Stable Numerics Subroutine Library
Programming Reference Manual
Version 1.1 DD-00006-011

5.5.4 Certain comparison

bool ceq(const interval<T>&, const interval<T>&); 
bool cne(const interval<T>&, const interval<T>&); 
bool cle(const interval<T>&, const interval<T>&); 
bool cge(const interval<T>&, const interval<T>&); 
bool clt(const interval<T>&, const interval<T>&); 
bool cgt(const interval<T>&, const interval<T>&);

Certain comparison operators check that the intervals do not overlap for their respective comparison operation. As follows for a logical comparison operator □ ∈{=,̸=,<,≤,>,≥} for X,Y ∈ IR  certain comparison operators are defined as:

X□Y ≡ (X,Y  ̸=∅)∧ (∀a∈X, ∀b∈ Y :a□b)