Re: Interval comparisons
John Pryce wrote:
> (all x in xx) (exist y in yy) E(x) = y,
> which is the definition of: yy is an enclosure of range(f,xx).
I fully agree. This is my preferred definition of range(f,xx). I wish it
could be included in our motions and standard.
Furthermore, if and only if
(all x in xx)(exist y in yy) E(x) = y
(all y in yy)(exist x in xx) E(x) = y
are both true, then range(f,xx) is an exact enclosure (as opposed to some
outward rounding).
The latter can also define the inner rounding/enclosure, as well.
Nate Hayes