title: Python: numpy.insert NaN value
body: <p>I'm trying to insert <code>NaN</code> values to specific indices of a numpy array. I keep getting this error:</p>
  
  <p>TypeError: Cannot cast array data from dtype('float64') to dtype('int64') according to the rule 'safe'</p>
  
  <p>When trying to do so with the following code.</p>
  
  <pre><code>x = np.array(range(1,11))
  x = np.insert(x, 5, np.nan, axis=0)
  </code></pre>
  
  <p>However, I can append <code>NaN</code> values to the end of the array with no problem.</p>
  
  <pre><code>x = np.array(range(1,11))
  x = np.append(x, np.nan)
  </code></pre>
  
  <p>Why is this and how can I insert NaN values in my array?</p>