ncra (1) - Linux Manuals
ncra: netCDF Record Averager
NAMEncra - netCDF Record Averager
SYNTAXncra [-3] [-4] [-6] [-7] [-A] [--bfr sz][-C][-c][--cnk_byt sz][--cnk_dmn nm,sz] [--cnk_map map] [--cnk_plc plc] [--cnk_scl sz][-D dbg_lvl] [-d dim,[ min][,[ max]][, stride[[,[ subcycle]]]]] [--dbl|flt] [-F] [-G gpe_dsc] [-g grp[,...]] [-h] [--hdf] [--hdr_pad sz] [-L dfl_lvl] [-l path] [--mro] [--msa] [-n loop] [--no_cll_mth] [--no_tmp_fl] [-O] [-p path] [-R] [-r] [--ram_all] [--rec_apn] [-t thr_nbr] [--unn] [-v var[,...]] [-X box] [-x] [-y op_typ] input-files output-file
ncra averages record variables across an arbitrary number of input files. The record dimension is retained as a degenerate (size 1) dimension in the output variables.
Input files may vary in size, but each must have a record dimension. The record coordinate, if any, should be monotonic for (or else non-fatal warnings may be generated). Hyperslabs of the record dimension which include more than one file are handled correctly. ncra supports the stride argument to the -d hyperslab option for the record dimension only, stride is not supported for non-record dimensions.
ncra weights each record (e.g., time slice) in the input-files equally. ncra does not attempt to see if, say, the time coordinate is irregularly spaced and thus would require a weighted average in order to be a true time average.
ncra 85.nc 86.nc 87.nc 88.nc 89.nc 8589.nc
ncra 8.nc 8589.nc
ncra -n 5,2,1 85.nc 8589.nc
Assume the files
ncra -d time,11,13 85.nc 86.nc 87.nc 8512_8602.nc
ncra -F -d time,12,14 85.nc 86.nc 87.nc 8512_8602.nc
- ncra -F -d time,3,,12 -v temperature 85.nc 86.nc 87.nc 858687_03.nc
Assume the time coordinate is incrementally numbered such that January, 1985 = 1 and December, 1989 = 60. Assuming ?? only expands to the five desired files, the following averages June, 1985--June, 1989:
- ncra -d time,6.,54. ??.nc 8506_8906.nc
AUTHORNCO manual pages written by Charlie Zender and originally formatted by Brian Mays.
REPORTING BUGSReport bugs to <http://sf.net/bugs/?group_id=3331>.
COPYRIGHTCopyright © 1995-2014 Charlie Zender
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
HOMEPAGEThe NCO homepage at <http://nco.sf.net> contains more information.
SEE ALSOThe full documentation for NCO is maintained as a Texinfo manual called the NCO User's Guide. Because NCO is mathematical in nature, the documentation includes TeX-intensive portions not viewable on character-based displays. Hence the only complete and authoritative versions of the NCO User's Guide are the PDF (recommended), DVI, and Postscript versions at <http://nco.sf.net/nco.pdf>, <http://nco.sf.net/nco.dvi>, and <http://nco.sf.net/nco.ps>, respectively. HTML and XML versions are available at <http://nco.sf.net/nco.html> and <http://nco.sf.net/nco.xml>, respectively.
If the info and NCO programs are properly installed at your site, the command
- info nco
should give you access to the complete manual, except for the TeX-intensive portions.