title: How do I element-wise square root a gonum matrix?
body: <p>I was going to use <code>Pow</code> but it only seems to accept powering by integer values.</p>
  
  <p>For example, the element-wise square root matrix <code>m</code> of matrix <code>a</code>.:</p>
  
  <pre><code>a = ⎡ 4   9⎤
      ⎣16  25⎦
  
  m = ⎡2  3⎤
      ⎣4  5⎦
  </code></pre>