Hi, You could also try: set.seed(51) mat1<-matrix(sample(1:5000,1116*12,replace=TRUE),nrow=1116) dim(mat1) #[1] 1116 12
res1<-lapply(split(as.data.frame(mat1),rep(1:36,each=31)),as.matrix) unlist(lapply(res1,nrow)) # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 #31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 #27 28 29 30 31 32 33 34 35 36 #31 31 31 31 31 31 31 31 31 31 A.K. ----- Original Message ----- From: "MacQueen, Don" <macque...@llnl.gov> To: eliza botto <eliza_bo...@hotmail.com>; "r-help@r-project.org" <r-help@r-project.org> Cc: Sent: Thursday, January 3, 2013 11:56 AM Subject: Re: [R] splitting matrices This example illustrates a method that may do what you want. ## split a 20x5 matrix into five 4x5 matrices xmat <- matrix(1:100, nrow=20, ncol=5, byrow=TRUE) xsplit <- rep( 1:5, times= rep(4,5)) tmp <- split.data.frame(xmat,xsplit) You will need to change xsplit to fit your dimensions. -Don -- Don MacQueen Lawrence Livermore National Laboratory 7000 East Ave., L-627 Livermore, CA 94550 925-423-1062 On 1/3/13 8:40 AM, "eliza botto" <eliza_bo...@hotmail.com> wrote: > > >Dear useRs, >i want to split a matrix having 1116rows and 12 columns. i want to split >that matrix into 36 small matrices each having 12 columns and 31 rows. >The big matrix should be splitted row wise. which means that the first >small matrix should copy values which are in first 31 rows and 12 columns >of the big matrix. similarly 2nd small matrix should contain values from >32nd to 63rd row of the big matrix and so on. on the whole i want to have >36 small matrices.i tried >dim(dd) <- c(31,12,35) >but the result are not stisfactory... >thanks in advance >elisa > [[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. ______________________________________________ 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. ______________________________________________ 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.
