> m <- matrix(rpois(16, 10), ncol = 4)
> m
[,1] [,2] [,3] [,4]
[1,] 9 12 8 11
[2,] 12 7 11 8
[3,] 12 7 8 8
[4,] 11 11 4 8> apply(m, 2, sort)
[,1] [,2] [,3] [,4]
[1,] 9 7 4 8
[2,] 11 7 8 8
[3,] 12 11 8 8
[4,] 12 12 11 11> apply(m, 2, order)
[,1] [,2] [,3] [,4]
[1,] 1 2 4 2
[2,] 4 3 1 3
[3,] 2 4 3 4
[4,] 3 1 2 1
HTH,
Dennis
On Tue, Oct 11, 2011 at 7:05 PM, Wendy <wendy2.qiao at gmail.com>
wrote:> Hi all,
>
> I have matrix, A. I want to sort the elements in each column in a ascending
> order and output the index number their position. For example
>
> A >
> ? ? ? ? ?[,1] ? ? [,2] ? ? ?[,3] ? ? ? [,4]
> [1,] 135.87060 97.55820 121.07722 171.625495
> [2,] ?70.19811 36.64529 ?50.13501 ? 6.319125
> [3,] ?26.86293 24.22025 ?43.42826 ?26.952587
> [4,] ? 1.88864 54.97618 ?12.50913 103.958836
>
> I want the output, B, to be
>
> B >
> ? ? [,1] [,2] [,3] [,4]
> [1,] ? ?4 ? ?4 ? ?4 ? ?4
> [2,] ? ?3 ? ?2 ? ?3 ? ?1
> [3,] ? ?2 ? ?1 ? ?2 ? ?2
> [4,] ? ?1 ? ?3 ? ?1 ? ?3
>
> I tried "apply(test,1,order)", but it did not work. Could anybody
please
> help? Thank you very much.
>
> Wendy
>
>
> --
> View this message in context:
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> Sent from the R help mailing list archive at Nabble.com.
>
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