[R] Multiple Vector with matrix in R

[Rui Barradas]

Hello,

Try the following.

t(sapply(seq_along(w), function(i) mat1[i,]*w[i]))

Hope this helps,

Rui Barradas
Em 16-11-2012 16:34, frespider escreveu:
> Hi
>
> Can someone show me an easy way to multiple a weighted vector with an
> matrix?
>
> example below
> mat1<-matrix(sample(1:100,80,replace=TRUE),ncol=8)
> w <- 1/1:10
>
> I want the first element in w to be multiplied by the first row of mat1 and
> 2nd element in w to be multiplied with the 2nd row and so on.
>
> I have huge matrix is there an easy way other than diag(w)%*%mat1
>
> Thanks
>
>
>
> --
> View this message in context: http://r.789695.n4.nabble.com/Multiple-Vector-with-matrix-in-R-tp4649764.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.