[R] extract cells by columns/rows from matrix

[Jannis]

which(data==max(data),arr.ind=TRUE)

gives you the indices of the largest element.

which(data==data[order(data)[2]],arr.ind=TRUE)

the indices of the second largest.

Best
Jannis

On 04/14/2011 10:23 PM, Nicolas Gutierrez wrote:
> hi All,
>
> I have a matrix Ufi (x by y)
>
>   1  2  3  4  5
> 1 0  0  0  0  3
> 2 0  0  0  9  0
> 3 0  2  0  0  3
> 4 0  0  1  0  0
> 5 0  1  0  0  0
>
> And I need the x and y "coordinates" of those cells with maximum values:
>
> First:
>
> x=4; y=2  (Value=9)
>
> Second:
>
> x=5; y=3  (value=3)
>
> Any help?
> THANKS!
>
> Nic
>
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