title: Check for duplicate entries in a large matrix matlab
body: <p>I have a very large matrix (901x1801) which I generated by combining values of three similar arrays (with repeated values in them) to generate unique codes using a mathematical expression. The matrix is filled with these codes.</p>
  
  <p>My question is... How can I check that each values of the matrix (901x1801) is unique and not repeating even a single time?</p>
  
  <p>Or...
  Can anyone tell me how can I generate a matrix by combining three arrays of similar elements in a way that each generated value will be unique.  </p>
  
  <p>an early reply will be greatly appciable.
  Thanks in advance.</p>