title: ValueError: view limit minimum -35738.3640567 is less than 1 and is an invalid Matplotlib date value
body: <p>im a beginner in matplotlib. Im trying to plot a dataframe using matplotlib.pyplot. The problem is that everytime I try to plot it i get the following error:</p>
  
  <pre class="lang-py prettyprint-override"><code>ValueError: view limit minimum -35738.3640567 is less than 1 and is an invalid Matplotlib date value. This often happens if you pass a non-datetime value to an axis that has datetime units.
  
  </code></pre>
  
  <p>According to the error, it seems to be like theres a non-datetime value in the datetime column, but there isnt.</p>
  
  <p>Ive tried using pd.to_datetime() and try to change the format of the timestamp to <code>pd.to_datetime(df_google['datetime'], format = '%d/%m/%Y')</code> but nothing changes.</p>
  
  <p>This is the code im trying to use:</p>
  
  <pre class="lang-py prettyprint-override"><code>import matplotlib.pyplot as plt
  
  df_google.plot()
  plt.show()
  </code></pre>
  
  <p>df_google is a dataframe with columns <code>['datetime','price']</code> and some of the values are the following:</p>
  
  <pre class="lang-py prettyprint-override"><code>     datetime        price
  0  2018-05-15  1079.229980
  1  2018-05-16  1081.770020
  2  2018-05-17  1078.589966
  3  2018-05-18  1066.359985
  4  2018-05-21  1079.579956
  5  2018-05-22  1069.729980
  6  2018-05-23  1079.689941
  7  2018-05-24  1079.239990
  8  2018-05-25  1075.660034
  9  2018-05-29  1060.319946
  </code></pre>
  
  <p>Can someone try to help me understand this type of error? Why does it says theres a non-datetime value when every value is a datetime type value? How can I plot this dataframe?</p>