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Date: Thu, 28 Aug 2014 22:50:55 +1000
From: RobG <rgqld@iinet.net.au>
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To: "Christoph M. Becker" <cmbecker69@arcor.de>
Subject: Re: IE and IEEE 754
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On 28/08/2014 6:08, Christoph M. Becker wrote:
> RobG wrote:
>
>> In most browsers:
>>
>>    0.57 + 8.36 + 3.36 + 0.19 = 12.479999999999999
>>
>> in IE it returns:
>>
>>    12.479999999999998
>>
>> Is IE wrong, or is the above difference allowable within IEEE 754?
>
> Both string representations will be parsed as the same double-precision
> 64-bit binary format IEEE 754 value[1]:
>
>    100000000101000111101011100001010001111010111000010100011110101
>
> (Therefore: 12.479999999999999 === 12.479999999999998)
>
> The different string representation is allowed for conforming ECMAScript
> implementations according to ECMA-262 5.1 Edition, section 9.8.1 step 5[2].
>
> [1] <http://www.merlyn.demon.co.uk/js-exact.htm#DW4>
> [2] <http://ecma-international.org/ecma-262/5.1/#sec-9.8.1>

Thanks, that seems definitive.

-- 
Rob





-- 
Rob