[R] maximum over one dimension of a 3-dimensional array

[eric lee]

Hi,

I'm running R 2.7.2 on windows XP.  I'd like to find the maximum of a
3-d array over it's third index to create a 2-d array.  For example:

> x <- array(c(1,2,3,10,11,12,3:8),c(2,3,2))
> x
, , 1

     [,1] [,2] [,3]
[1,]    1    3   11
[2,]    2   10   12

, , 2

     [,1] [,2] [,3]
[1,]    3    5    7
[2,]    4    6    8

> x1 <- x[,,1]
> x2 <- x[,,2]
> pmax(x1,x2)
     [,1] [,2] [,3]
[1,]    3    5   11
[2,]    4   10   12

Is there a pre-defined function that I can use to do this without
using a for-loop?  Also, the third index can be long and of variable
length, so I don't want to explicitly write out x1, x2,...  Thanks in
advance for your help.

eric