Re: [R] loop for column substraction of a matrix

2012-10-05 Thread Rui Barradas
Or, using your mapply solution, compute rs <- rowSums(mat1) and then use it for all subtractions. With a larger dataset this would be probably faster. Rui Barradas Em 05-10-2012 22:41, arun escreveu: Hi, Sorry, I think I misunderstand your question (after reading Rui's solution). You can a

Re: [R] loop for column substraction of a matrix

2012-10-05 Thread eliza botto
Dear Arun and Barradas, millions of thanks. you guys always rock. regards eliza > Date: Fri, 5 Oct 2012 14:41:38 -0700 > From: smartpink...@yahoo.com > Subject: Re: [R] loop for column substraction of a matrix > To: eliza_bo...@hotmail.com > CC: ruipbarra...@sapo.pt; r-help@r-proj

Re: [R] loop for column substraction of a matrix

2012-10-05 Thread arun
Hi, Sorry, I think I misunderstand your question (after reading Rui's solution). You can also try any of these to get the result if this is what you meant: set.seed(1) mat1<-matrix(sample(1:500,380,replace=TRUE),ncol=38) res1<-t(do.call(rbind,lapply(1:ncol(mat1), function(i) mat1[,i]-apply(mat1,

Re: [R] loop for column substraction of a matrix

2012-10-05 Thread arun
HI, Try this: set.seed(1)  mat1<-matrix(sample(1:500,380,replace=TRUE),ncol=38) list1<-list() for(i in 1:ncol(mat1)){  list1[[i]]<-t(apply(mat1,1,function(x) x[i]-x))  list1} list1 A.K. - Original Message - From: eliza botto To: "r-help@r-project.org" Cc: Sent: Friday, October 5, 20

Re: [R] loop for column substraction of a matrix

2012-10-05 Thread Rui Barradas
Hello, 1. Let me refrase it a bit. For each column, sum all others and take the symmetric. mat <- matrix(1:30, ncol = 3) sapply(seq_len(ncol(mat)), function(i) -rowSums(mat[, -i])) 2. write.table (maybe using sep = "\t" ?) and send the file to printer. Hope this helps, Rui Barradas Em 05