title: Adding an array to a numpy array
body: <p>I'd like to have a numpy array that looks something like this:</p>
  
  <pre><code>X = np.array([[10, 20], [20, 25], [30, 16], [40, 18], [50, 90], [60, 87]])
  </code></pre>
  
  <p>I currently have dictionary values that I retrieve from firestore:</p>
  
  <pre><code>doc_ref = db.collection('CPU Logs')
  query_ref = doc_ref.where(u'testData', u'==', True).order_by(u'logId')
  docs = query_ref.get()
  </code></pre>
  
  <p>I loop through them and assign the key values to 2 variables, <code>id</code> and <code>usage</code>, before adding them to an array <code>toAppend</code>:</p>
  
  <pre><code>for doc in docs:
      values = doc.to_dict()
      id = values['logId']
      usage = values['usage']
      toAppend = [id, usage]
  </code></pre>
  
  <p>toAppend would look something like <code>[10, 30]</code> if the id were 10 and the usage were 30. Now, I'm having trouble trying to add it to an empty numpy array. I've tried inserting:</p>
  
  <pre><code>X = np.array([])
  for doc in docs:
      values = doc.to_dict()
      id = values['logId']
      usage = values['usage']
      toAppend = [id, usage]
      a = X.flatten()
      np.insert(a, [0,0], toAppend)
  
  print(X)
  </code></pre>
  
  <p>as well as appending:</p>
  
  <pre><code>np.append(X, toAppend)
  </code></pre>
  
  <p>But both don't seem to work, as the print statement just prints out <code>[]</code>.</p>