[Haskell] Literal for Infinity
Frederik Eaton
frederik at a5.repetae.net
Mon Oct 3 08:38:37 EDT 2005
But they all have a largest and smallest possible value, as I have
already indicated.
On Sun, Oct 02, 2005 at 04:35:02PM +0200, Lennart Augustsson wrote:
> Not all FP representations have infinity, and even if
> they do, they might only have one infinity.
>
> -- Lennart
>
> Frederik Eaton wrote:
> >I've previously mentioned that I would like to see an 'instance
> >Bounded Double' etc., as part of the standard, which would use 1/0 for
> >maxBound, or the largest possible value (there must be one!) for
> >platforms where that is not possible. I don't see a problem with
> >looking at Double values as if they were bounded by -infinity and
> >+infinity.
> >
> >On Thu, Sep 29, 2005 at 09:11:25PM +0300, Yitzchak Gale wrote:
> >
> >>Hi Jacques,
> >>
> >>Thanks also to you for a most interesting reply.
> >>
> >>This same discussion has taken place on the
> >>discussion list of every modern general-purpose
> >>programming language.
> >>
> >>The same points are always raised and argued, and
> >>the conclusion is always the same: floating point
> >>exceptions should raise exceptions. Programs that
> >>are so sensitive that the tiny overhead makes a
> >>difference should use numeric libraries, unboxed
> >>types, FFI, and the like.
> >>
> >>In Haskell also, it looks like the infrastructure
> >>was already laid in the Control.Exception module.
> >>I hope we will soon be using it.
> >>
> >>I personally would like also to see alternative
> >>functions that return values in the Error monad.
> >>
> >>Regards,
> >>Yitz
> >>
> >>On Thu, Sep 29, 2005 at 03:13:27PM +0300, Jacques Carette wrote:
> >>
> >>>The IEEE 754 standard says (fairly clearly) that +1.0 / +0.0 is one of
> >>>the most 'stable' definitions of Infinity (in Float at least).
> >>>Throwing an exception is also regarded as a possibility in IEEE 754, but
> >>>it is expected that that is not the default, as experience shows that
> >>>that is a sub-optimal default. Mathematical software (Maple,
> >>>Mathematica, Matlab) have generally moved in that direction.
> >>>
> >>>Almost all hardware implementations of float arithmetic now default to
> >>>IEEE 754 arithmetic. Having the arithmetic do 'something else' involves
> >>>more CPU cycles, so users should generally complain if their system's
> >>>arithmetic differs from IEEE 754 arithmetic without some deep reason to
> >>>do so [there are some; read and understand William Kahan's papers for
> >>>these].
> >>>
> >>>Jacques
> >>
> >>_______________________________________________
> >>Haskell mailing list
> >>Haskell at haskell.org
> >>http://www.haskell.org/mailman/listinfo/haskell
> >>
> >
> >_______________________________________________
> >Haskell mailing list
> >Haskell at haskell.org
> >http://www.haskell.org/mailman/listinfo/haskell
> >
>
More information about the Haskell
mailing list