IfcClassification

IfcClassification

Definition from IAI: An IfcClassification is used for the arrangement of objects into a class or category according to a common purpose or their possession of common characteristics.

HISTORY: New class in IFC Release 1.5. It has changed in IFC Release 2x.

ISSUES: See issue and change log for changes made in IFC Release 2x.

Use Definitions

In previous releases of IFC, the IfcClassification class was used as the means for connecting classifications to objects. This is no longer the case for IFC Release 2x, the IfcClassificationNotation Class having taken on this role. IfcClassification is now used to identfy the classification system or source from which a classification notation is derived. The objective is to minimize the number of IfcClassification objects contained within an IFC model. Ideally, each classification system or source used should have only one IfcClassification object. However, because multiple classification is allowed, there may be many IfcClassification objects used, each identifying a different classification system or source. An example of the use of the IfcClassification class is:

#1 IFCCALENDARDATE (31,8,1997);

#2 IFCCLASSIFICATION(‘RIBA’,’1’,#1,’Uniclass’)

EXPRESS specification:

ENTITY IfcClassification;

Source

IfcLabel;

Edition

IfcLabel;

EditionDate

OPTIONAL IfcCalendarDate;

Name

IfcLabel;

INVERSE

Contains

SET OF IfcClassificationItem FOR ItemOf;

END_ENTITY;

Attribute definitions:

Source	:	Source (or publisher) for this classification.
Edition	:	The edition or version of the classification system from which the classification notation is derived.
EditionDate	:	The date on which the edition of the classification used became valid. NOTE: The indication of edition may be sufficient to identify the classification source uniquely but the edition date is provided as an optional attribute to enable more precise identification where required.
Name	:	The name or label by which the classification used is normally known. NOTE: Examples of names include CI/SfB, Masterformat, BSAB, Uniclass, STABU etc.