title: ValueError for comparison of np.arrays
body: <p>I have a list of lists of np.arrays, representing islands > island > geodesic point on the island.</p>
  
  <p>I'm trying to use:</p>
  
  <pre><code>if not groups:
      createNewGroup(point)
  else:
      for group in groups:
          if point in group:
              continue
      else:
          createNewGroup(point)
  </code></pre>
  
  <p>The first island is being created correctly, but for the second island I am getting this error:</p>
  
  <pre><code>File "A2.py", line 371, in findIslands
  if point in group:
  ValueError: The truth value of an array with more than 
  one element is ambiguous. Use a.any() or a.all()
  </code></pre>
  
  <p>I've researched this error and am trying to understand how this applies to my situation, and have tried applying <code>.any()</code> and <code>.all()</code> to <code>point</code> but I am getting the same error regardless.</p>
  
  <p>I'm trying to check if the current geodesic point is already in the list of lists for any of the islands.  Point is multidimensional and I think that's where the issue is coming from.</p>