8.17.3.7 IfcQuantityNumber
8.17.3.7.1 Semantic definition
IfcQuantityNumber is a physical quantity that defines a derived number measure (integer or non-integer) to provide an element's physical property. It is normally derived from the physical properties of the element under the specific measure rules given by a method of measurement.
8.17.3.7.2 Entity inheritance
8.17.3.7.3 Attributes
| # | Attribute | Type | Description | 
|---|---|---|---|
| IfcPhysicalQuantity (4) | |||
| 1 | Name | IfcLabel | 
 Name of the element quantity or measure. The name attribute has to be made recognizable by further agreements.  | 
| 2 | Description | OPTIONAL IfcText | 
 Further explanation that might be given to the quantity.  | 
| HasExternalReferences | SET [0:?] OF IfcExternalReferenceRelationship FOR RelatedResourceObjects | 
 Reference to an external reference, e.g. library, classification, or document information, that is associated to the quantity.  | 
|
| PartOfComplex | SET [0:1] OF IfcPhysicalComplexQuantity FOR HasQuantities | 
 Reference to a physical complex quantity in which the physical quantity may be contained.  | 
|
| IfcPhysicalSimpleQuantity (1) | |||
| 3 | Unit | OPTIONAL IfcNamedUnit | 
 Optional assignment of a unit. If no unit is given, then the global unit assignment, as established at the IfcProject, applies to the quantity measures.  | 
| Click to show 5 hidden inherited attributes Click to hide 5 inherited attributes | |||
| IfcQuantityNumber (2) | |||
| 4 | NumberValue | IfcNumericMeasure | 
 Count measure value of this quantity.  | 
| 5 | Formula | OPTIONAL IfcLabel | 
 A formula by which the quantity has been calculated. It can be assigned in addition to the actual value of the quantity. Formulas could be mathematic calculations (like width x height), database links, or a combination. The formula is for informational purposes only.  | 
8.17.3.7.4 Formal representation
ENTITY IfcQuantityNumber
 SUBTYPE OF (IfcPhysicalSimpleQuantity);
	NumberValue : IfcNumericMeasure;
	Formula : OPTIONAL IfcLabel;
END_ENTITY;