ncpdq man page

ncpdq — netCDF Permute Dimensions Quickly, Pack Data Quietly...


ncpdq [-3] [-4] [-6] [-7] [-A] [-a dim[,...]] [--bfr sz_byt][-C][-c][--cnk_byt sz_byt][--cnk_dmn nm,sz_lmn] [--cnk_map map] [--cnk_min sz_byt] [--cnk_plc plc] [--cnk_scl sz_lmn][-D dbg_lvl] [-d dim,[ min][,[ max]]] [-F] [-G gpe_dsc] [-g grp[,...]] [--glb att_name= att_val]] [-h] [--hdf] [--hdr_pad sz_byt] [-L dfl_lvl] [-l path] [-M pck_map] [--mrd] [--msa] [--no_tmp_fl] [-O] [-o output-file] [-P pck_plc] [-p path] [--ppc var1[, var2[,...]]= prc]] [-R] [-r] [--ram_all] [-t thr_nbr] [-U] [--unn] [-v var[,...]] [-X box] [-x] input-file [ output-file ]


ncpdq packs or re-shapes variables in input-file and stores them in output-file. Which variables to pack/unpack are determined by the packing policy encoded in the pck_plc argument to the -P switch. Valid pck_plc options are all_new, all_xst, xst_new, and upk. The numeric type of variable to pack or re-pack a variable to is determined by the packing map encoded in the pck_map argument to the -M switch. Valid pck_map options are flt_byt, flt_sht, hgh_byt, hgh_sht, and nxt_lsr.

ncpdq re-shapes variables in input-file by re-ordering and/or reversing dimensions specified in the dimension list. The dimension list is a comma separated list of dimension names, optionally prefixed by negative signs, that follow the -a switch. To re-order variables by a subset of their dimensions, specify these dimensions in a comma-separated list following -a, e.g., -a lon,lat. To reverse a dimension, prefix its name with a negative sign in the dimension list, e.g., -a -lat. Re-ordering and reversal may be performed simultaneously, e.g., -a lon,-lat,time,-lev.

Users may specify any permutation of dimensions, including permutations which change the record dimension identity. The record dimension is re-ordered like any other dimension. The record dimension is always the most slowly varying dimension in a record variable. The specified re-ordering will fail if it requires creating more than one record dimension amongst all the output variables.


NCO manual pages written by Charlie Zender and originally formatted by Brian Mays.

Reporting Bugs

Report bugs to <>.

See Also

The full documentation for NCO is maintained as a Texinfo manual called the NCO Users 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 Users Guide are the PDF (recommended), DVI, and Postscript versions at <>, <>, and <>, respectively. HTML and XML versions are available at <> and <>, 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.

ncap(1), ncap2(1), ncatted(1), ncbo(1), ncclimo(1), nces(1), ncecat(1), ncflint(1), ncks(1), nco(1), ncpdq(1), ncra(1), ncrcat(1), ncremap(1), ncrename(1), ncwa(1)


The NCO homepage at <> contains more information.

Referenced By

ncap(1), ncap2(1), ncatted(1), ncclimo(1), ncecat(1), nces(1), ncflint(1), ncks(1), nco(1), ncra(1), ncrcat(1), ncremap(1), ncrename(1), ncwa(1).