Is this what you want? You will have to adjust the indices appropriately: > x<-c(2,0,0,2,2,2) > i <- seq_along(x) > x[i] [1] 2 0 0 2 2 2 > # to "loop around", change how you index > x[(i - 1) %% length(x) + 1] [1] 2 0 0 2 2 2 > i <- i + 1 > x[(i - 1) %% length(x) + 1] [1] 0 0 2 2 2 2 > i <- i + 1 > x[(i - 1) %% length(x) + 1] [1] 0 2 2 2 2 0 > i <- i + 1 > x[(i - 1) %% length(x) + 1] [1] 2 2 2 2 0 0 > > >
On Wed, Dec 21, 2011 at 6:56 AM, djrwicks <djrwi...@gmail.com> wrote: > Given the following, how to I get x[i+1] to not return an NA result when it > gets to the end of list x by looping back to the start of the list > i.e should return: 0 0 2 2 2 2? > >> x<-c(2,0,0,2,2,2) >> i<-1:length(x) >> x[i] > [1] 2 0 0 2 2 2 >> x[i+1] > [1] 0 0 2 2 2 NA > > can i be described using a loop that says go back to the beginning of list > x? > > -- > View this message in context: > http://r.789695.n4.nabble.com/creating-a-closed-loop-for-a-list-tp4221333p4221333.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > 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. -- Jim Holtman Data Munger Guru What is the problem that you are trying to solve? Tell me what you want to do, not how you want to do it. ______________________________________________ R-help@r-project.org mailing list 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.
