IfcEllipseProfileDef

BACnet MVD

#### IfcEllipseProfileDef

Natural language names

| ellipsoides Profil - parametrische Definition
| Ellipse Profile Def
| Définition de profil ellipsoïdal

Change log

Item | SPF | XML | Change | Description
--- | --- | --- | --- | ---
IFC2x3 to IFC4
IfcEllipseProfileDef |  |  |  |
Position |  |  | MODIFIED | Instantiation changed to OPTIONAL.

##### Semantic definitions at the entity

Entity definition

IfcEllipseProfileDef defines an ellipse as the profile definition used by the swept surface geometry or the swept area solid. It is given by its semi axis attributes and placed within the 2D position coordinate system, established by the Position attribute.

> HISTORY New entity in IFC2x

Figure 364 illustrates parameters for the ellipse profile definition. The parameterized profile defines its own position coordinate system. The underlying coordinate system is defined by the swept surface or swept area solid that uses the profile definition. It is the xy plane of either:

- IfcSweptSurface.Position
- IfcSweptAreaSolid.Position

Or in case of sectioned spines it is the xy plane of each list member of IfcSectionedSpine.CrossSectionPositions. By using offsets of the position location, the parameterized profile can be positioned centric (using x,y offsets = 0.), or at any position relative to the profile. Explicit coordinate offsets are used to define cardinal points (for example, upper-left bound). The location of the position coordinate system defines the center of the ellipse. The SemiAxis1 attribute defines the first radius of the ellipse in the direction of the X axis, the SemiAxis2 attribute defines the second radius of the ellipse in the direction of the Y axis.

> NOTE The semi axes of the ellipse are rectangular to each other by definition.

Figure 364 — Ellipse profile

Attribute definitions

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
4 | SemiAxis1 | IfcPositiveLengthMeasure |  | The first radius of the ellipse. It is measured along the direction of Position.P[1]. | X | X
5 | SemiAxis2 | IfcPositiveLengthMeasure |  | The second radius of the ellipse. It is measured along the direction of Position.P[2]. | X | X

##### Inherited definitions from supertypes

Entity inheritance
Attribute inheritance

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
IfcProfileDef
1 | ProfileType | IfcProfileTypeEnum |  | Defines the type of geometry into which this profile definition shall be resolved, either a curve or a surface area. In case of curve the profile should be referenced by a swept surface, in case of area the profile should be referenced by a swept area solid. | X | X
2 | ProfileName | IfcLabel | ? | Human-readable name of the profile, for example according to a standard profile table. As noted above, machine-readable standardized profile designations should be provided in IfcExternalReference.ItemReference. | X | X

HasExternalReference

IfcExternalReferenceRelationship
@RelatedResourceObjects

S[0:?]

Reference to external information, e.g. library, classification, or document information, which is associated with the profile.

> IFC4 CHANGE New inverse attribute

X

HasProperties

IfcProfileProperties
@ProfileDefinition

S[0:?]

Additional properties of the profile, for example mechanical properties.

> IFC4 CHANGE New inverse attribute

X

IfcParameterizedProfileDef
3 | Position | IfcAxis2Placement2D | ? | Position coordinate system of the parameterized profile definition. If unspecified, no translation and no rotation is applied. | X | X
IfcEllipseProfileDef
4 | SemiAxis1 | IfcPositiveLengthMeasure |  | The first radius of the ellipse. It is measured along the direction of Position.P[1]. | X | X
5 | SemiAxis2 | IfcPositiveLengthMeasure |  | The second radius of the ellipse. It is measured along the direction of Position.P[2]. | X | X

##### Formal representations

XML Specification
`<xs:element name="IfcEllipseProfileDef" type="ifc:IfcEllipseProfileDef" substitutionGroup="ifc:IfcParameterizedProfileDef" nillable="true"/>
<xs:complexType name="IfcEllipseProfileDef">
<xs:complexContent>
<xs:extension base="ifc:IfcParameterizedProfileDef">
<xs:attribute name="SemiAxis1" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
<xs:attribute name="SemiAxis2" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
`
EXPRESS Specification
`ENTITY IfcEllipseProfileDef
SUBTYPE OF (IfcParameterizedProfileDef);
SemiAxis1 : IfcPositiveLengthMeasure;
SemiAxis2 : IfcPositiveLengthMeasure;
END_ENTITY;

EXPRESS-G diagram

`

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