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From: Stephen Montgomery-Smith <stephen@missouri.edu>
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	Stephen Montgomery-Smith <stephen@FreeBSD.org>
Subject: Re: bin/170206: complex arcsinh, log, etc.
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Yes, everywhere I said "double precision" I meant "doubled precision."

I think the papers by Hull et al were perfectly happy with a ULP of 
around 4.

I have been trying to do a little better, but like you I am noticing 
that log1p isn't that good either.

I have tried some other things.  I am attaching this example which gets 
a ULP a little over 2.  I simulate high precision arithmetic by 
expanding everything out into integers.  I certainly didn't aim for a 
speedy program.

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