The global Segment13Core element is the mathematical core of a 3D linear segment. It represents a portion of a 3D line defined and bounded by a start point and an end point.
The required domain attribute is the domain of the parameterization of the curve.
Source
<xs:element name="Segment13Core" type="Segment13CoreType" substitutionGroup="Curve13Core"><xs:annotation><xs:documentation>The global Segment13Core element is the mathematical core of a 3D linear segment. It represents a portion of a 3D line defined and bounded by a start point and an end point.</xs:documentation></xs:annotation></xs:element>