IfcPropertyBoundedValue

Semantic definitions at the entity

Entity definition

A property with a bounded value, IfcPropertyBoundedValue, defines a property object which has a maximum of two (numeric or descriptive) values assigned, the first value specifying the upper bound and the second value specifying the lower bound. It defines a property - value bound (min-max) combination for which the property Name, an optional Description, the optional UpperBoundValue with measure type, the optional LowerBoundValue with measure type, and the optional Unit is given. A set point value can be provided in addition to the upper and lower bound values for operational value setting.

The unit is handled by the Unit attribute, see Table 768 for an example of a bounded property:

If the Unit attribute is not given, then the unit is already implied by the type of IfcMeasureValue or IfcDerivedMeasureValue. The associated unit can be found at the IfcUnitAssignment globally defined at the project level (IfcProject.UnitsInContext).
If the Unit attribute is given, then the unit assigned by the Unit attribute overrides the globally assigned unit.

The IfcPropertyBoundedValue allows for the specification of an interval for the value component of the property description. If either the LowerBoundValue or the UpperBoundValue is not given, then it indicates an open bound (either a minimum value or a maximum value). The interval is by definition inclusive, that is, the value given for the LowerBoundValue or the UpperBoundValue is included in the interval.

NOTE An IfcPropertyBoundedValue may be exchanged with no values assigned yet. In this case the LowerBoundValue and the UpperBoundValue are set to NIL.

Name	UpperBoundValue	LowerBoundValue	SetPointValue	Type (through IfcValue)	Unit
OverallHeight	1930	2300	<nil>	IfcPositiveLengthMeasure	-
OverallWidth	0.9	1.25	<nil>	IfcPositiveLengthMeasure	m
MaxHeight	20.0	<nil>	<nil>	IfcPositiveLengthMeasure	-
MinWeight	<nil>	20	<nil>	IfcMassMeasure	kg
* Where rules ensures same measure type for all values

Table 768 — Bounded property with values, measure types and units

HISTORY New entity in IFC2x.

IFC2x2 CHANGE The attribute type of the attribute UpperBoundValue and LowerBoundValue has been made optional with upward compatibility for file based exchange.

IFC4 CHANGE The attribute SetPointValue has been added.

Informal Propositions:

If the measure type for the upper and lover bound value is a numeric measure, then the following shall be true: UpperBoundValue > LowerBoundValue.

Attribute definitions

#	Attribute	Type	Cardinality	Description	G
3	UpperBoundValue	IfcValue	?	Upper bound value for the interval defining the property value. If the value is not given, it indicates an open bound (all values to be greater than or equal to LowerBoundValue).	X
4	LowerBoundValue	IfcValue	?	Lower bound value for the interval defining the property value. If the value is not given, it indicates an open bound (all values to be lower than or equal to UpperBoundValue).	X
5	Unit	IfcUnit	?	Unit for the upper and lower bound values, if not given, the default value for the measure type is used as defined by the global unit assignment at IfcProject.UnitInContext. The applicable unit is then selected by the underlying TYPE of the UpperBoundValue, LowerBoundValue, and SetPointValue)	X
6	SetPointValue	IfcValue	?	Set point value as typically used for operational value setting. IFC4 CHANGE The attribute has been added at the end of the attribute list.	X

Formal Propositions

Rule	Description
SameUnitUpperLower	The measure type of the UpperBoundValue shall be the same as the measure type of the LowerBoundValue, if both (upper and lower bound) are given.
SameUnitUpperSet	The measure type of the UpperBoundValue shall be the same as the measure type of the SetPointValue, if both (upper bound and set point) are given.
SameUnitLowerSet	The measure type of the LowerBoundValue shall be the same as the measure type of the SetPointValue, if both (lower bound and set point) are given.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	G
IfcPropertyAbstraction
	HasExternalReferences	IfcExternalReferenceRelationship @RelatedResourceObjects	S[0:?]	Reference to an external reference, e.g. library, classification, or document information, that is associated to the property definition. IFC4 CHANGE New inverse attribute.	X
IfcProperty
1	Name	IfcIdentifier		Name for this property. This label is the significant name string that defines the semantic meaning for the property.	X
2	Specification	IfcText	?	Informative text to explain the property.	X
	PartOfPset	IfcPropertySet @HasProperties	S[0:?]	Reference to the IfcPropertySet by which the IfcProperty is referenced. IFC4 CHANGE New inverse attribute to navigate from IfcProperty to IfcPropertySet with upward compatibility for file based exchange.	X
	PropertyForDependance	IfcPropertyDependencyRelationship @DependingProperty	S[0:?]	The property on whose value that of another property depends.	X
	PropertyDependsOn	IfcPropertyDependencyRelationship @DependantProperty	S[0:?]	The relating property on which the value of the property depends.	X
	PartOfComplex	IfcComplexProperty @HasProperties	S[0:?]	Reference to the IfcComplexProperty in which the IfcProperty is contained. IFC4 CHANGE The cardinality has changed to 0..n to allow reuse of instances of IfcProperty in several IfcComplexProperty with upward compatibility for file based exchange.	X
	HasConstraints	IfcResourceConstraintRelationship @RelatedResourceObjects	? S[0:?]	User-defined constraints for the property.	X
	HasApprovals	IfcResourceApprovalRelationship @RelatedResourceObjects	? S[0:?]	User-defined approvals for the property.	X
	PartOfMaterialOrProfileProperties	IfcExtendedProperties @Properties	S[0:?]	Reference to the IfcMaterialProperties by which the IfcProperty is referenced.	X
IfcSimpleProperty
IfcPropertyBoundedValue
3	UpperBoundValue	IfcValue	?	Upper bound value for the interval defining the property value. If the value is not given, it indicates an open bound (all values to be greater than or equal to LowerBoundValue).	X
4	LowerBoundValue	IfcValue	?	Lower bound value for the interval defining the property value. If the value is not given, it indicates an open bound (all values to be lower than or equal to UpperBoundValue).	X
5	Unit	IfcUnit	?	Unit for the upper and lower bound values, if not given, the default value for the measure type is used as defined by the global unit assignment at IfcProject.UnitInContext. The applicable unit is then selected by the underlying TYPE of the UpperBoundValue, LowerBoundValue, and SetPointValue)	X
6	SetPointValue	IfcValue	?	Set point value as typically used for operational value setting. IFC4 CHANGE The attribute has been added at the end of the attribute list.	X

Formal representations

XML Specification

 <xs:element name="IfcPropertyBoundedValue" type="ifc:IfcPropertyBoundedValue" substitutionGroup="ifc:IfcSimpleProperty" nillable="true"/>

 <xs:complexType name="IfcPropertyBoundedValue">

  <xs:complexContent>

   <xs:extension base="ifc:IfcSimpleProperty">

    <xs:sequence>

     <xs:element name="UpperBoundValue" nillable="true" minOccurs="0">

      <xs:complexType>

       <xs:group ref="ifc:IfcValue"/>

      </xs:complexType>

     </xs:element>

     <xs:element name="LowerBoundValue" nillable="true" minOccurs="0">

      <xs:complexType>

       <xs:group ref="ifc:IfcValue"/>

      </xs:complexType>

     </xs:element>

     <xs:element name="Unit" nillable="true" minOccurs="0">

      <xs:complexType>

       <xs:group ref="ifc:IfcUnit"/>

      </xs:complexType>

     </xs:element>

     <xs:element name="SetPointValue" nillable="true" minOccurs="0">

      <xs:complexType>

       <xs:group ref="ifc:IfcValue"/>

      </xs:complexType>

     </xs:element>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcPropertyBoundedValue

 SUBTYPE OF (IfcSimpleProperty);

  UpperBoundValue : OPTIONAL IfcValue;

  LowerBoundValue : OPTIONAL IfcValue;

  Unit : OPTIONAL IfcUnit;

  SetPointValue : OPTIONAL IfcValue;

 WHERE

  SameUnitUpperLower : NOT(EXISTS(UpperBoundValue)) OR NOT(EXISTS(LowerBoundValue)) OR

(TYPEOF(UpperBoundValue) = TYPEOF(LowerBoundValue));
  SameUnitUpperSet : NOT(EXISTS(UpperBoundValue)) OR NOT(EXISTS(SetPointValue)) OR

(TYPEOF(UpperBoundValue) = TYPEOF(SetPointValue));
  SameUnitLowerSet : NOT(EXISTS(LowerBoundValue)) OR NOT(EXISTS(SetPointValue)) OR

(TYPEOF(LowerBoundValue) = TYPEOF(SetPointValue));
END_ENTITY;

 EXPRESS-G diagram

Item	SPF	XML	Change	Description
IFC2x3 to IFC4 4.0.0.0
IfcPropertyBoundedValue
SetPointValue			ADDED
IFC4 Addendum 1 4.0.1.0
IfcPropertyBoundedValue
HasConstraints			ADDED
HasApprovals			ADDED
IFC4X3_ADD2 to IFC4X4_draft
IfcPropertyBoundedValue
PartOfMaterialOrProfileProperties			ADDED

	Merkmal mit Grenzwerten
	Property Bounded Value
	Propriété à valeur bornée