IfcObjective
实体定义
IfcObjective捕获基于目标的约束的定性信息。
IfcObjective是IfcConstraint的一个子类型，可以通过IfcControlExtension架构中的IfcRelAssociatesConstraint关系与IfcRoot的任何子类型相关联，也可以通过IfcResourceConstraintRelationship与IfcProperty相关联。
IfcObjective的目的是指定应用约束的目的，并获取约束的基准度量。
IFC2.0中的新实体。
IFC4 属性BenchmarkValues修改为IfcConstraint的LIST，属性ResultValues替换为IfcLogicalOperatorEnum。
Attribute definitions
| # | Attribute | Type | Cardinality | Description | C |
|---|---|---|---|---|---|
| 8 | BenchmarkValues | IfcConstraint | L[1:?] | A list of nested constraints. | X |
| 9 | LogicalAggregator | IfcLogicalOperatorEnum | [0:1] | Enumeration that identifies the logical type of aggregation for the benchmark metrics. | X |
| 10 | ObjectiveQualifier | IfcObjectiveEnum | [1:1] | Enumeration that qualifies the type of objective constraint. | X |
| 11 | UserDefinedQualifier | IfcLabel | [0:1] | A user defined value that qualifies the type of objective constraint when ObjectiveQualifier attribute of type IfcObjectiveEnum has value USERDEFINED. | X |
Formal Propositions
| Rule | Description |
|---|---|
| WR21 | The attribute UserDefinedQualifier must be asserted when the value of the ObjectiveQualifier is set to USERDEFINED. |
Attribute inheritance
| # | Attribute | Type | Cardinality | Description | C |
|---|---|---|---|---|---|
| IfcConstraint | |||||
| 1 | Name | IfcLabel | [1:1] | A human-readable name to be used for the constraint. | X |
| 2 | Description | IfcText | [0:1] | A human-readable description that may apply additional information about a constraint. | X |
| 3 | ConstraintGrade | IfcConstraintEnum | [1:1] | Enumeration that qualifies the type of constraint. | X |
| 4 | ConstraintSource | IfcLabel | [0:1] | Any source material, such as a code or standard, from which the constraint originated. | X |
| 5 | CreatingActor | IfcActorSelect | [0:1] | Person and/or organization that has created the constraint. | X |
| 6 | CreationTime | IfcDateTime | [0:1] | Time when information specifying the constraint instance was created. | X |
| 7 | UserDefinedGrade | IfcLabel | [0:1] | Allows for specification of user defined grade of the constraint beyond the enumeration values (hard, soft, advisory) provided by ConstraintGrade attribute of type IfcConstraintEnum. When a value is provided for attribute UserDefinedGrade in parallel the attribute ConstraintGrade shall have enumeration value USERDEFINED. | X |
| HasExternalReferences | IfcExternalReferenceRelationship @RelatedResourceObjects |
S[0:?] | Reference to an external references, e.g. library, classification, or document information, that are associated to the constraint. | X | |
| PropertiesForConstraint | IfcResourceConstraintRelationship @RelatingConstraint |
S[0:?] | Reference to the properties to which the constraint is applied. | X | |
| IfcObjective | |||||
| 8 | BenchmarkValues | IfcConstraint | L[1:?] | A list of nested constraints. | X |
| 9 | LogicalAggregator | IfcLogicalOperatorEnum | [0:1] | Enumeration that identifies the logical type of aggregation for the benchmark metrics. | X |
| 10 | ObjectiveQualifier | IfcObjectiveEnum | [1:1] | Enumeration that qualifies the type of objective constraint. | X |
| 11 | UserDefinedQualifier | IfcLabel | [0:1] | A user defined value that qualifies the type of objective constraint when ObjectiveQualifier attribute of type IfcObjectiveEnum has value USERDEFINED. | X |
EXPRESS Specification
ENTITY IfcObjective SUBTYPE OF (IfcConstraint); BenchmarkValues : OPTIONAL LIST [1:?] OF IfcConstraint; LogicalAggregator : OPTIONAL IfcLogicalOperatorEnum; ObjectiveQualifier : IfcObjectiveEnum; UserDefinedQualifier : OPTIONAL IfcLabel; WHERE WR21 : (ObjectiveQualifier <> IfcObjectiveEnum.USERDEFINED) OR ((ObjectiveQualifier = IfcObjectiveEnum.USERDEFINED) AND EXISTS(SELF\IfcObjective.UserDefinedQualifier)); END_ENTITY;
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标签：constraint,IfcObjective,value,IfcObjectiveEnum,ObjectiveQualifier,type From： https://www.cnblogs.com/herd/p/17562643.html