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[netCDF #NKM-158888]: compression with netcdf

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  • Subject: [netCDF #NKM-158888]: compression with netcdf
  • Date: Tue, 05 Sep 2023 17:29:51 -0600
Hello,

The szlib is read-only, so you can use it to read data, but unfortunately you 
cannot use it when compressing new data or copying data via `nccopy`.  I'm 
sorry I couldn't provide an answer in the affirmative, but I hope this 
information helps,

-Ward

> Hello,
> I have a question relating to on the fly compression on variables. If I 
> understood it correctly on the fly compression is possible by using the 
> "nc_def_var_deflate" function. As far as I understand it this uses the 
> deflate algorithm, i.e. zlib? Is it also possible to use szlib for on the fly 
> compression? If so, which function would I call then?
> 
> A similar question if I do compression on a file and use nccopy with -d.... 
> am I correct to assume that this also uses the zlib deflate algorithm? How 
> could I switch to sz for this?
> 
> I am using the following build of netcdf:
> 
> This netCDF 4.9.2 has been built with the following features:
> 
> --static        -> -lhdf5_hl -lhdf5 -lm -lz -ldl -lzip -lsz -lbz2 -lzstd 
> -lblosc
> --has-dap          -> no
> --has-dap2         -> no
> --has-dap4         -> no
> --has-nc2          -> yes
> --has-nc4          -> yes
> --has-hdf5         -> yes
> --has-hdf4         -> no
> --has-logging      -> no
> --has-pnetcdf      -> no
> --has-szlib        -> yes
> --has-cdf5         -> yes
> --has-parallel4    -> no
> --has-parallel     -> no
> --has-nczarr       -> yes
> --has-zstd         -> yes
> --has-benchmarks   -> no
> --has-multifilters -> yes
> --has-stdfilters   -> deflate bz2 blosc zstd
> --has-quantize     -> yes
> 
> Thank you
> Stefanie Reuter
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: NKM-158888
Department: Support netCDF
Priority: Normal
Status: Closed
===================
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