title: Python: Split NumPy array based on values in the array
body: <p>I have one big array:</p>
  
  <pre><code>[(1.0, 3.0, 1, 427338.4297000002, 4848489.4332)
   (1.0, 3.0, 2, 427344.7937000003, 4848482.0692)
   (1.0, 3.0, 3, 427346.4297000002, 4848472.7469) ...,
   (1.0, 1.0, 7084, 427345.2709999997, 4848796.592)
   (1.0, 1.0, 7085, 427352.9277999997, 4848790.9351)
   (1.0, 1.0, 7086, 427359.16060000006, 4848787.4332)]
  </code></pre>
  
  <p>I want to split this array into multiple arrays based on the 2nd value in the array (3.0, 3.0, 3.0...1.0,1.0,10). </p>
  
  <p>Every time the 2nd value changes, I want a new array, so basically each new array has the same 2nd value. I've looked this up on Stack Overflow and know of the command </p>
  
  <pre><code>np.split(array, number)
  </code></pre>
  
  <p>but I'm not trying to split the array into a certain number of arrays, but rather by a value. How would I be able to split the array in the way specified above?
  Any help would be appreciated!</p>