CDO

• select, delete: added wildcard support for parameter name
• expr: added support for logical operators <, >, <=, >=, !=, ==, <=>

• splityearmon: Split in years and months
• yseasadd: Add multi-year seasonal time series
• yseassub: Subtract multi-year seasonal time series
• yseasmul: Multiply multi-year seasonal time series
• yseasdiv: Divide multi-year seasonal time series

• vertmean, vertavg: changed to weighted means if layer bounds are available
• setpartabp, setpartabn: added optional parameter convert to convert the units.
  Units are not converted anymore if this parameter is not set!
• TimSTAT, Timpctl, TimselSTAT, Timselpctl, SeasSTAT, Seaspctl:
  The output time stamp of all operators from the above modules are changed from the last to the middle contributing timestep.
  Use the environment variable CDO_TIMESTAT_DATE=last to set the output time stamp to the last contributing timestep.
• eof, eof3d: use area weights instead of no weights
  Use the environment variable CDO_WEIGHT_MODE=off to switch back to the non weighted version

• gradsdes: grib index file is empty (introduced in 1.6.7)
• grib2 output: segfaults when writing grib2 files [Bug #5351]
• remapnn: Segmentation fault for extrapolation of regular 2D source grids [Bug #5448]

• outputtab: table output

• option -t table: segmentation fault if parameter table entry longname is missing
• merge: check number of timesteps [Bug #5338]
• seasmean: sets all time_bnds to the same values [Bug #5329]
• histcount: doesn't recognize missing values
• filesdes: doesn't work for GRIB2 files [Bug #5307]

• distgrid: distribute horizonal grid
• collgrid: collect horizontal grid

• cat: added support for option -O (overwrite existing output file)
• remaplaf: changed calculation of weights from SCRIP to YAC

• gridarea: added support for concave grid cells
• gradsdes: added support for option 365_day_calendar
• import_binary: option 365_day_calendar does not work
• select: wrong result when select only one timestep

• Option --history: Do not append to netCDF "history" global attribute
• Option --netcdf_hdr_pad <nbr>: Pad netCDF output header with nbr bytes

• setpartabn: set parameter table by name
• setpartabp: set parameter table by parameter ID
• sealevelpressure: sea level pressure

• Sinfo: changed format of grid and zaxis section
• Filter: disable zero-padding
• diff: print number of different values
• Ymonstat: sorts output by month of year

• eof3d: set sum of weights to 1
• eofcoeff: remove scaling with grid cell area weights
• eofcoeff3d: remove scaling with grid cell area weights

• remapbil, remapbic, remapdis, remapnn: performance optimization for regular 2D source grids
• gradsdes: added support for GRIB files >2GB
• eca_csu: added number of csu periods with more than 5days per time period
• eca_cfd: added number of cfd periods with more than 5days per time period
• expr: select variables by name

• gradsdes: added parameter map_version and removed specific operators gradsdes1 and gradsdes2

• gradsdes: changed LCC to LCCR in PDEF definition [Bug #4344]
• cat: "Segmentation fault" if the output file already exist [Bug #4291]
• delete: parameter level does not work [Bug #4216]

• select: added support for key >timestep_of_year<
• mastrfu: added missing value support
• splitmon: added optional parameter to set the format string for the month

• selyear: wrong result for negative years [Bug #3836]
• eca_gsl: start date of growing season is wrong if the length of growing season is zero

• support of blanks in filenames and parameter

• gradsdes: added support for netCDF files
• Info: add chunking information of netcdf files (only with verbose output) [Feature #3489]
• select: added support for key >hour<

• fldcor: check missing value of 2. input file
• enscrps: wrong result since CDO version 1.5.6 [Bug #3403]
• selmon: month not found for negative years [Bug #3439]
• shifttime: wrong result for negative hours and days [Bug #3440]
• inttime: removes last time step [Bug #3611]

• select: Select fields from an unlimited number of input files
• mergegrid: Merge horizontal grids
• yearmonmean: yearly mean from monthly data
• duplicate: Duplicates a dataset
• adisit: Potential temperature to in-situ temperature
• rhopot: Calculates potential density

• setcalendar: changed CDO calendar names to CF calendar names (Feature #3123)
  (standard, proleptic_gregorian, 360_day, 365_day, 366_day)
• masklonlatbox: added support for curvilinear grids
• diff: print only records that differ

• sellonlatbox: wrong result with overlapped lonlatbox on curvilinear grids
• ensrkhisttime: fixed memory fault
• expr: wrong result for operation var1/var2 where var2 = 0
• Runstat: added support for time bounds (Bug #3127)
• merge: uses size of the first input file for the output buffer

• cdo option -z zip: added optional compression level -z zip[_1-9]
• cdo: added option -k <chunktype> to set the chunk type to auto, grid or lines
• Added workaround to combine CDO operators with the result of mergetime, merge, copy, cat, ens<STAT>
  (use one input parameter with wildcards in single quotes, e.g.: 'ifile?_*')

• enlarge: added missing value support

• gradsdes: failed
• sellevel: loosing level bounds
• wrong result for user defined lonlat grids with xfirst < 0
  (This bug was introduced in CDO version 1.5.8)

New Feature:

• new return option: Masked Arrays
  if the new keyword returnMaArray is given, its value is taken as variable
  name and a masked array wrt to its FillValues is returned, examples for python and ruby can be found in the unit tests
  contribution for python by Alex Loew
• Error handling: return stderr in case of non-zero return value + raise exception
  contribution for python from Estanislao Gonzalez (#3047)
• Autocompletion and built-in documentation through help() for interactive use
  contribution from Estanislao Gonzalez [python] (#3048)
• Added help operator for displaying help interactively [ruby]
  "sample": https://github.com/Try2Code/cdo-bindings/blob/master/ruby/test/test_cdo.rb#L299

Installation works as usual with pip and gem.