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About HDF4 and HDF-EOS

Hierarchical Data Format (HDF4) is a general-purpose, machine-independent standard for storing scientific data in files, developed by the National Center for Supercomputing Applications (NCSA). For more information about these file formats, read the HDF documentation at the HDF Web site (

HDF-EOS is an extension of HDF4 that was developed by the National Aeronautics and Space Administration (NASA) for storage of data returned from the Earth Observing System (EOS). For more information about this extension to HDF4, see the HDF-EOS documentation at the NASA Web site (

HDF4 Application Programming Interfaces (APIs) are libraries of C routines. To import or export data, you must use the functions in the HDF4 API associated with the particular HDF4 data type you are working with. Each API has a particular programming model, that is, a prescribed way to use the routines to write data sets to the file. MATLAB® functions allow you to access specific HDF4 APIs.

To use the MATLAB HDF4 functions effectively, you must be familiar with the HDF library. For detailed information about HDF4 features and routines, refer to the documentation at the HDF Web site.