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Date: Sat, 31 Dec 2005 05:26:12 +1100
From: Peter Jeremy <PeterJeremy@optushome.com.au>
To: Steve Kargl <sgk@troutmask.apl.washington.edu>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Implementations of sqrtl and logl
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On Thu, 2005-Dec-29 14:46:26 -0800, Steve Kargl wrote:
>I have implementations for sqrtl and logl, which can be added
>to libm.  In limited testing on AMD64 , I find
>
>troutmask:kargl[208] ./test_sqrt 
>     float         double        long double
>MRE: 8.953800e-08  1.664855e-16  1.084202e-19
>DDP: 7.05          15.78         18.96
>BDP: 23.41         52.42         63.00
...
>MRE = maximum relative error between a value from my routine and
>      a value computed using GMP/MPFR with 64-bits of precision.

Given that long double has 64 bits of precision, is testing it against
a 64-bit test library adequate?  And what is the accuracy of your test
library?

-- 
Peter Jeremy