MATLAB: Ind2sub doesn’t work

ind2sub

Check it out:
>> A = zeros(3);
>> A(2,3) = 1 
A =
     0     0     0
     0     0     1
     0     0     0
>> tmp = A'
tmp =
     0     0     0
     0     0     0
     0     1     0
>> [maxVal, maxInd] = max(tmp(:))  
maxVal =
     1
maxInd =
     6
And now the WTF comes:
>> ind2sub(size(tmp), maxInd)
ans =
     6
>> ind2sub(maxInd, size(tmp))
ans =
     3     3
Seems like function is dead.

Best Answer

You are funny.
ind2sub reshapes the siz first argument to match the number of output variables used (in your case a single output argument), so that the resulting subscripts suffice to fully index the original elements. In your case:
 ind2sub(size(tmp), maxInd)
is just the same as:
 ind2sub(numel(tmp), maxInd)
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