The brute force answer involves for loops or apply functions, with or without
defining your own functions for calculating terms. More optimized methods
usually require understanding the specific structure of the summations and
unwinding them with functions like expand.grid. For more specific help, read
the Posting Guide (which among other things warns you to post in plain text)
and post a specific example of the type of problem that you want to solve.
---------------------------------------------------------------------------
Jeff Newmiller The ..... ..... Go Live...
DCN:<jdnew...@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 September 28, 2015 8:26:56 AM PDT, Maram SAlem <marammagdysa...@gmail.com>
wrote:
>Dear All,
>
>I'm trying to write and evaluate an equation which involves multiple
>summations but can't figure out how to do it.
>
>I've an numeric vector r
>r<-vector(mode = "numeric", length = m)
> and I have multiple summations (for ex.) of the form:
>
>[(sum from r[1]=0 to g(r[1])) (sum from r[2] =0 to g(r[2]))......(sum
>from
>r[m] to g(r[m]))] {the sum is over some complicated expression in
>r[1],r[2],.....,r[m]},
>
>where g(r[i]) = m- (r[1] +r[2]+...+r[i-1])
>Any suggestions for some function or a package that can help me with
>this?
>
>Many Thanks,
>Maram
>
> [[alternative HTML version deleted]]
>
>______________________________________________
>R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
