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Re: Many new math failures


On Thu, 2002-06-27 at 05:29, Stephen L Moshier wrote:
> 
> > Test "Real part of: cacosh (0.75 + 1.25 i) ==
> >1.13239363160530819522266333696834467 +
> >1.11752014915610270578240049553777969 i":
> >@@ -310,8 +308,8 @@
> > float: 3
> > idouble: 1
> > ifloat: 3
> >-ildouble: 37
> -ldouble: 37
> >+ildouble: 370
> >+ldouble: 370
> 
> This is due to arithmetic cancellation error inside the function routine.
> It might be better to use the identity cacosh(x) = I * cacos(x) here.

No, the excerpt from the patch is misleading.  See the @@ line?  The 370
ulps error is for cpow.

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