Finding list of positions in multidimensional structure (array)

Question

Suppose I have a simple multidimensional structure, like this one:

somestr<-array(sample.int(2, 120, replace=TRUE), dim=c(4,5,6))

I\'m l

Answer 1

I think the which function can do that:

which(somestr==2, arr.ind=TRUE)

(if I understood everything correctly)

R> set.seed(123)
R> somestr <- array(sample.int(2, 120, replace=TRUE), dim=c(4,5,6))
R> somestr
, , 1

     [,1] [,2] [,3] [,4] [,5]
[1,]    1    2    2    2    1
[2,]    2    1    1    2    1
[3,]    1    2    2    1    1
[4,]    2    2    1    2    2

...

, , 6

     [,1] [,2] [,3] [,4] [,5]
[1,]    2    1    1    1    2
[2,]    1    2    1    2    2
[3,]    1    2    2    2    2
[4,]    2    2    1    1    1

R> which(somestr==2, arr.ind=TRUE)
      dim1 dim2 dim3
 [1,]    2    1    1
 [2,]    4    1    1
 [3,]    1    2    1
 [4,]    3    2    1
 [5,]    4    2    1
...
[57,]    2    5    6
[58,]    3    5    6