IndToCoord.m

% coords = IndToCoord(arraySize, arrayIdx)
%   This function will take a list of indices and convert them into a
%   coordinate with the same dimentionality of the array size in.

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function coords = IndToCoord(arraySize, arrayIdx)
    coords = zeros(length(arrayIdx),length(arraySize));

    linSize = [1 cumprod(arraySize)];
    partialIdx = arrayIdx;
    for i = length(arraySize):-1:1
        r = rem(partialIdx-1, linSize(i)) + 1;
        q = floor((partialIdx-r) / linSize(i)) + 1;

        coords(:,i) = q;
        partialIdx = r;
    end
end