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Re: Work on Basic Mathematica Stephen!

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  • Subject: [mg130809] Re: Work on Basic Mathematica Stephen!
  • From: Peter Klamser <klamser at googlemail.com>
  • Date: Fri, 17 May 2013 04:35:46 -0400 (EDT)
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... thank you for the response.

Every WRI employee writes this since years, but "fuzz" stays "fuzz"
and "fuzz" is not essential.

Peter

2013/5/16 Murray Eisenberg <murray at math.umass.edu>:
> If I understand this proposal aa), then I completely disagree. It is *essential* to have the ability to use a function Chop that, e.g., does the following:
>
>    Chop[4. + 10.^-16 I]
> 4.
>
> The reason is that even when one starts with strictly real functions, it is often the case that Mathematica uses complex-function methods and, due to roundoff, returns results with some pure imaginary "fuzz".
>
> On May 16, 2013, at 3:28 AM, Peter Klamser <klamser at googlemail.com> wrote:
>
>> . .. A) First proposal: Identify useless or false constructions in Mathematica
>>
>> aa) Eliminating Chop[] for complex numbers. Complex numbers are
>> oderless and therefore nobody call estimate, weather the distance of 1
>> + 10^-google i to the real numbers is small or big. Chop[] is the
>> result of Mathematica design, that it presents often complex results, where
>> real values are the simpler result and can be reached by
>> ComplexExpand[].
>> The simplest solution is always the best solution.
>
> ---
> Murray Eisenberg                                    murray at math.umass.edu
> Mathematics & Statistics Dept.
> Lederle Graduate Research Tower            phone 413 549-1020 (H)
> University of Massachusetts                               413 545-2838 (W)
> 710 North Pleasant Street                         fax   413 545-1801
> Amherst, MA 01003-9305
>
>
>
>
>



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