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Re: "still unclear on infinite intervals"

On May 25 2011, Ralph Baker Kearfott wrote:


Wasn't the "still unclear" addressed when motion 3 passed?
That motion states that intervals are closed and connected
sets of real numbers.  Thus, 0 * (any interval) = 0
(and infinite bounds are not to be construed to mean
infinity is included.)

P.S. Other extended interval arithmetics define 0*\infty, and
     can also be used.  However, we have decided to standardize
     with 0*interval = 0.  (personal opinion): it is more important,
     at least in this case, that the programmer know how the system
     defines it, and that the system is the same across platforms,
     than what the actual definition is.


The REALLY critical thing is that it is consistent.  If you adopt
that approach, then anything/0 (or an interval containing it) MUST
be a NaN (and not (-inf,+inf)), and there must be no way to lose NaNs.

Regards,
Nick Maclaren.