[netcdfgroup] Ann: NCL/PyNIO now have support for netCDF-4 classic format

[Jeff Whitaker]

Mary Haley wrote:
> Hi all,
>
> This is a bit of a late announcement, but NCL V4.3.1 and PyNIO V1.2.0
> have support built-in for reading and writing netCDF-4 classic files
> on systems where netcdf-4.0-beta1 is supported.
>
> With NCL, you can write a netCDF-4 classic file by calling the
> "setfileoption" procedure with the "format" option before you call
> "addfile" to create a netCDF-4 classic 4 file:
>
>    setfileoption("nc","format","netcdf4classic")
>    a = addfile("file.nc","c")
>
> You can further specify a compression level:
>
>    setfileoption("nc","compressionlevel",5)
>
> Similar code exists for PyNIO:
>
> import Nio
> opt                  = Nio.options()
> opt.Format           = "netcdf4classic"
> opt.CompressionLevel = 5
>
> fout = Nio.open_file("file.nc","c",opt)
>
> For more information, see the NCL "setfileoption" or PyNIO documentation:
>
>    http://www.ncl.ucar.edu/Document/Functions/Built-in/setfileoption.shtml
>    http://www.pyngl.ucar.edu/Nio.shtml
>
> For download:
>
>     http://www.ncl.ucar.edu/Download/
>     http://www.pyngl.ucar.edu/download.shtml
>
> Cheers,
>
> --Mary
>
>   

Mary:  Can you turn the shuffle filter on with setfileoption?  I've 
found that it can really improve the compression ratios when used in 
conjunction with zlib compression in netcdf-4 files.

-Jeff

-- 
Jeffrey S. Whitaker         Phone  : (303)497-6313
Meteorologist               FAX    : (303)497-6449
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