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From: "Christoph M. Becker" <cmbecker69@arcor.de>
Newsgroups: comp.lang.javascript
Subject: Re: IE and IEE 754
Date: Thu, 28 Aug 2014 02:55:40 +0200
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Ben Bacarisse wrote:

> "Christoph M. Becker" <cmbecker69@arcor.de> writes:
> 
>> Evertjan. wrote:
> <snip>
>>> If you are a sticker for correctness and these are monitary values,
>>> like $ or [euro-sign], use integer cent values in variables, and
>>> write decimals with string manupulation.
>>
>> Are you suggesting that storing $123.45 as 12345 is better than storing
>> it as 123.45?  As ECMAScript implementations typically have no integer
>> type, there is no difference regarding the precision of further
>> calculations.
> 
> 12345 can be represented exactly in binary floating point (given enough
> bits, and we certainly have that) whereas 123.45 can't be.
<snip>

Thanks for pointing this out. :) After quite some reconsideration I have
to admit that I was wrong.  Of course, 123.45 can't be represented
exactly as *binary* floating point number, while 12345 can be.

However, it seems to me that multiplying 123.45 (0x405edccccccccccd)
with 100 doesn't solve the issue, i.e. the result is not necessarily
equal to 12345 (0x40c81c8000000000).

-- 
Christoph M. Becker