bex
2014-Feb-25 20:09 UTC
[R] R: Re: how to extract consecutive subvetors of different lengths from an existing vector and create a matrix
Thank you Arun! Le mail ti raggiungono ovunque con BlackBerry® from Vodafone! -----Original Message----- From: "arun kirshna [via R]" <ml-node+s789695n4685806h49@n4.nabble.com> Date: Tue, 25 Feb 2014 10:54:10 To: bex<elisabetta.petracci@gmail.com> Subject: Re: how to extract consecutive subvetors of different lengths from an existing vector and create a matrix Hi, One way would be: res <- t(sapply(split(y,rep(seq_along(n),n)),function(x) {if(length(x) < max(n)) c(x,rep(NA,max(n)-length(x))) else x})) A.K. Dear all, my question regards how to subset an existing vector in subvectors of different lengths and then create a matrix. See example below. I have vectors: y<-c(1,1,1,0,0,1,1) n<-c(3,2,2) and I'd like to create the matrix A of the following form: 1 1 1 0 0 NA 1 1 NA I'd like to "cut" y sequentially based on information in vector n, that is, generating 3 subvectors (the first with the first 3 elements of y, the second with the other 2 elements of y, and the last one with the latter 2 elements of y) and creating a matrix A (with dimensions, no.of rows=length(n), no. of col=max(n) and including NAs where necessary. Hope to have been clear. Bex ______________________________________________ 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. _______________________________________________ If you reply to this email, your message will be added to the discussion below: http://r.789695.n4.nabble.com/how-to-extract-consecutive-subvetors-of-different-lengths-from-an-existing-vector-and-create-a-matrix-tp4685783p4685806.html To unsubscribe from how to extract consecutive subvetors of different lengths from an existing vector and create a matrix, visit http://r.789695.n4.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=4685783&code=ZWxpc2FiZXR0YS5wZXRyYWNjaUBnbWFpbC5jb218NDY4NTc4M3w4ODEyMDMyNDg -- View this message in context: http://r.789695.n4.nabble.com/R-Re-how-to-extract-consecutive-subvetors-of-different-lengths-from-an-existing-vector-and-create-a-x-tp4685820.html Sent from the R help mailing list archive at Nabble.com. [[alternative HTML version deleted]]