Hi Anh, If I undestarstand:
# Your matrix set.seed(123) mat<-matrix(cbind(rnorm(20),rnorm(20)), ncol = 2) # Scale (mat-apply(mat[1:5,],2,mean))/apply(mat[1:5,],2,sd) HTH, Jorge On Fri, May 9, 2008 at 3:51 PM, Anh Tran <[EMAIL PROTECTED]> wrote: > Hi, > Let say I have this matrix: > > > mat<-matrix(cbind(rnorm(20),rnorm(20)), ncol = 2) > > And I want to rescale values of column [,1] and [,2] using values from row > 1 > to 5, such that the values of row 1:5 should be rescale to the same > amplitude (kinda like take the z-score of population from row 1:5). column > 1 > and 2 are two different samples need to be compared. > > I hope I made myself clear enough. thanks for any help > > UCLA Neurology Research > > -- > Regards, > Anh Tran > > [[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. > [[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.