StrictEquiv

An equivalence for Doubles which is reflexive (treats all NaNs as equivalent), and treats -0.0 and 0.0 as not equivalent; it behaves the same as java.lang.Double.compare.

Because the behaviour of Doubles specified by IEEE is not consistent with behaviors required of an equivalence relation for NaN (it is not reflexive), there are two equivalences defined for Double: StrictEquiv, which is reflexive, and IeeeEquiv, which is consistent with IEEE spec and floating point operations defined in scala.math.

This equivalence may be preferable for collections.