pfx option will prevail and --mpi_nbr will be ignored if both are used in the same ncremap invocation. Note that mpi_pfx is only used internally by ncremap to exploit the MPI capabilities of select weight-generators. It is not used to control and does not affect the distribution of multiple ncremap commands among a cluster of nodes.
   https://nco.sf.net/nco.html#mpi_pfx
   https://nco.sf.net/nco.html#mpi_nbr

Additional details are available in the ChangeLog.