R help - Jun 2003 - simple matrix question

what is the easiest way to get from 
> x
     x1 x2
[1,]  2  3
[2,]  3  2
[3,]  1  3
[4,]  1  4

the matrix xbar
> xbar1
       x1 x2
[1,] 1.75  3
[2,] 1.75  3
[3,] 1.75  3
[4,] 1.75  3

with the mean of the columns of x as values?

thanks

christoph

-- 
Christoph Lehmann <lehmann at puk.unibe.ch>
University Hospital of Clinical Psychiatry

Hoi Christoph,

--On woensdag 4 juni 2003 15:21 +0200 Christoph Lehmann 
<lehmann at puk.unibe.ch> wrote:
> what is the easiest way to get from
> x
>      x1 x2
> [1,]  2  3
> [2,]  3  2
> [3,]  1  3
> [4,]  1  4
>
> xbar1
>        x1 x2
> [1,] 1.75  3
> [2,] 1.75  3
> [3,] 1.75  3
> [4,] 1.75  3
>
> with the mean of the columns of x as values?
>
xbar1 <- tapply(as.vector(x), gl(2,4), mean);



-- 
Paul Lemmens
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--On woensdag 4 juni 2003 15:21 +0200 Christoph Lehmann 
<lehmann at puk.unibe.ch> wrote:
> what is the easiest way to get from
> x
>      x1 x2
> [1,]  2  3
> [2,]  3  2
> [3,]  1  3
> [4,]  1  4
>
> xbar1
>        x1 x2
> [1,] 1.75  3
> [2,] 1.75  3
> [3,] 1.75  3
> [4,] 1.75  3
>
> with the mean of the columns of x as values?
xbar <- predict(lm(x ~ 1))