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Re: evaluating functions and displaying results numerically

  • To: mathgroup at
  • Subject: [mg126262] Re: evaluating functions and displaying results numerically
  • From: Murray Eisenberg <murray at>
  • Date: Fri, 27 Apr 2012 06:52:42 -0400 (EDT)
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  • References: <>
  • Reply-to: murray at

Kindkly post your code about the sum directly in an e-mail message (and 
be sure to use Copy As...Plain Text from Mathematica). Trying to deal 
with code shown just in a pdf is not easy.

On 4/26/12 5:32 AM, Alexei Boulbitch wrote:
> Thanks for the replies. I can go along with all your explanations for the Sin function, even though I havent had this interpretation of results from Mathematica before. I never had to use the N option before. What about my second enquire, reproduced below:
> In another instance, I have a summation of about 1000 terms defined as
> a function of 3 arguments. When I use numerical arguments to calculate the summation, instead of
> Mathematica calculating a numerical result it generates a symbolic
> output with all 1000 terms.
> It doesnt make sense that Mathematica chooses to do the whole thing symbolically. I have made similar calculations before, and Mathematica performed the calculation numerically. I presume that I have enabled some sort of symbolic calculation mode, but I cannot figure out where. I am attaching a a link to a pdf file showing a image of the generated result for my function called "Absorption". The other functions called by Absorption are defined prior to the definition of Absorption. I just want to show the type of result generated. Also, If I want to plot my function Absorption relative to one of the arguments, Mathematica just doesnt plot it.
> Best regards
> The output image is in the google docs file below
> It looks possible that you have some function or variable in your sum that has not been defined before and, therefore, Mathematica treats the whole thing analytically.
>> From the fragment you showed in the link it was difficult to see which one it could be. May be Ref?
> If you write your functions directly in the post, it will be easier to help you.
> Have fun, Alexei
> Alexei BOULBITCH, Dr., habil.
> IEE S.A.
> ZAE Weiergewan,
> 11, rue Edmond Reuter,
> L-5326 Contern, LUXEMBOURG
> Office phone :  +352-2454-2566
> Office fax:       +352-2454-3566
> mobile phone:  +49 151 52 40 66 44
> e-mail: alexei.boulbitch at<mailto:alexei.boulbitch at>

Murray Eisenberg                     murray at
Mathematics & Statistics Dept.
Lederle Graduate Research Tower      phone 413 549-1020 (H)
University of Massachusetts                413 545-2859 (W)
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Amherst, MA 01003-9305

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