[R] Infinite Series

[Janh Anni]

Hello Jeff,

Thanks a lot.  I tried it and see that it prints out the entire 100 partial
sums, so I can take the last value as the partial sum for the first 100
terms. Would there be any way cumsum can print only the nth partial sum,
i.e. the last value in the array, instead of printing the entire array?
Thanks again.

Joseph

On Fri, Jul 24, 2015 at 2:02 PM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us>
wrote:

> Please reply-all so the mailing list stays in the loop.
>
> cumsum(1/(1:100)^2)
>
> gives you the partial sums up through i=100.
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> On July 24, 2015 10:30:09 AM PDT, Janh Anni <annijanh at gmail.com> wrote:
> >Hello Jeff,
> >
> >Thank you so much for the suggestion,  I searched cumsum as suggested
> >but
> >not sure it is what I had in mind.  For instance if I had the infinite
> >series:    [image: Inline image 1]
> >
> >and want to compute the sum of the, say, first 100 terms, how could I
> >use
> >cusum to do that?
> >
> >Thanks again,
> >
> >Janh
> >
> >
> >On Thu, Jul 23, 2015 at 11:51 PM, Jeff Newmiller
> ><jdnewmil at dcn.davis.ca.us>
> >wrote:
> >
> >> ?cumsum
> >>
>
> >---------------------------------------------------------------------------
> >> Jeff Newmiller                        The     .....       .....  Go
> >Live...
> >> DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
> >> Go...
> >>                                       Live:   OO#.. Dead: OO#..
> >Playing
> >> Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
> >> /Software/Embedded Controllers)               .OO#.       .OO#.
> >rocks...1k
> >>
>
> >---------------------------------------------------------------------------
> >> Sent from my phone. Please excuse my brevity.
> >>
> >> On July 23, 2015 8:23:39 PM PDT, Janh Anni <annijanh at gmail.com>
> >wrote:
> >> >Dear All,
> >> >
> >> >Does anyone know of any R functions that compute partial sums of
> >> >series?
> >> >
> >> >Thanks in advance!
> >> >
> >> >Janh
> >> >
> >> >       [[alternative HTML version deleted]]
> >> >
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> >>
>
>

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