title: Sum of products of two arrays (dotproduct)
body: <p>First off, I know my title can be formulated better, but my math classes are so far gone I can't remember the correct words anymore..</p>
  
  <p>I need to do something like this (pseudo c#)</p>
  
  <pre><code>int[] digits1 = new int[10]{0,1,2,3,4,5,6,7,8,9};
  int[] digits2 = new int[10]{0,1,2,3,4,5,6,7,8,9};
  int result = digits1*digits2
  </code></pre>
  
  <p>This would be the sum of the product of element[i] of each array.</p>
  
  <p>This obviously doesn't work.
  Any suggestions towards either a better title or the solution?</p>
  
  <p><strong>EDIT</strong>
  clarification: I know I could loop them both and do the math.
  Basically I would think there is a better way to do this and I'm looking for it purely out of personal curiousity.</p>