MATLAB: Using array values as indices for inserting values into a larger destination array

MATLABmatrix indexing

Hello all,
I have 3 arrays, one containing row indices, one containing column indices, and one containing the corresponding value at the matching row and column location.
I am trying to use the indices arrays to place the corresponding values into a larger array at the locations specified by the row and column indices arrays.
Here is a simplified example:
rowIndices = magic(8);
colIndices = magic(8);
values = 1:8;
values = repmat(values',1,8);
destinationArray = zeros(max(rowIndices(:)),max(colIndices(:)));
Basically, values(1,1) should be placed into destinationArray at rowIndices(1,1), colIndices(1,1) but for all (row,col,val) combinations at once.
I am using a quite large dataset and am trying to avoid loops whenever possible so I was hoping there is an efficient way to do this with a limited number of operations.
Thank you for your time and if you can help I'll acknowledge you in my dissertation!
-Chris H.

Best Answer

Use sub2ind:
N = 8;
R = randi(9,N); % more interesting than MAGIC.

C = randi(9,N); % more interesting than MAGIC.
V = reshape(1:N*N,N,N); % non-repeating example values.
S = [max(R(:)),max(C(:))];
Z = zeros(S);
Z(sub2ind(S,R,C)) = V
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