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Student Support Forum: 'Slowdown of computation of multiple sums' topicStudent Support Forum > General > "Slowdown of computation of multiple sums"

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Vojta
12/08/12 08:37am

In Response To 'Re: Slowdown of computation of multiple sums'
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Let me rephrase my question. Lets say I want to make sum
Sum[function[n],{n,min,max}]

where function[n] is defined as
function[n_]:=Sum[differentfunction[n,i,j,k],{i,imin,imax},{j,jmin,jmax},{k,kmin,kmax}]

where differentfunction[n,i,j,k] can be quite complicated function which could even contain i-th derivatives of some genereting function etc.

Now, when the sum over n is calculated, will it have to run internally in every term for every n all the summations over i,j,k which are in the definition of function[n]? Or will those sums be done at the beginning and then Mathematica will just insert values of n from nmin to nmax?

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Subject (listing for 'Slowdown of computation of multiple sums')
Author Date Posted
Slowdown of computation of multiple sums Vojta 11/26/12 4:04pm
Re: Slowdown of computation of multiple sums Bill Simpson 11/29/12 3:51pm
Re: Re: Slowdown of computation of multiple sums Vojta 12/08/12 08:37am
Re: Slowdown of computation of multiple sums Bill Simpson 12/08/12 8:01pm
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