HDF5 documents and links 
Introduction to HDF5 
HDF5 User Guide 
And in this document, the HDF5 Reference Manual  
H5   H5A   H5D   H5E   H5F   H5G   H5I   H5P  
H5R   H5S   H5T   H5Z   Tools   Datatypes  
(PDF of complete manual formatted as print volume)   

H5G: Group Interface

Group Object API Functions

The Group interface functions create and manipulate groups of objects in an HDF5 file.

The C Interfaces:
             
Alphabetical Listing
             

The FORTRAN90 Interfaces:
In general, each FORTRAN90 subroutine performs exactly the same task as the corresponding C function.
             

A group associates names with objects and provides a mechanism for mapping a name to an object. Since all objects appear in at least one group (with the possible exception of the root object) and since objects can have names in more than one group, the set of all objects in an HDF5 file is a directed graph. The internal nodes (nodes with out-degree greater than zero) must be groups while the leaf nodes (nodes with out-degree zero) are either empty groups or objects of some other type. Exactly one object in every non-empty file is the root object. The root object always has a positive in-degree because it is pointed to by the file super block.

An object name consists of one or more components separated from one another by slashes. An absolute name begins with a slash and the object is located by looking for the first component in the root object, then looking for the second component in the first object, etc., until the entire name is traversed. A relative name does not begin with a slash and the traversal begins at the location specified by the create or access function.


HDF5 documents and links 
Introduction to HDF5 
HDF5 User Guide 
And in this document, the HDF5 Reference Manual  
H5   H5A   H5D   H5E   H5F   H5G   H5I   H5P  
H5R   H5S   H5T   H5Z   Tools   Datatypes  
(PDF of complete manual formatted as print volume)   

The HDF Group Help Desk:
Describes HDF5 Release 1.6.10, November 2009