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     Overwrite 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)