I have a 12-D array and am using each dimension as an index value in an optimization problem.
A(:,:,i1,i2,i3,i4,i5,i6,i7,i8,i9,i10)
each index value i is a value from 1 to 5.
I want to sort A from greatest to least and keep track of the indices so I know which indices correspond to to what value of A.
So my ideal output would be a 2 column cell/array with one column being the value and the other other column being the index values.
For a simple 3D example: say I have a 3D array: A(:,:,i1).
Where:
A(:,:,1) = 2
A(:,:,2) = 6
A(:,:,3) = 13
A(:,:,4) = 11
A(:,:,5) = 5
I would like my output to be:
13 3
11 4
6 2
5 5
2 1
EDIT:
assume I have 1x1x3x3 sized input such that
A(1,1,1,1) = 3
A(1,1,2,1) = 1
A(1,1,3,1) = 23
A(1,1,1,2) = 12
A(1,1,2,2) = 9
A(1,1,3,2) = 8
A(1,1,1,3) = 33
A(1,1,2,3) = 14
A(1,1,3,3) = 6
the expected output would be:
33 [1,1,1,3]
23 [1,1,3,1]
14 [1,1,2,3]
12 [1,1,1,2]
9 [1,1,2,2]
8 [1,1,3,2]
6 [1,1,3,3]
3 [1,1,1,1]
1 [1,1,2,1]
This should be a generic code for any multi-dimensional input array -
%// Sort A and get the indices
[sorted_vals,sorted_idx] = sort(A(:),'descend');
%// Set storage for indices as a cell array and then store sorted indices into it
c = cell([1 numel(size(A))]);
[c{:}] = ind2sub(size(A),sorted_idx);
%// Convert c to the requested format and concatenate with cell arary version of
%// sorted values for the desired output
out = [num2cell(sorted_vals) mat2cell([c{:}],ones(1,numel(A)),numel(size(A)))];
The generic code owes its gratitude to this fine solution.