[R] Multiplying elements of a list by rows of a matrix

[Rui Barradas]

Hello,

Thanks for the data example. Try

lapply(seq_along(X), function(i) tt[i,] %*% X[[i]])

Hope this helps,

Rui Barradas
Em 11-11-2012 16:33, Clemontina Davenport escreveu:
> Hi all,
> I have the following code:
>
> set.seed(1)
> x1 <- matrix(sample(1:12), ncol=3)
> x2 <- matrix(sample(1:12), ncol=3)
> x3 <- matrix(sample(1:12), ncol=3)
> X <- list(x1,x2,x3)
> tt <- matrix(round(runif(5*4),2), ncol=4)
>
> Is there a way I can construct a new list where
> newlist[[i]] = tt[i,] %*% X[[i]]
> without using a for loop? Each element of newlist will be 3 x 1 vector.
>
> Thanks
> --
> Tina Alexander
>
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