At 08:18 PM 8/9/00 +0000, Nick Ing-Simmons wrote:
>Dan Sugalski <[EMAIL PROTECTED]> writes:
> >At 06:16 PM 8/9/00 +0000, Nick Ing-Simmons wrote:
> >>Dan Sugalski <[EMAIL PROTECTED]> writes:
> >> >>
> >> >>As an engineer I would really like to know when you are going to
> >> >>run out of precision in double - that is forty something bits of
> mantissa.
> >> >>That is more precision than you have in the real world.
> >> >
> >> >It's not precision, it's resolution. What do you do if your timers return
> >> >values in 1/10ths of a second?
> >>
> >>What is the problem with that?
> >
> >You can't accurately represent a tenth of a second with floating point
> >numbers.
>
>You could if you made 1/10th second the "unit" of the float internally.
>
> >If we're going to handle them, we might as well be exact.
>
>Why - the 1/10 of second is not exact anyway (unless you happen to
>have an atomic clock in an appropriate physical enviroment attached to
>your machine). A double's mantissa is better than your typical oscillator.
While it may not be correct, at least it's exact. If we go with an inexact
representation, we run the risk of accumulating errors and eventually
ending up with a number that's both inexact and incorrect.
Dan
--------------------------------------"it's like this"-------------------
Dan Sugalski even samurai
[EMAIL PROTECTED] have teddy bears and even
teddy bears get drunk
