Used to determine when two points are close enough to be considered to be equivalent in certain spatial tests. In FDO, the tolerance value is used as a radius around a position rather than as a distance along an axis. In the majority of cases, the distance between the points is compared to the tolerance using the 'less than or equals to' predicate rather than the 'less than' predicate. If the X and Y tolerances are both 0.05, then point B (1.0, 1.0) is considered to be equivalent to point A (0.96, 0.96) and point C (1.04, 1.04), but is not considered to be equivalent to point D (0.96, 0.94) or point E (1.04, 1.06). The relationship is not commutative. That is, point A is not equivalent to point C. Repeated applications of the isEquivalentTo predicate to the same data always yields the same result.