Re: Putting features in vs. leaving them out, especially functions
On Wed, May 25, 2011 10:06, John Pryce wrote:
> - I rather disagree with George on reverse operations. Constraint
> Programming seems
> an important application (I know little about it) and it needs
> operations of
> the form "enclose the set of all x in xx for which f(x) is in yy"
> where f is some
> elementary operation. In CP applications I guess these are
> performance-critical;
> if so, that seems a reason to have them in the standard.
> Stuff like (1-cos x)/x^2: people to whom these are
> important are
> competent enough to code them themselves; they are unlikely to be
> performance-
> critical.
They are needed for the efficient implementations of slopes and
second-order slopes, which we use in our COCONUT global optization
environment almost as much as CP.