IFC 4.3.x development

8.4.3.3 IfcCurrencyRelationship

Change log

IFC4

modificationsattributes RateDateTime definition Changed from IfcDateAndTime to IfcDateTime
modificationsattributes RateDateTime is_optionalChanged from False to True

8.4.3.3.1 Semantic definitions at the entity

IfcCurrencyRelationship defines the rate of exchange that applies between two designated currencies at a particular time and as published by a particular source.

An IfcCurrencyRelationship is used where there may be a need to reference an IfcCostValue in one currency to an IfcCostValue in another currency. It takes account of fact that currency exchange rates may vary by requiring the recording the date and time of the currency exchange rate used and the source that publishes the rate. There may be many sources and there are different strategies for currency conversion (spot rate, forward buying of currency at a fixed rate).

The source for the currency exchange is defined as an instance of IfcLibraryInformation that includes a name and a URL.

HISTORY  New entity in IFC2x2.

IFC4 CHANGE  Subtyped from IfcResourceLevelRelationship, attribute order changed.

8.4.3.3.1 Attributes

#Attribute Type Description
IfcResourceLevelRelationship
1Name OPTIONAL IfcLabel A name used to identify or qualify the relationship.
2Description OPTIONAL IfcText A description that may apply additional information about the relationship.
IfcCurrencyRelationship
3RelatingMonetaryUnitIfcMonetaryUnit The monetary unit from which an exchange is derived. For instance, in the case of a conversion from GBP to USD, the relating monetary unit is GBP.
4RelatedMonetaryUnit IfcMonetaryUnit The monetary unit to which an exchange results. For instance, in the case of a conversion from GBP to USD, the related monetary unit is USD.
5ExchangeRate IfcPositiveRatioMeasure The currently agreed ratio of the amount of a related monetary unit that is equivalent to a unit amount of the relating monetary unit in a currency relationship. For instance, in the case of a conversion from GBP to USD, the value of the exchange rate may be 1.486 (USD) : 1 (GBP).
6RateDateTime OPTIONAL IfcDateTime The date and time at which an exchange rate applies.

> IFC4 CHANGE Type changed from IfcDateTimeSelect. Attribute made optional.
7RateSource OPTIONAL IfcLibraryInformationThe source from which an exchange rate is obtained.

8.4.3.3.2 Entity inheritance

dot_inheritance IfcCurrencyRelationship IfcCurrencyRelationship IfcResourceLevelRelationship IfcResourceLevelRelationship IfcCurrencyRelationship->IfcResourceLevelRelationship IfcResourceLevelRelationship_children 8 more... IfcResourceLevelRelationship_children->IfcResourceLevelRelationship

8.4.3.3.3 Formal representations

ENTITY IfcCurrencyRelationship
 SUBTYPE OF (IfcResourceLevelRelationship);
	RelatingMonetaryUnit : IfcMonetaryUnit;
	RelatedMonetaryUnit : IfcMonetaryUnit;
	ExchangeRate : IfcPositiveRatioMeasure;
	RateDateTime : OPTIONAL IfcDateTime;
	RateSource : OPTIONAL IfcLibraryInformation;
END_ENTITY;