Is something like this what you have in mind?
m=. i. 2 3 4
indmak m
0 0 0
0 0 1
0 0 2
0 0 3
0 1 0
0 1 1
0 1 2
0 1 3
0 2 0
0 2 1
0 2 2
0 2 3
1 0 0
1 0 1
1 0 2
1 0 3
1 1 0
1 1 1
1 1 2
1 1 3
1 2 0
1 2 1
1 2 2
1 2 3
indmak
(#: i.)@$
On 2015.04.04 23:09:58, you,
the extraordinary Sergeif, spake thus:
> Hi.
>
> How can someone create list of indexes of 3d table (N x M x K)?
>
> I have written this simple code:
>
> ind3d =: 3 : 0
> 'n m k' =. y
> p0 =. k&|
> p1 =. (m&|)@:<.@:(%&k)
> p2 =. <.@:(%&(m*k))
> (p2 , p1 , p0)"0 (i. (n*m*k))
> )
>
> but it's very very slow. Does any tacit solution for this problem exist?
>
> Another question is how to fill the table with values depending on indexes
> of cell? For example, F[i,j,k] = (i * j) - (i * k) + (j * k).
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--
Nollaig MacKenzie
http://www.yorku.ca/nollaig
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