Pete Brecknock
2011-Apr-29 13:06 UTC
[R] Element by Element addition of the columns of a Matrix
... is the apply function what you are looking for? A=matrix(1,2,4) apply(A,1,sum) HTH Pete -- View this message in context: http://r.789695.n4.nabble.com/Element-by-Element-addition-of-the-columns-of-a-Matrix-tp3483545p3483628.html Sent from the R help mailing list archive at Nabble.com.
Uwe Ligges
2011-May-01 16:11 UTC
[R] Element by Element addition of the columns of a Matrix
On 29.04.2011 15:06, Pete Brecknock wrote:> ... is the apply function what you are looking for? > > A=matrix(1,2,4) > > apply(A,1,sum)Thanks for providing answers to R-help, but: 1. Please quote the original question for the mailing list readers of us. 2. Please reply also to the original poster who may not be subscribed to the list. 3. In order to do the above more efficient, you actually want to use rowSums(A) rather than the apply() version given above. Best, Uwe Ligges> HTH > > Pete > > > > > -- > View this message in context: http://r.789695.n4.nabble.com/Element-by-Element-addition-of-the-columns-of-a-Matrix-tp3483545p3483628.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at 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.