Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2013

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

Search the Archive

Re: Why FullForm[916.536 + 3.3] gives 919.8359999999999?`

  • To: mathgroup at smc.vnet.net
  • Subject: [mg132107] Re: Why FullForm[916.536 + 3.3] gives 919.8359999999999?`
  • From: "Nasser M. Abbasi" <nma at 12000.org>
  • Date: Fri, 6 Dec 2013 02:17:06 -0500 (EST)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com
  • Delivered-to: l-mathgroup@wolfram.com
  • Delivered-to: mathgroup-outx@smc.vnet.net
  • Delivered-to: mathgroup-newsendx@smc.vnet.net
  • References: <l7pbp3$gbk$1@smc.vnet.net>
  • Reply-to: nma at 12000.org

On 12/5/2013 1:59 AM, Guillermo Sanchez wrote:
> FullForm[916.536 + 3.3] gives 919.8359999999999 instead of 919.836?
>
> Guillermo
>

computers use computation using floating points. And the above is
the result of adding large floating point to small floating point.  

Same result in Mat*ab

---------------------
EDU>> format long
EDU>> 916.536 + 3.3

      9.198359999999999e+02
--------------------

What you see on the screen with:

---------------------
916.536 + 3.3
     919.836  <------------- OUT
---------------------

Then the 919.836 is not the actual value inside the computer. If
you point the mouse to the end of the outout cell above and hit
enter, you'll get the actual value

     919.8359999999999`

which is the FullForm

--Nasser





  • Prev by Date: Re: gives 919.8359999999999?`
  • Next by Date: Re: Laptop numpad enter does not evaluate cell
  • Previous by thread: Re: gives 919.8359999999999?`
  • Next by thread: Re: gives 919.8359999999999?`