Groups > comp.lang.javascript > #31948

Re: Why JavaScript has two zeros

Path	csiph.com!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From	Dr J R Stockton <reply1600@merlyn.demon.co.uk.invalid>
Newsgroups	comp.lang.javascript
Subject	Re: Why JavaScript has two zeros
Date	Thu, 22 Dec 2016 23:43:21 +0000
Organization	Home
Lines	29
Message-ID	<LMKbWltZUGXYFwDf@invalid.uk.co.demon.merlyn.invalid> (permalink)
References	<84234e86-ac01-4a9e-9d21-dc1cdc30678c@googlegroups.com> <1bm6A.536745$IJ6.194196@fx46.am4>
Mime-Version	1.0
Content-Type	text/plain;charset=iso-8859-1
Content-Transfer-Encoding	8bit
Injection-Info	mx02.eternal-september.org; posting-host="2c9044a8c1bf9316db8b97a6f33340d2"; logging-data="31096"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1933vMT+qIipoaIbqp9Pd0NGk9imBBOnDY="
User-Agent	Turnpike/6.05-S (<hY+ExRCkcsssDA9uJ+0bCn8+UA>)
Cancel-Lock	sha1:Wk4rfGp48BSk/yAbgKfpkvTybaI=
Xref	csiph.com comp.lang.javascript:31948

Show key headers only | View raw

In comp.lang.javascript message <1bm6A.536745$IJ6.194196@fx46.am4>, Wed,
21 Dec 2016 02:55:57, cyber@2trom.com posted:

>abdulapopoola@gmail.com wrote:
>> Do you know that there are actually two zero value types in
>>JavaScript (as well as most languages)? Read to know why this matters,
>>what scenarios to watch out for and some of the quirks of the IEEE 754
>>standard.
>>
>> https://abdulapopoola.com/2016/12/19/why-javascript-has-two-zeros-0-and-0/
>
>I imagine that also having -0i and 0i might be too complex for JavaScript.

JavaScript has two zeroes (of equal but distinguishable values) because
IEEE 754 is a sign-magnitude-exponent representation.  They are the
reciprocals of the two infinities.  long-established readers with good
memories should recall at least one occasion on which having two zeroes
was arithmetically useful.

In JavaScript one can set PlusI = [0,+1] and MinusI = [0,-1], and write
arithmetic functions to operate on and return values of that nature.  It
is known that Math.POW(PlusI, PlusI) should return
0.207879576350761908546955... - and other values.

-- 
 (c) John Stockton, Surrey, UK.  ¬@merlyn.demon.co.uk   Turnpike v6.05   MIME.
 Merlyn Web Site <                       > - FAQish topics, acronyms, & links.

Thread

Why JavaScript has two zeros abdulapopoola@gmail.com - 2016-12-19 21:09 -0800
  Re: Why JavaScript has two zeros "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2016-12-20 11:46 +0100
    Re: Why JavaScript has two zeros John Harris <niam@jghnorth.org.uk.invalid> - 2016-12-20 17:58 +0000
      Re: Why JavaScript has two zeros "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2016-12-20 23:56 +0100
        Re: Why JavaScript has two zeros John Harris <niam@jghnorth.org.uk.invalid> - 2016-12-21 13:59 +0000
  Re: Why JavaScript has two zeros <cyber@2trom.com> - 2016-12-21 02:55 +0000
    Re: Why JavaScript has two zeros Dr J R Stockton <reply1600@merlyn.demon.co.uk.invalid> - 2016-12-22 23:43 +0000
      Re: Why JavaScript has two zeros "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2016-12-23 09:04 +0100
        Re: Why JavaScript has two zeros Dr J R Stockton <reply1600@merlyn.demon.co.uk.invalid> - 2016-12-25 22:15 +0000
        Re: Why JavaScript has two zeros Dr J R Stockton <reply1600@merlyn.demon.co.uk.invalid> - 2016-12-25 23:39 +0000
      Re: Why JavaScript has two zeros Tim Streater <timstreater@greenbee.net> - 2016-12-23 09:05 +0000
      Re: Why JavaScript has two zeros Ram Tobolski <ramtob@gmail.com> - 2016-12-24 02:28 -0800
        Re: Why JavaScript has two zeros Dr J R Stockton <reply1600@merlyn.demon.co.uk.invalid> - 2016-12-25 22:00 +0000
    Re: Why JavaScript has two zeros "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2016-12-26 12:08 -0800
  Why JavaScript has two zeros Ram Tobolski <ramtob@gmail.com> - 2016-12-21 10:20 -0800
  Re: Why JavaScript has two zeros "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2016-12-26 12:03 -0800

csiph-web