> n<-7 > rep(seq(1,n,2), each=4)+c(0,1,0,1) [1] 1 2 1 2 3 4 3 4 5 6 5 6 7 8 7 8
rep(), seq(), rbind(), apply() ... whatever: internally there will always be iteration via some loop :-) Ia. On Mon, Nov 11, 2013 at 11:16 AM, Carl Witthoft <c...@witthoft.com> wrote: > Here's a rather extreme solution: > > foo<-rep(1:6,each=2) > Rgames> foo > [1] 1 1 2 2 3 3 4 4 5 5 6 6 > > Rgames> foo[rep(c(1,3,2,4),3)+rep(c(0,4,8),each=4)] > [1] 1 2 1 2 3 4 3 4 5 6 5 6 > > In the general case, then, it would be something like > > foo<- rep(1:N, each = 2) # foo is of length(2*N) > > foo[rep(c(1,3,2,4),2*N/4 + rep( seq(0, 3*N/4,by=4),each=4)] > > Note that the refolding requires the sequence to have length a multiple of > 4. > > > > > Patrick Burns wrote > >> f1 > > function(x) { > > one <- matrix(1:x, nrow=2) > > as.vector(rbind(one, one)) > > } > > <environment: 0x000000000daaf1c0> > > > f1(8) > > [1] 1 2 1 2 3 4 3 4 5 6 5 6 7 8 7 8 > > > > Pat > > > > > > On 11/11/2013 12:11, Federico Calboli wrote: > >> Hi All, > >> > >> I am trying to create an index that returns something like > >> > >> 1,2,1,2,3,4,3,4,5,6,5,6,7,8,7,8 > >> > >> and so on and so forth until a predetermined value (which is obviously > >> even). I am trying very hard to avoid for loops or for loops front > ends. > >> > >> I'd be obliged if anybody could offer a suggestion. > >> > >> BW > >> > >> F > >> > >> > >> > >> ______________________________________________ > >> > > > R-help@ > > > 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. > >> > > > > -- > > Patrick Burns > > > pburns@.seanet > > > twitter: @burnsstat @portfolioprobe > > http://www.portfolioprobe.com/blog > > http://www.burns-stat.com > > (home of: > > 'Impatient R' > > 'The R Inferno' > > 'Tao Te Programming') > > > > ______________________________________________ > > > R-help@ > > > 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. > > > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/repeating-values-in-an-index-two-by-two-tp4680210p4680234.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. > [[alternative HTML version deleted]] ______________________________________________ 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.