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Re: Fwd: Re: double == double

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From Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups comp.lang.java.programmer
Subject Re: Fwd: Re: double == double
Date Thu, 20 Oct 2016 07:54:13 -0400
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On 10/19/2016 9:30 PM, Arne Vajhøj wrote:
> On 10/19/2016 5:10 PM, Eric Sosman wrote:
>>     (A final point: All this argument over the sign of nothing leaves
>> me, I confess, a bit perplexed.  However, those with more numerical
>> sophistication find the distinction between +0 and -0 to be of great
>> practical importance.  William Kahan is particularly vehement on the
>> topic; look for his presentation titled "Branch Cuts for Complex
>> Elementary Functions or Much Ado About Nothing's Sign Bit," and
>> bring more mathematical prowess to your reading than I can. :)
>
> With the specification for operations then I don't think the
> existence of -0.0 has much impact on practical programming.

     Kahan ("the primary architect behind the IEEE 754-1985 standard
for floating-point computation" -- Wikipedia) disagrees.  Since he
knows a whale of a lot more about numerical computation than I ever
will, I'm inclined to take his word for it.

     (He's no fan of Java, by the way.  Look for his presentation
"How JAVA's Floating-Point Hurts Everyone Everywhere."  It starts
out rather calmly but develops into what sounds like a rant -- but
by that time its mathematics is so far above me that rantingness
may just be a figment of my lack of imagination.)

-- 
esosman@comcast-dot-net.invalid
"Don't be afraid of work. Make work afraid of you." -- TLM

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Thread

Fwd: Re: double == double Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-10-19 17:10 -0400
  Re: Fwd: Re: double == double Arne Vajhøj <arne@vajhoej.dk> - 2016-10-19 21:30 -0400
    Re: Fwd: Re: double == double Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-10-20 07:54 -0400
  Re: Fwd: Re: double == double Michael Jung <miju@golem.phantasia.org> - 2016-10-20 20:59 +0200
    Re: Fwd: Re: double == double Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-10-20 15:37 -0400
      Re: Fwd: Re: double == double Michael Jung <miju@golem.phantasia.org> - 2016-10-21 19:53 +0200

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