Computes the Hamming distance between two 1D arrays.
The Hamming distance between 1D arrays u and v, is simply the proportion of disagreeing components in u and v. If u and v are boolean vectors, the Hamming distance is
where is the number of occurrences of and for .
Parameters :  u : (N,) array_like
v : (N,) array_like


Returns :  hamming : double
