MathGroup Archive 2005

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Re: odd mathematica blindspot

  • To: mathgroup at
  • Subject: [mg56548] Re: [mg56502] Re: odd mathematica blindspot
  • From: Edward Peschko <esp5 at>
  • Date: Thu, 28 Apr 2005 02:40:51 -0400 (EDT)
  • References: <d4klbs$eg7$> <>
  • Sender: owner-wri-mathgroup at

From: Edward Peschko <esp5 at>
To: mathgroup at
Subject: [mg56548] Re: [mg56502] Re: odd mathematica blindspot

On Tue, Apr 26, 2005 at 09:53:49PM -0400, Skirmantas wrote:
> Hi Ed,
> By definition, 9999999999999/10000000000000 is an exact rational number, whereas 0.5 is an approximate real number:

Well, that's completely unintuitive..  I understand it, but it still rubs me the 
wrong way for some reason. '.5' on paper means that to me - .5 - not .4999999999
or .50000000001 or whatever internal representation the computer chooses.. In fact, 
that's why I got Mathematica in the first place, to get away from this approximate

Why couldn't mathematica treat .5 as a string, make the internal calculation 
and turn .5 into 5/10? Or, barring that, is there a conversion function for this 
(going back and forth between rational and approximate real?


  • Prev by Date: Re: Floor[] Not An Integer?
  • Next by Date: can Mathematica be useful for this?
  • Previous by thread: Re: odd mathematica blindspot
  • Next by thread: Re: Re: Re: odd mathematica blindspot