From: Jamis Buck <jgb3@...>
Date: 2004-10-28T05:57:53+09:00
Subject: Re: Rounding error, (100.0 * 9.95).to_i == 994

trans. (T. Onoma) wrote:
> On Wednesday 27 October 2004 04:36 pm, Hal Fulton wrote:
> | Jason DiCioccio wrote:
> | > I'm confused now..  100.0 * 9.95 is clearly 995.  So what exactly is the
> | > issue with floating point numbers is making this come out to
> | > 994.999999999983 (or wahtever ;))?  If every language is plagued by this
> | > problem, then I'd be curious to know the history behind it..
> | >
> | :) It's not history, it's math.
> |
> | Here's the short explanation.
> |
> | Remember repeating decimals, which you learned about in elementary school?
> | For example, 1/3 = 0.33333... can't be expressed in a finite number of
> | digits.
> 
> Not exactly, '1/3' is finite.

... That's not what I learned in school. How many decimal digits does it 
take to express 1/3, then?

- Jamis

-- 
Jamis Buck
jgb3@email.byu.edu
http://www.jamisbuck.org/jamis