Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: "Disjoint" relation



Ulrich Kulisch wrote:
Motion 13.04 states that {\ol{IR}, subset of} is a lattice and that its infimum is the intersection. Why not just check whether the intersection (simple formula) is empty?

One can do that, of course.

With a similar argument, one does not need to provide any comparison,
E.g., one can test for precedes(A,B) by checking whether sup(A)<=inf(B).


On the other hand, unlike for ''precedes'', computing the intersection
and then testing for emptiness is more expensive than checking
disjointness directly.



Arnold Neumaier