HI, In addition to ?sweep(), you can use apply(-mat,1,`+`,x)
#or library(plyr) aaply(-mat,1,"+",x) A.K. ----- Original Message ----- From: C W <tmrs...@gmail.com> To: Sarah Goslee <sarah.gos...@gmail.com> Cc: r-help <r-help@r-project.org> Sent: Wednesday, December 5, 2012 1:51 PM Subject: Re: [R] data manipulation between vector and matrix Thanks, Sarah. First time heard about sweep(), it worked just the way I wanted. Mike On Wed, Dec 5, 2012 at 1:42 PM, Sarah Goslee <sarah.gos...@gmail.com> wrote: > Hi, > > On Wed, Dec 5, 2012 at 1:30 PM, C W <tmrs...@gmail.com> wrote: > > Dear list, > > I was curious how to subtract a vector from matrix? > > > > Say, I have > > > > mat <- matrix(1:40, nrow=20, ncol=2) > > > > x <-c(1,2) > > Thanks for the actual reproducible example. > > > I want, > > > > x-mat[1,] and x-mat[2,], and so on... Basically, subtract column elements > > of x against column elements in mat. > > > > But x-mat won't do it. > > This will (note the modification to get x - mat): > > sweep(-mat, 2, x, "+") > [,1] [,2] > [1,] 0 -19 > [2,] -1 -20 > [3,] -2 -21 > [4,] -3 -22 > [5,] -4 -23 > etc. > > -- > Sarah Goslee > http://www.functionaldiversity.org > [[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.
