# Metadata extensions for describing the internal structure of a data set
#
# Peter N. Schweitzer (U.S. Geological Survey, Reston VA 20192)

Extension_Information:
	Extended_Element_Name: Data_Set_Structure
	Short_Name: dsstruct
	Parent: Identification_Information
	Child: Data_Set_Part
	Type: Compound
	Optionality: Optional
	Repeatability: Repeatable
	Definition: Description of the data set as a set of parts
	Rationale:
		Within scientific disciplines, data sets are often composed
		of several distinct digital files or sets of files, each
		containing information about some aspect of the work.
		In the CSDGM, Format_Information_Content is available for
		describing the contents of any portion of the data set for
		which one can specify a Digital_Transfer_Option.  However
		using the standard elements to provide a "table of contents"
		of the data set incurs substantial overhead and implies,
		perhaps falsely, that each part of a data set can be obtained
		independently either online or offline.  Further, there is
		no standard element to indicate a name for the part, nor to
		distinguish parts with the same format but different contents.
	Source: Peter N. Schweitzer (U.S. Geological Survey, Reston VA 20192)
	Rule: Data_Set_Structure = (1{Data_Set_Part}n)

Extension_Information:
	Extended_Element_Name: Data_Set_Part
	Short_Name: dspart
	Type: Compound
	Parent: Data_Set_Structure
	Child: Part_Type
	Child: Part_Name
	Child: Part_Description
	Child: Data_Set_Part
	Optionality: Optional
	Repeatability: Repeatable
	Definition: One of a set of parts of the data set
	Rationale:
		This element specifies the relationship between the name, type,
		and description of each of the parts of the data set.
	Source: Peter N. Schweitzer (U.S. Geological Survey, Reston VA 20192)
	Rule: Data_Set_Part = Part_Type + Part_Name + Part_Description

Extension_Information:
	Extended_Element_Name: Part_Type
	Short_Name: dspttype
	Type: text
	Parent: Data_Set_Part
	Optionality: Mandatory
	Repeatability: Not Repeatable
	Definition:
		The general class (of parts of data sets) into which this part
		falls.  Examples are "File", "Coverage", "Table", "Directory".
	Rationale:
		Data transfer formats may partition information in various ways.
		The simplest use of this element would be to specify a digital
		file or directory, but it could be used to specify a part of a
		composite file, as in HDF.  For example, the AVHRR data
		created by PO.DAAC at JPL, may contain images and gridded
		data quality information in the same file.
	Source: Peter N. Schweitzer (U.S. Geological Survey, Reston VA 20192)

Extension_Information:
	Extended_Element_Name: Part_Name
	Short_Name: dsptname
	Type: text
	Parent: Data_Set_Part
	Optionality: Mandatory
	Repeatability: Not repeatable
	Definition:
		The name of this part of the data set.  The interpretation
		of this value depends on the corresponding Part_Type.  For
		example, if Part_Type is "File" then Part_Name is likely a
		file specification.  If Part_Type is "Coverage" then Part_Name
		is either a directory specification or the name of an export
		file.
	Rationale:
		No standard element is explicitly intended to specify the name
		of one digital file among many that compose a data set, except
		for Browse_Graphic_File_Name, and nothing in the standard implies
		or requires that the file named in that element be part of the
		data set as transferred.
	Source: Peter N. Schweitzer (U.S. Geological Survey, Reston VA 20192)

Extension_Information:
	Extended_Element_Name: Part_Description
	Short_Name: dsptdesc
	Type: text
	Parent: Data_Set_Part
	Optionality: Mandatory
	Repeatability: Not repeatable
	Definition:
		A narrative explaining the contents of this part of the data set.
	Rationale:
		This element provides a mechanism for describing in plain
		language the contents of a specific file found in a data set.
	Source: Peter N. Schweitzer (U.S. Geological Survey, Reston VA 20192)

# (end)