[netcdfgroup] netCDF Operators NCO version 4.9.9 are swarming

• To: NCO Announce Mail List <nco-announce@xxxxxxxxxxxxxxxxxxxxx>, netcdfgroup@xxxxxxxxxxxxxxxx
• Subject: [netcdfgroup] netCDF Operators NCO version 4.9.9 are swarming
• From: Charlie Zender <zender@xxxxxxx>
• Date: Fri, 14 May 2021 10:07:14 -0700

The netCDF Operators NCO version 4.9.9 have arrived.

http://nco.sf.net (Homepage, Mailing lists, Help)
http://github.com/nco (Source Code, Issues, Releases, Developers)

What's new?
Version 4.9.9 contains more fixes than features, and can probably be
skipped by those who do not use ncremap or ncclimo. ncclimo now
supports the mth_srt/end options for high resolution timeseries that
do not begin/end in Jan/Dec (previously it only supported those
arguments for monthly resolution). ncremap has crucial fixes for
weight generation and map-checking for masked grids, fixes for
curvilinear grid inferral, and automatic rounding when regridding
integer-valued fields (like masks).

Work on NCO 5.0.0 has commenced and will continue improving support
for analysis of land surface datasets packed into sparse-1D formats,
and ncremap support for the MOAB regridding package mbtempest.

Enjoy,
Charlie

NEW FEATURES (full details always in ChangeLog):

A. ncclimo now supports options --mth_srt and --mth_end in
   high-frequency splitter mode. Previously it only supported those
   arguments for monthly resolution timeseries. The arguments specify
   the (1-based) month in which the requested high-frequency
   timeseries should begin and end, respectively. These default to 1
   (January) and 12 (December). To extract 14-month timeseries from
   high frequency (e.g., daily-resolution) input files one would
   use, e.g.,
   ncclimo --clm_md=hfs --yr_srt=1 --yr_end=2 --mth_srt=4 --mth_end=5 ...
   http://nco.sf.net/nco.html#ncclimo
   http://nco.sf.net/nco.html#mth_srt
   http://nco.sf.net/nco.html#mth_end

B. ncclimo is now smarter about inferring both the temporal
   resolution of high frequency timeseries, and the number of
   timesteps per file. As a result, explicit invocation of the tpd
   (timesteps-per-day) and dpf (days-per-file) option should no longer
   be necessary. Explicitly specifying these options will, of course,
   prevent ncclimo from trying to infer them.
   ncclimo --clm_md=hfs           ... # This should work fine
   ncclimo --clm_md=hfs --tpd=8   ... # No longer necessary
   ncclimo --clm_md=hfs --dpf=10  ... # No longer necessary
   http://nco.sf.net/nco.html#ncclimo
   http://nco.sf.net/nco.html#tpd
   http://nco.sf.net/nco.html#dpf

C. ncremap now automatically rounds integer-valued fields, such as
   masks. Previously when ncremap regridded an integer-valued field,
   it used implicit type-conversion rules to convert the regridded
   destination value to an integer value for output. However, users
   generally expect a regridded value of, say, 1.9999999, to be
   converted to the integer 2 not 1. Hence, ncremap now automatically
   applies the rint() function to internal floating point values
   before converting them to integers for output. Regrid integer
   valued fields such as masks now generally behave as desired.

D. ncremap now always invokes TempestRemap's GenerateOverlapMesh with
   its --allow_no_overlap option. This option permits TR to generate
   meshes from not-completely-overlapped regional grids. This is often
   useful in post-processing regional data, for example.
   http://nco.sf.net/nco.html#tr
   http://nco.sf.net/nco.html#allow_no_overlap

E. Conda builds should now be more robust, due to extensive testing.
   Thanks to Xylar Asay-Davis for helping us understand and alter the
   nco-feedstock for Conda. As a result of this, OpenMP should work
   on all MacOS Conda installations, and thus make map-file generation
   much faster for high-resolution maps.

F. This version works-around a regression in netCDF 4.7.4 (fixed in
   4.8.0) that prevents NCO from manipulating HDF4 files, and a
   regression in netCDF 4.8.0 (subsequently fixed in 4.8.1) that
   prevents NCO from building its main test file from CDL, and thus
   prevents NCO from building without manual intervention.

--
Charlie Zender, Earth System Sci. & Computer Sci.
University of California, Irvine 949-891-2429 )'(