Re: Re: Re: Bug in 5.1??

*To*: mathgroup at smc.vnet.net*Subject*: [mg54534] Re: [mg54489] Re: [mg54448] Re: [mg54349] Bug in 5.1??*From*: János <janos.lobb at yale.edu>*Date*: Tue, 22 Feb 2005 04:24:10 -0500 (EST)*References*: <200502210845.DAA27260@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Taking into account those $billions missing from the US budget from year to year, minimum the US government must be using 2 digit precision or less :) Smile, János On Feb 21, 2005, at 3:45 AM, Andrzej Kozlowski wrote: > I never wrote this makes sense. I only pointed out that if you think it > is a bug you should report it. On the other hand it has been a part of > Mathematica since the first version I used, which was version 1.2, I > think. Since then this issue has been discussed almost every year. From > what has been explained, both on this list and in other places, it is a > consequence of certain shortcuts that Significance arithmetic makes to > achieve reasonable speed. It is harmless because nobody ever needs to > compute anything with two digits of precision. > Andrzej Kozlowski > On 20 Feb 2005, at 17:58, DrBob wrote: >> N[50000,2] should represent something between, say, 49500 and 50500, >> both of which are positive. If it means something other than that, >> please enlighten us!! >> Meanwhile, perhaps we can use Interval to interpret it: >> Interval[N[50000, 2]]//InputForm >> Interval[ >> {49488.`1.9955298983230858, >> 50512.`2.0044245602121236}] >> Interval@N[50000,2]>0 >> True >> So I don't see how this makes sense: >> N[50000,2]>0 >> False >> Bobby >> On Sun, 20 Feb 2005 10:53:16 +0100, Andrzej Kozlowski >> <akoz at mimuw.edu.pl> wrote: >>> *This message was transferred with a trial version of CommuniGate(tm) >>> Pro* >>> Then surely you must have filed a bug report as it would be >>> irresponsible not to! >>> Andrzej Kozlowski >>> On 20 Feb 2005, at 06:10, DrBob wrote: >>>> This behavior will find defenders, I'm sure, but it certainly looks >>>> like a bug to ME. >>>> Bobby >>>> On Sat, 19 Feb 2005 02:31:49 -0500 (EST), Gehrmann, James E >>>> <jgehrman at saclink.csus.edu> wrote: >>>>> I'm running Mathematica v. 5.1 under WinXP and had the following >>>>> interaction with Mathematica: >>>>> 5>0 >>>>> True >>>>> 5.>0 >>>>> True >>>>> N[5]>0 >>>>> True >>>>> N[5,3]>0 >>>>> True >>>>> N[5,2]>0 >>>>> False >>>>> N[50000,2]>0 >>>>> False >>>>> Are the last two results a bug or am I not understanding the N >>>>> function? >>>>> Thanks for you help. >>>> -- >>>> DrBob at bigfoot.com >>>> www.eclecticdreams.net >> -- >> DrBob at bigfoot.com >> www.eclecticdreams.net ------------------------------------------------ ``Our enemies are innovative and resourceful, and so are we. They never stop thinking about new ways to harm our country and our people, and neither do we.'' -- George W. Bush

**References**:**Re: Re: Bug in 5.1??***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>