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(mat1,1,sum)))) #or res1<-sapply(1:ncol(mat1), function(i) mat1[,i]-apply(mat1,1,sum)) #or res1<-mapply(FUN=function(i) mat1[,i]-rowSums(mat1), 1:ncol(mat1)) A.K ----- Original Message ----- From: eliza botto <eliza_bo...@hotmail.com> To: "r-help@r-project.org" <r-help@r-project.org> Cc: Sent: Friday, October 5, 2012 4:05 PM Subject: [R] loop for column substraction of a matrix Dear useRs, I have a matrix with 38 columns and 365 rows. what i want to do is the following..... 1. subtracting from each column, first itself and then all the remaining columns. More precisely, from column number 1, i will first subtract itself(column 1) and then the remaining 37 columns. Afterwards i will take column number 2 and do the same. In this way i want to proceed till 38th column. 2. i want to print the resulting matrix on A4 paper. Bundle of thanks in advance. best regards eliza [[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.
