ncap(1) [debian man page]
NCAP(1) General Commands Manual NCAP(1) NAME
ncap - netCDF Arithmetic Processor SYNTAX
ncap [-3] [-4] [-6] [-A] [-C] [-c] [-D dbg] [-F] [-f] [-h] [-L dfl_lvl] [-l path] [-O] [-o output-file] [-p path] [-R] [-r] [-S script- file][-s script][-v var[, ... ]] input-file [ output-file ] DESCRIPTION
ncap arithmetically processes a netCDF file. However, in about 2008 ncap was deprecated in favor of ncap2 which far surpasses its capbili- ties. ncap will eventually be completely removed from NCO. It is currently retained only because it provides an easier-to-build arith- metic operator than ncap2. The processing instructions are contained either in the NCO script file fl.nco or in a sequence of command line arguments. The options -s (or long options --spt or --script) are used for in-line scripts and -S (or long options --fl_spt or --script-file) are used to provide the filename where (usually multiple) scripting commands are pre-stored. ncap was written to perform arbitrary albebraic transformations of data and archive the results as easily as possible. Missing values are treated correctly. The results of the algebraic manipulations are called derived fields. Unlike the other operators, ncap does not accept a list of variables to be operated on as an argument to -v. Rather, the -v switch takes no arguments and indicates that ncap should output only user-defined variables. ncap does not accept or understand the -x switch. EXAMPLES
Compute the square of variable T ncap -s "T2=T*T" in.nc out.nc AUTHOR
NCO manual pages written by Charlie Zender and Brian Mays. REPORTING BUGS
Report bugs to <http://sf.net/bugs/?group_id=3331>. COPYRIGHT
Copyright (C) 1995-2010 Charlie Zender This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU- LAR PURPOSE. SEE ALSO
The 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. HOMEPAGE
The NCO homepage at <http://nco.sf.net> contains more information. NCAP(1)
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NCRA(1) General Commands Manual NCRA(1) NAME
ncra - netCDF Record Averager SYNTAX
ncra [-3] [-4] [-6] [-A] [-C] [-c] [-D dbg] [-d dim,[ min][,[ max]][,[ stride]]] [-F] [-h] [-L dfl_lvl] [-l path] [-n loop] [-O] [-p path] [-R] [-r] [-t thr_nbr] [-v var[,...]] [-X box] [-x] [-y op_typ] input-files output-file DESCRIPTION
ncra averages record variables across an arbitrary number of input files. The record dimension is retained as a degenerate (size 1) dimen- sion 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 sup- ports 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. EXAMPLES
Average files 85.nc, 86.nc, ... 89.nc along the record dimension, and store the results in 8589.nc: ncra 85.nc 86.nc 87.nc 88.nc 89.nc 8589.nc ncra 8[56789].nc 8589.nc ncra -n 5,2,1 85.nc 8589.nc These three methods produce identical answers. Assume the files 85.nc, 86.nc, ... 89.nc each contain a record coordinate time of length 12 defined such that the third record in 86.nc contains data from March 1986, etc. NCO knows how to hyperslab the record dimension across files. Thus, to average data from December, 1985 through February, 1986: 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 The file 87.nc is superfluous, but does not cause an error. The -F turns on the Fortran (1-based) indexing convention. The following uses the stride option to average all the March temperature data from multiple input files into a single output file 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 AUTHOR
NCO manual pages written by Charlie Zender and Brian Mays. REPORTING BUGS
Report bugs to <http://sf.net/bugs/?group_id=3331>. COPYRIGHT
Copyright (C) 1995-2010 Charlie Zender This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU- LAR PURPOSE. SEE ALSO
The 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. HOMEPAGE
The NCO homepage at <http://nco.sf.net> contains more information. NCRA(1)