title: What does operator "dot" (.) mean?
body: <p>Given the code  :</p>
  
  <pre><code> A = [1 2 3; 3 2 1]
   B = A.^2
  </code></pre>
  
  <p>The output : </p>
  
  <pre><code>B =
  
       1     4     9
       9     4     1
  </code></pre>
  
  <p>But if I do this : <code>B = A^2</code></p>
  
  <p>The output is :</p>
  
  <pre><code>Error using  ^ 
  Inputs must be a scalar and a square matrix.
  To compute elementwise POWER, use POWER (.^) instead.
  </code></pre>
  
  <p>What does the operator <code>.</code> do exactly ? </p>