MATLAB: How to find the number of occurrences of NaN and the corresponding subscripts in an array

arraynannumber of occurencesubscripts

A = NaN 100 101 102 103 104
    201 2   7   3   2   2 
    202 NaN 8   4   5   6
    203 NaN NaN 2   3   5
    205 3   4   2   6   4
I have a matrix with the first row and first column being headers. I would like to know the no. occurences and subscripts on NaN.
To find no. of occurences, I did
number_of_nan = sum(sum(isnan(A(2:end,2:end))))
Also,
    logical_array = isnan(A(2:end,2:end));
    numel(logical_array(logical_array == 1));
Is there a simpler/better way. Also how do I find the subscripts of the NaN elements in the array ?

Best Answer

Another option:
 logical_array = A(2:end,2:end) ~= A(2:end,2:end)
 num_NaN = sum(logical_array(:));
 idx = find(logical_array); %I am not sure this is what you want, please see my comment to your question
EDIT so that was not what your wanted after all. For that:
To get row and column position, according to the header:
 logical_array = A(2:end,2:end) ~= A(2:end,2:end)
 idx = find(logical_array); 
 [dim(1) dim(2)] = size(A);
 [ii,jj] = ind2sub(dim-1,idx);
 your_position = [A(ii+1,1) A(1,jj+1)'];
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