Definition from IAI: An IfcClassificationNotation is a
notation used from published reference (which may be either publicly available
from a classification society or is published locally for the purposes of an
organization, project or other purpose).
Note: A classification notation may be developed using
various notation facets. A facet is a part of the actual notation but which has
a specific meaning. For instance, it may be appropriate to classify an item by
owning actor (represented by A=Architect) and by an entry from a classification
table such as CI/SfB (represented by 210 for external wall). This gives a
classification as A210
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
All classifications of an object that are contained within the IFC model
are made through the IfcClassificationNotation class (and not through
IfcClassification as was the case up to R2.0). For a given object, the
IfcRelAssociatesClassification class (contained within the IfcKernel) makes the
connection between the IfcObject (abstract superclass, IfcDoor has been taken
as an example for instantiation) and the IfcClassificationNotation. IfcObject
<-- IfcRelAssociatesClassification --> IfcClassificationNotation.
Consider an object that is to be classified with the notation "L6814". In this
case, the IfcRelAssociatesClassification has the form:
-
#100 IFCDOOR (.....);
-
#200 IFCCLASSIFICATIONNOTATIONFACET ('L6814');
-
#300 IFCCLASSIFICATIONNOTATION ((#200));
-
#400 IFCRELASSOCIATESCLASSIFICATION ((#300),#100);
If the object is to have other notations (e.g. B2186 and Z6793), the
IfcRelAssociatesClassification has the form:
-
#100 IFCDOOR (.....);
-
#200 IFCCLASSIFICATIONNOTATIONFACET ('L6814');
-
#210 IFCCLASSIFICATIONNOTATIONFACET ('B2186');
-
#220 IFCCLASSIFICATIONNOTATIONFACET ('Z6793');
-
#300 IFCCLASSIFICATIONNOTATION ((#200,#210,#220));
-
#400 IFCRELASSOCIATESCLASSIFICATION ((#300),#100);
It is a requirement that a classification notation can only bring
together facets from the same classification system or source. Bringing
together notation facets from different sources within the same classification
notation is not allowed. However, since the IfcRelAssociatesClassification
class does allow for multiple classifications to a single object, then it is
possible to define multiple classification notations where each notation
contains facets from a single source.
-
#100 IFCDOOR (.....);
-
#200 IFCCLASSIFICATIONNOTATIONFACET ('L6814');
-
#210 IFCCLASSIFICATIONNOTATIONFACET ('B2186');
-
#220 IFCCLASSIFICATIONNOTATIONFACET ('Z6793');
-
#300 IFCCLASSIFICATIONNOTATIONFACET ('106');
-
#400 IFCCLASSIFICATIONNOTATIONFACET ('A-31-623');
-
#410 IFCCLASSIFICATIONNOTATIONFACET ('B-62-562');
-
#500 IFCCLASSIFICATIONNOTATION ((#200,#210,#220));
-
#510 IFCCLASSIFICATIONNOTATION ((#300));
-
#520 IFCCLASSIFICATIONNOTATION ((#400,#410));
-
#600 IFCRELASSOCIATESCLASSIFICATION (#100,(#500,#510,#520));
