[R] Column wise matrix multiplication

[Dimitris Rizopoulos]

Try

apply(A, 1, prod)


I hope it helps.

Best,
Dimitris


On 2/20/2012 4:21 PM, Graziano Mirata wrote:
> Hi all,
> I am trying to multiply each column of a matrix such to have a unique resulting vector with length equal to the number of rows of the original matrix. In short I would like to do what prod(.) function in Matlab does, i.e.
>
> A<-matrix(c(1:10),5,2)
>
> V = A[,1]*A[,2]
>
> Thank you
>
> Graziano
>
>
>
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-- 
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center

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