This entity captures a value driven by a formula, with additional qualifications including unit basis, valid date range, and categorization.

The extent of the IfcAppliedValue is determined by the AppliedValue attribute which may be defined either as an IfcMeasureWithUnit or as an IfcMonetaryMeasure or as an IfcRatioMeasure via the IfcAppliedValueSelect type.

Optionally, an IfcAppliedValue may have an applicable date. This is intended to fix the date on which the value became relevant for use. It may be the date on which the value was set in the model or it may be a prior or future date when the value becomes operable. Similarly, an IfcAppliedValue may have a 'fixed until' date. This is intended to fix the date on which the value ceases to be relevant for use.

An instance of IfcAppliedValue may have a unit basis asserted. This is defined as an IfcMeasureWithUnit that determines the extent of the unit value for application purposes. It is assumed that when this attribute is asserted, then the value given to IfcAppliedValue is that for unit quantity. This is not enforced within the schema and thus needs to be controlled within an application.

Applied values may be referenced from a document (such as a price list). The relationship between one or more occurrences of IfcAppliedValue (or its subtypes) is achieved through the use of the IfcExternalReferenceRelationship in which the document provides the IfcExternalReferenceRelationship.RelatingExtReference and the value occurrences are the IfcExternalReferenceRelationship.RelatedResourceObjects.

HISTORY  New entity in IFC2x2.

IFC4 CHANGE  Entity made non-abstract to support general formula expressions of constraints, data type of date-based attributes changed into IfcDate, ValueType and Condition promoted from IfcCostValue, Components and ArithmeticOperator attributes added to replace IfcAppliedValueRelationship for more efficient encoding and reference tracking.