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cdflib.getCompression

Compression settings

Syntax

[ctype,cparms,cpercentage] = cdflib.getCompression(cdfId)

Description

[ctype,cparms,cpercentage] = cdflib.getCompression(cdfId) returns information about the compression settings of a Common Data Format (CDF) file.

Input Arguments

cdfId

Identifier of a CDF file, returned by a call to cdflib.create or cdflib.open.

Output Arguments

ctype

Character vector specifying compression type, such as 'HUFF_COMPRESSION'. If the CDF does not use compression, the function returns 'NO_COMPRESSION'. For a list of supported compression types, see cdflib.setCompression.

cparms

The value of the parameter associated with the type of compression. For example, for the 'RLE_COMPRESSION' compression type, the parameter specifies the style of run-length encoding. For a list of parameters supported by each compression type, see cdflib.setCompression.

cpercentage

The rate of compression, expressed as a percentage.

Examples

Open the example CDF file and check the compression settings in the file.

cdfId = cdflib.open("example.cdf");

[ctype,cparms,cpercentage] = cdflib.getCompression(cdfId)
ctype =

    'GZIP_COMPRESSION'


cparms =

     7


cpercentage =

    26
% Clean up
cdflib.close(cdfId)
clear cdfId

References

This function corresponds to the CDF library C API routine CDFgetCompression.

To use this function, you must be familiar with the CDF C interface. You can access the CDF documentation at the CDF website.