8.6.3.5 IfcDocumentReference
8.6.3.5.1 Semantic definition
An IfcDocumentReference is a reference to the location of a document. The reference is given by a system interpretable Location attribute (a URL string) where the document can be found, and an optional inherited internal reference Identification, which refers to a system interpretable position within the document. The optional inherited Name attribute is meant to have meaning for human readers. Optional document metadata can also be captured through reference to IfcDocumentInformation.
New entity in IFC2.08.6.3.5.2 Entity inheritance
8.6.3.5.3 Attributes
| # | Attribute | Type | Description |
|---|---|---|---|
| IfcExternalReference (4) | |||
| 1 | Location | OPTIONAL IfcURIReference |
Location, where the external source (classification, document or library) can be accessed by electronic means. The electronic location is provided as an URI, and would normally be given as an URL location string. The data type has been changed from IfcLabel to IfcURIReference . |
| 2 | Identification | OPTIONAL IfcIdentifier |
The Identification provides a unique identifier of the referenced item within the external source (classification, document or library). It may be provided as * a key, e.g. a classification notation, like NF2.3 * a handle * a uuid or guid It may be human readable (such as a key) or not (such as a handle or uuid) depending on the context of its usage (which has to be determined by local agreement). Attribute renamed from ItemReference for consistency. |
| 3 | Name | OPTIONAL IfcLabel |
Optional name to further specify the reference. It can provide a human readable identifier (which does not necessarily need to have a counterpart in the internal structure of the document). |
| ExternalReferenceForResources | SET [0:?] OF IfcExternalReferenceRelationship FOR RelatingReference |
Reference to all associations between this external reference and objects within the IfcResourceObjectSelect that are tagged by the external reference. New inverse attribute added with upward compatibility. |
|
| Click to show 4 hidden inherited attributes Click to hide 4 inherited attributes | |||
| IfcDocumentReference (3) | |||
| 4 | Description | OPTIONAL IfcText |
Description of the document reference for informational purposes. New attribute added at the end of the attribute list. |
| 5 | ReferencedDocument | OPTIONAL IfcDocumentInformation |
The document that is referenced. |
| DocumentRefForObjects | SET [0:?] OF IfcRelAssociatesDocument FOR RelatingDocument |
The document reference with which objects are associated. New inverse attribute. |
|
8.6.3.5.4 Formal propositions
| Name | Description |
|---|---|
| WR1 |
A name should only be given, if no document information (including the document name) is attached |
|
|
8.6.3.5.5 Examples
8.6.3.5.6 Formal representation
ENTITY IfcDocumentReference
SUBTYPE OF (IfcExternalReference);
Description : OPTIONAL IfcText;
ReferencedDocument : OPTIONAL IfcDocumentInformation;
INVERSE
DocumentRefForObjects : SET [0:?] OF IfcRelAssociatesDocument FOR RelatingDocument;
WHERE
WR1 : EXISTS(Name) XOR EXISTS(ReferencedDocument);
END_ENTITY;