From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] comparisons with NaN
Date: Wed, 21 Aug 2013 12:55:31 -0400 [thread overview]
Message-ID: <c93098b57ad99db811eb93d220b25f46@kw.quanstro.net> (raw)
In-Reply-To: <04891ed00c35de2583c1da9a017dd7e2@hamnavoe.com>
On Wed Aug 21 12:09:26 EDT 2013, 9fans@hamnavoe.com wrote:
> > at least in terms of passing floating point test suites
> > (like python's) the NaN issue doesn't come up
>
> Actually it was a test suite that revealed the NaN errors.
> I wouldn't think it's something anyone needs in normal
> day-to-day computation, but sometimes boxes must be ticked.
:-) it is hard to imagine how this is useful. it's not like
∑{i→∞}-0 is interesting. at least ∏{i→∞}-0 has an alternating
sign. (so does it converge with no limit?)
the difference i have seen is a situation like
atan2(-0, x) ≡ -π
atan2(+0, x) ≡ pi, ∀ x<0.
any ideas on how this is useful?
- erik
next prev parent reply other threads:[~2013-08-21 16:55 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-21 13:17 Richard Miller
2013-08-21 14:34 ` erik quanstrom
2013-08-21 16:08 ` Richard Miller
2013-08-21 16:55 ` erik quanstrom [this message]
2013-08-21 17:42 ` Bakul Shah
2013-08-21 17:47 ` erik quanstrom
2013-08-21 18:00 ` Bakul Shah
2013-08-21 18:00 ` Richard Miller
2013-08-21 18:24 ` Charles Forsyth
2013-08-22 14:05 ` Richard Miller
2013-08-22 14:25 ` Charles Forsyth
2013-09-20 9:05 ` Richard Miller
2013-08-21 14:36 ` erik quanstrom
2013-08-21 18:24 ` lucio
2013-08-21 18:27 ` erik quanstrom
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