Crystallographic Information Framework

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Index

DDLm dictionary version 3.14.0

_type.purpose

Name:
_type.purpose

Definition:

   
     The primary purpose or function the defined data item serves in a
     dictionary or a specific data instance.

Type: Code


The data value must be one of the following:


Import
>>> Applied ONLY in the DDLm Reference Dictionary <<< Used to type the SPECIAL attribute "_import.get" that is present in dictionaries to instigate the importation of external dictionary definitions.

Method
>>> Applied ONLY in the DDLm Reference Dictionary <<< Used to type the attribute "_method.expression" that is present in dictionary definitions to provide the text method expressing the defined item in terms of other defined items.

Audit
>>> Applied ONLY in the DDLm Reference Dictionary <<< Used to type attributes employed to record the audit definition information (creation date, update version and cross reference codes) of items, categories and files.

Identify
>>> Applied ONLY in the DDLm Reference Dictionary <<< Used to type attributes that identify an item tag (or part thereof), save frame or the URI of an external file.

Extend
*** Used to EXTEND the DDLm Reference Dictionary *** Used in a definition, residing in the "extensions" save frame of a domain dictionary, to specify a new enumeration state using an Evaluation method.

Describe
Used to type items with values that are descriptive text intended for human interpretation.

Encode
Used to type items with values that are text or codes that are formatted to be machine parsable.

State
Used to type items with values that are restricted to codes present in their "enumeration_set.state" lists.

Key
Used to type an item with a value that is unique within the looped list of these items, and does not contain encoded information.

Link
Used to type an item that acts as a foreign key between two categories. The definition of the item must additionally contain the attribute "_name.linked_item_id" specifying the data name of the item with unique values in the linked category. The values of the defined item are drawn from the set of values in the referenced item. Cross referencing items from the same category is allowed.

Composite
Used to type items with value strings composed of separate parts. These will usually need to be separated and parsed for complete interpretation and application.

Number
Used to type items that are numerical and exact (i.e. no standard uncertainty value).

Measurand
Used to type an item with a numerically estimated value that has been recorded by measurement or derivation. This value must be accompanied by its standard uncertainty (SU) value, expressed either as: 1) appended integers, in parentheses (), at the precision of the trailing digits, or 2) a separately defined item with the same name as the measurand item but with an additional suffix '_su'.

SU
Used to type an item with a numerical value that is the standard uncertainty of another dataname. The definition of an SU item must include the attribute "_name.linked_item_id" which explicitly identifies the associated measurand item. SU values must be non-negative.

Internal
Used to type items that serve only internal purposes of the dictionary in which they appear. The particular purpose served is not defined by this state.

Enumeration default: Describe

Category:
type