Re: Motion 52: final "Expressions" text for vote
On 2013-11-25 15:35:13 -0500, Michel Hack wrote:
> I just skimmed the article, and if I understand it correctly, the point
> it makes is that, for intervals, the restriction of the atan2() range
> to [-\pi, +\pi] would force some evaluations to return the essentially
> useless [-\pi, +\pi] instead of a sharp enclosure that straddles \pi.
>
> The same may apply to the other inverse-trig functions.
I think that atan2 is a bit particular. Do you have an example
with a conventional inverse-trig function (asin, acos, atan)?
You can have similar problems with box arithmetic on complex numbers,
like log(-1+[-eps,eps]*I), but here we have only real numbers.
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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