# Partition a vector into select groups with fixed length

5 messages
Open this post in threaded view
|

## Partition a vector into select groups with fixed length

 Hi, Let say I have a vector as below Vec = LETTERS Now I want to break this vector into groups of the same length of 5. So, 1st group consists - "A" "B" "C" "D" "E" 2nd group - "F" "G" "H" "I" "J" and so on.. last group will consist only the leftover elements I have a very large initial vector, so looking for some efficient way to achieve the same. Any pointer will be highly appreciated. Thanks for your time. ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
Open this post in threaded view
|

## Re: Partition a vector into select groups with fixed length

 Hello, The following function will do it. It uses a standard cumsum trick to create a break vector f. And predicts special cases (n = 0 or n = 1). breakVec <- function(x, n = 5){    if(n < 1) stop(paste("Illegal value n:", n))    if(n == 1){      f = ""    }else{      f <- c(1, rep(0, n - 1))      f <- rep(f, length.out = length(x))      f <- cumsum(f)    }    split(x, f) } breakVec(LETTERS) breakVec(LETTERS, 4) breakVec(LETTERS, 1) breakVec(LETTERS, -1) Hope this helps, Rui Barradas Às 19:01 de 18/08/19, Christofer Bogaso escreveu: > Hi, > > Let say I have a vector as below > > Vec = LETTERS > > Now I want to break this vector into groups of the same length of 5. > > So, > 1st group consists - "A" "B" "C" "D" "E" > 2nd group - "F" "G" "H" "I" "J" > > and so on.. > last group will consist only the leftover elements > > I have a very large initial vector, so looking for some efficient way > to achieve the same. Any pointer will be highly appreciated. > > Thanks for your time. > > ______________________________________________ > [hidden email] 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. > ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
Open this post in threaded view
|

## Re: Partition a vector into select groups with fixed length

 In reply to this post by Bogaso Hi, Christofer, try something along len <- 5 split(Vec, rep(seq(ceiling(length(Vec)/len)), each = len))   Hth  --  Gerrit --------------------------------------------------------------------- Dr. Gerrit Eichner                   Mathematical Institute, Room 212 [hidden email]   Justus-Liebig-University Giessen Tel: +49-(0)641-99-32104          Arndtstr. 2, 35392 Giessen, Germany Fax: +49-(0)641-99-32109            http://www.uni-giessen.de/eichner--------------------------------------------------------------------- Am 18.08.2019 um 20:01 schrieb Christofer Bogaso: > Hi, > > Let say I have a vector as below > > Vec = LETTERS > > Now I want to break this vector into groups of the same length of 5. > > So, > 1st group consists - "A" "B" "C" "D" "E" > 2nd group - "F" "G" "H" "I" "J" > > and so on.. > last group will consist only the leftover elements > > I have a very large initial vector, so looking for some efficient way > to achieve the same. Any pointer will be highly appreciated. > > Thanks for your time. > > ______________________________________________ > [hidden email] 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. > ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.