[R] matrix position to list of coordinates

[Willi Richert]

Hi Ana,

> d=dim(A)
> d
[1] 2 4
> cbind(rep(1:d[1], each=d[2]), rep(1:d[2], d[1]))
     [,1] [,2]
[1,]    1    1
[2,]    1    2
[3,]    1    3
[4,]    1    4
[5,]    2    1
[6,]    2    2
[7,]    2    3
[8,]    2    4

Thanks,
wr


* Ana <rrasterr at gmail.com> [2012-01-01 23:21:12 +0100]:

> How can I extract a list of the positions in the matrix?
> > A=matrix(1:8, nrow=2,ncol=4)
> > A
>      [,1] [,2] [,3] [,4]
> [1,]    1    3    5    7
> [2,]    2    4    6    8
> 
> 
> Something like this
> 
> pos.A
> 
> 1 1
> 1 2
> 1 3
> 1 4
> 2 1
> 2 2
> 2 3
> 2 4
> 
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