netcdfWriter Configuration

The netcdfWriterConfig gives the opportunity to set some features explicit only for netcdf-files, i.e. file-format (netcdf3/4) or compression.

It is also possible to add an ncml Configuration to the output to change the internal structure just before writing.

It is also possible ot change units including all value in the netcdfWriterDoc. Changing the units in the ncmlConfiguration would change the attribute value only, but not the data.

The CDM resembles a netcdf datastructure. In general, there is no need to use a configuration for this writer, but it might be useful in the following cases:

Output-files are to big, and a change of datatype i.e. from float to short is desired
Different attributes are required for special usages, but the input-configuration of the reader shouldn't been changed.
Different variable- or dimension-names are required for special usages.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE cdm_ncwriter_config SYSTEM "cdmWriterConfig.dtd">
<cdm_ncwriter_config>

<!-- filetype are netcdf3 netcdf3_64bit netcdf4 netcdf4classic -->
<!-- compression levels are 0 (no compression) to 9 -->
<!-- compression levels from 10 to 19 will enable shuffling -->
<!-- <default filetype="netcdf4" compressionLevel="3" /> -->
<!-- <default filetype="netcdf3" compressionLevel="0" autoRemoveUnusedDimension="false" /> -->

<dimension name="x_c" chunkSize="4" />

<!--  change units from m to km-->
<!--  make sure to put the type to change the data, too!!! -->
<variable name="x_c" type="double">
   <attribute name="units" value="km" type="string" />
</variable>

<!-- change the compressionLevel of a netcdf4 variable -->
<variable name="precipitation_amout" compressionLevel="3"/>

<!-- configure the output with the help of ncml -->
<ncmlConfig  filename="../share/etc/ncmlCDMConfig.ncml" />

</cdm_ncwriter_config>

See also: MetNoFimex::GribApiCDMWriter