IfcQuantityArea

Definition from IAI: A physical quantity, IfcQuantityArea, that defines a derived area measure 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.

> EXAMPLE: An opening may have an opening area used to deduct it from the wall surface area. The actual size of the area depends on the method of measurement used.

> HISTORY New entity in IFC Release 2.x. It replaces the calcXxx attributes used in previous IFC Releases.

EXPRESS specification:

ENTITY IfcQuantityArea
SUBTYPE OF ( | IfcPhysicalSimpleQuantity);
AreaValue | : | IfcAreaMeasure;
WHERE
WR21 | : | NOT(EXISTS(SELF\IfcPhysicalSimpleQuantity.Unit)) OR (SELF\IfcPhysicalSimpleQuantity.Unit.UnitType = IfcUnitEnum.AREAUNIT);
WR22 | : | AreaValue >= 0.;
END_ENTITY;

Attribute definitions:

AreaValue | : | Area measure value of this quantity.

Formal Propositions:

WR21 | : | If a unit is given, the unit type shall be area unit.
WR22 | : | A valid area quantity shall be greater than or equal to zero.

Inheritance graph

ENTITY IfcQuantityArea;
ENTITY IfcPhysicalQuantity;
Name | : | IfcLabel;
Description | : | OPTIONAL IfcText;
INVERSE
PartOfComplex | : | SET [0:1] OF IfcPhysicalComplexQuantity FOR HasQuantities;
ENTITY IfcPhysicalSimpleQuantity;
Unit | : | OPTIONAL IfcNamedUnit;
ENTITY IfcQuantityArea;
AreaValue | : | IfcAreaMeasure;
END_ENTITY;