From: Rich Felker <dalias@libc.org>
To: musl@lists.openwall.com
Subject: Re: [musl] casinh function accuracy problem
Date: Tue, 11 Feb 2020 21:00:23 -0500 [thread overview]
Message-ID: <20200212020023.GV1663@brightrain.aerifal.cx> (raw)
In-Reply-To: <alpine.LRH.2.02.2002121031560.9274@key0.esi.com.au>
On Wed, Feb 12, 2020 at 11:46:08AM +1100, Damian McGuckin wrote:
> On Tue, 11 Feb 2020, Rich Felker wrote:
>
> >High-quality complex math functions are a long-term wishlist item for
> >musl but nobody has stepped up to do them and I don't really feel like
> >doing it, at least not over other improvements I could be working on.
>
> As you say, they do work reasonably well even now.
>
> With even complex arithmetic being "unspecified" in IEEE-754-2019,
> it is an interesting issue where "interesting" does not have the
> conventional English sense of being a positive thing.
>
> >This might be an area well-served by sponsored enhancement if there's
> >a user who needs them improved with resources to pay someone to do it.
>
> Depending on your definition of "improved", it is anything from a
> big task to a huge task.
>
> And sadly, I have other things on my plate too.
My minimal criterion for large-scale improvements of src/complex would
be fixing any remaining cases where inf/nan behavior is badly wrong or
there's catastrophic error (>2^52 ulp, or even just >2^20 ulp or so).
Beyond that, I think "reducing ulp error" would be nice but hard to
quantify and make a goal without having an idea how bad it is now, not
to mention without having rigorous error bounds on the real math
library functions.
Rich
next prev parent reply other threads:[~2020-02-12 2:00 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-11 15:51 mg1633068
2020-02-11 19:30 ` Szabolcs Nagy
2020-02-11 23:24 ` Rich Felker
2020-02-12 0:46 ` Damian McGuckin
2020-02-12 2:00 ` Rich Felker [this message]
2020-02-12 4:07 ` Damian McGuckin
2020-02-12 4:19 ` Rich Felker
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