Effectively you want a circulant matrix but filled by column. Example input vector and number of columns
x = c(1:8,19:20) nc = 5 For the result you specifically describe, the following generalises for any vector and any arbitrary number of columns 'nc', padding with zeros as necessary. matrix(c(rep(c(x,rep(0,nc)),nc-1),x), ncol=nc) For the unpadded column circulant on the same inputs nx = length(x) ind = 1+ outer(0:(nx-1),0:(1-nc),'+') %% nx matrix(x[ind], ncol=nc) Cheers > On 6 Mar 2017, at 16:18, Peter Thuresson <peter.thures...@umea.se> wrote: > > Hello, > > Is there a function in R which can transform, let say a vector: > > c(1:4) > > to a matrix where the vector is repeated but "projected" +1 one step down for > every (new) column. > I want the output below from the vector above, like this: > > p<-c(1,2,3,4,0,0,0,0,1,2,3,4,0,0,0,0,1,2,3,4,0,0,0,0,1,2,3,4) > > matrix(p,7,4) > > best regards / Peter > > [[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.
