title: Matlab: How do you implement this sum?
body: <p>I need to implement the following:</p>
  
  <pre><code>x_i = e ^ (-1 - sum (y_j * A_ji))
  </code></pre>
  
  <p>where <code>i = 1..10</code>, <code>j = 1..5</code> and <code>A</code> is a 5x10 matrix (randomly generated).</p>
  
  <p>I tried using <code>symsum</code> but it gave me an index error. Could someone please help me figure out how to implement this?</p>