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Date: Wed, 25 Jul 2012 10:31:47 -0700
From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: Stephen Montgomery-Smith <stephen@missouri.edu>
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Cc: David Schultz <das@freebsd.org>, Bruce Evans <bde@freebsd.org>,
	freebsd-current@freebsd.org
Subject: Re: Use of C99 extra long double math functions after r236148
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On Wed, Jul 25, 2012 at 12:27:43PM -0500, Stephen Montgomery-Smith wrote:
> On 07/25/12 11:29, Rainer Hurling wrote:
> 
> >Many thanks to you three for implementing expl() with r238722 and r238724.
> >
> >I am not a C programmer, but would like to ask if the following example
> >is correct and suituable as a minimalistic test of this new C99 function?
> >
> >

(program deleted)

> >
> >Compiled with 'c99 -o math_expl math_expl.c -lm' and running afterwards
> >it gives me:
> >
> >exp(2.000000)  is
> >7.3890560989306504069
> >
> >expl(2.000000) is
> >7.38905609893065022739794
> >
> 
> Just as a point of comparison, here is the answer computed using 
> Mathematica:
> 
> N[Exp[2], 50]
> 7.3890560989306502272304274605750078131803155705518
> 
> As you can see, the expl solution has only a few digits more accuracy 
> that exp.

Unless you are using sparc64 hardware.

flame:kargl[204] ./testl -V 2
ULP = 0.2670 for x = 2.000000000000000000000000000000000e+00
mpfr exp: 7.389056098930650227230427460575008e+00
libm exp: 7.389056098930650227230427460575008e+00


-- 
Steve