NAME

       nc3tonc4 - a program to convert netCDF 3 files to netCDF 4 format files

SYNOPSIS

       nc3tonc4    [-h]    [-o]    [--vars=var1,var2,..]     [--zlib=(0|1)]   [--complevel=(1-9)]
       [--shuffle=(0|1)]                [--fletcher32=(0|1)]                [--unpackshort=(0|1)]
       [--quantize=var1=n1,var2=n2,..]  netcdf3filename netcdf4filename

DESCRIPTION

       This manual page documents briefly the nc3tonc4 command.

       nc3tonc4  is  a  program  that  converts  a netCDF 3 file into netCDF 4 format, optionally
       unpacking variables packed as short integers (with scale_factor and add_offset) to floats,
       and  adding  zlib compression (with the HDF5 shuffle filter and fletcher32 checksum). Data
       may also be quantized (truncated) to a specified precision to improve compression.

OPTIONS

       These programs follow the usual GNU command line syntax, with long options  starting  with
       two dashes (`-').  A summary of options is included below.

       -h     Shows a summary of the available options.

       -o     Overwite  destination  file  (default  is  to raise an error if output file already
              exists).

       --vars A comma separated  list  of  variable  names  to  copy  (default  is  to  copy  all
              variables).

       --classic=(0|1)
              Use NETCDF4_CLASSIC format instead of NETCDF4 (default = 1).

       --zlib=(0|1)
              Activate (or disable) zlib compression (the default is to activate).

       --complevel=(1-9)
              Set the zlib compression level (6 is default).

       --shuffle=(0|1)
              Activate (or disable) the shuffle filter (it is active by default).

       --fletcher32=(0|1)
              Activate (or disable) the fletcher32 checksum (it is not active by default).

       --unpackshort=(0|1)
              Unpack short integer variables to float variables using scale_factor and add_offset
              netCDF variable attributes (it is active by default).

       --quantize=(comma separated list of variable name=integer pairs)
              Truncate the data in the specified variables to  a  given  decimal  precision.  For
              example,  'speed=2,  height=-2,  temp=0'  will  cause  the  variable  'speed' to be
              truncated to a precision of 0.01, 'height' to a precision of 100 and 'temp'  to  1.
              This  can  significantly improve compression. The default is not to quantize any of
              the variables.

       --quiet=(0|1)
              If set to 1, don't print any diagnostic information.

       --chunk=(integer)
              The number of records along unlimited dimension to write at once.  The  default  is
              10.  It  is  ignored if there is no unlimited dimension. If chunk=0, it means write
              all the data at once.

       --istart=(integer)
              The number of the record to start at along unlimited dimension. The default  is  0.
              This option is ignored if there is no unlimited dimension.

       --istop=(integer)
              The  number  of  the record to stop at along unlimited dimension. The default is 1.
              This option is ignored if there is no unlimited dimension.

SEE ALSO

       ncinfo(1), nc4tonc3(1).

AUTHOR

       This manual page was written by Ross Gammon  <rossgammon@mail.dk>  based  on  the  options
       displayed by nc3tonc4 -h.

                                           22 Mar 2015                                NC3TONC4(1)