# ind2sub output dimension

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Mohsen Davarynejad on 10 Dec 2011
My question is regarding the output of the ind2sub function. In my code, since the input dimention of ind2sub changes, i should expect the output dimention to change. But a code like this is not working.
B = rand(6,6,6);
A(1:ndims(B)) = ind2sub(size(B),56);
The output of the above code is [56 56 56] while I'm expecting something like [2 4 2].
Any suggestion?

Fangjun Jiang on 11 Dec 2011
B=rand(4,5,6);
Ind=(20:25).';
n=ndims(B);
Sub=cell(1,n);
[Sub{:}]=ind2sub(size(B),Ind)
SubMatrix=cell2mat(Sub)
Sub =
[6x1 double] [6x1 double] [6x1 double]
SubMatrix =
4 5 1
1 1 2
2 1 2
3 1 2
4 1 2
1 2 2
Mohsen Davarynejad on 11 Dec 2011
Thanks.

bym on 10 Dec 2011
you need multiple assignments for that function.
[r,c,p]=ind2sub(size(B),56)
r =
2
c =
4
p =
2
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Mohsen Davarynejad on 10 Dec 2011
But as I've mentioned, the output dimention is changing. So I do not know if the I need three variables, in your case r, c, p, of if I need more.