title: Can I use a numpy array to generate folds for cross validation?
body: <p>I would like to use a numpy array to build folds for a k-folds cross validation task. Taking out the test slice is easy, but I can't figure out how to return the remainder of the array, with the test slice omitted.  Is there an efficient way to do this?</p>
  
  <pre><code>examples = range(50)
  classes = range(50)
  data = np.array(zip(classes,examples))
  test_slice = data[5:10]
  train_on_remainder = ??
  </code></pre>