[netcdfgroup] netCDF operators NCO version 3.9.2 are ready

• To: NCO Announce Mail List <nco-announce@xxxxxxxxxxxxxxxxxxxxx>, netCDF Mail List <netcdfgroup@xxxxxxxxxxxxxxxx>
• Subject: [netcdfgroup] netCDF operators NCO version 3.9.2 are ready
• From: Charlie Zender <zender@xxxxxxx>
• Date: Fri, 31 Aug 2007 15:11:35 -0700

The netCDF operators NCO version 3.9.2 are ready.

http://nco.sf.net (Homepage)
http://dust.ess.uci.edu/nco (Homepage "mirror")

First, the NCO licenses have changed from GPL2 (code) and FDL1.1
(documentation) to GPL3 (code) and FDL1.2 (documentation).

Second, 3.9.2 also introduces ncap2 printing and type-conversion
and beta-support for UDUnits2. As usual the latest build
and compile tweaks have been made to improve portability.

Finally, the major user-visible change is that the default attribute
if any, specifying the value of data to ignore has (finally) changed
from "missing_value" to "_FillValue".
Supporting both of these attributes simultaneously is not practical.
Hence the behavior NCO used to apply to missing_value's now applies to
_FillValue's---missing_value's are now treated as normal data.
The NCO user's guide shows how to ease migration to this new behavior.

A. Change from GPL2 to GPL3
   http://www.gnu.org/copyleft/gpl.html

B. UDUnits2 beta-support. Compile with 'UDUNITS2=Y', send us feedback.
   Binaries (RPMs, Debs) still use UDUnits1. Thanks to Steve Emmerson.
   http://nco.sf.net/nco.html#UDUnits2

C. Ignore data equal to _FillValue (rather than missing_value)
   Hints and examples to handle new or to revert to old behavior:
   http://nco.sf.net/nco.html#_FillValue

D. Improved Documentation:
   Working with non-standard grids, e.g., 2D grids fxm
   http://nco.sf.net/nco.html#grd

E. ncap2 continues to grow more powerful (Henry Butowsky)
   All functions (e.g., cos(), avg()) are now available as methods
   (e.g., var.cos(), var.avg(x,y))
   Demonstration scripts ~/nco/data/[bin_cnt.nco,psd_wrf.nco]

F. ncap2 supports type conversion (Henry Butowsky)
   ncap2 -s 'big_int=uint64(small_int)+double(small_int);' in.nc out.nc
   http://nco.sf.net/nco.html#ncap2

G. ncap2 now prints variables and metadata (Henry Butowsky)
   ncap2 -s 'foo=1;print(foo)' in.nc out.nc
   http://nco.sf.net/nco.html#ncap2

H. Pre-built, up-to-date, Debian Sid & Ubuntu binaries are available.
   http://nco.sf.net#debian

I. Pre-built, up-to-date, RPM packages are available.
   http://nco.sf.net#rpm

J. Reminder: NCO support for netCDF4 features is tracked at

   http://nco.sf.net/nco.html#nco4

   NCO currently supports netCDF4 atomic data types and compression.
   NCO 3.9.2 with netCDF4 support should work with HDF5 1.8 beta2
   and netCDF4 snapshot20070822 and newer.

   export NETCDF4_ROOT=/usr/local/netcdf4 # Set netCDF4 location
   cd ~/nco;./configure --enable-netcdf4  # Configure mechanism -or-
   cd ~/nco/bld;./make NETCDF4=Y allinone # Old Makefile mechanism

The next release will debut a user-friendly version of SWAMP, the NCO
server-side processor (http://dust.ess.uci.edu/ppr/ppr_WZJ073.pdf).

Enjoy,
Charlie
-- 
Charlie Zender, Department of Earth System Science, UC Irvine
Visiting LGGE until 20080715 :) Voice: 011+33+476+824236
Laboratoire de Glaciologie et Geophysique de l'Environnement
BP 96, 54 rue Moliere, 38402 Saint Martin d'Heres Cedex, France