The UnitVector2dSimpleType is an array of two double values. used to represent a 2D unit vector. The first entry in the list is the X component (I) and the second entry is the Y component (J). A UnitVector2dSimpleType should be of unit length to the limits of accuracy of the executing system, and in any event must not be less than 0.99999999 or greater than 1.00000001.
<xs:simpleType name="UnitVector2dSimpleType"><xs:annotation><xs:documentation>The UnitVector2dSimpleType is an array of two double values. used to represent a 2D unit vector. The first entry in the list is the X component (I) and the second entry is the Y component (J). A UnitVector2dSimpleType should be of unit length to the limits of accuracy of the executing system, and in any event must not be less than 0.99999999 or greater than 1.00000001.</xs:documentation></xs:annotation><xs:restriction base="ListDoubleType"><xs:length value="2"/></xs:restriction></xs:simpleType>