title: plotting a number of specific lines in python
body: <p>In my plot the x-axis contains dates, but i want to limit it so that they can start from a certain date and not consider the first years of my data 
  I have tried this:</p>
  
  <pre><code>plt.figure
  f_linear=interp1d(datasurf.iloc[:,0],datasurf.iloc[:,1])
  plt.plot(datasurf.iloc[:,0],datasurf.iloc[:,1], label='Surface level')
  plt.xlim(pd.Timestamp('2016-01-01'), pd.Timestamp('2019-09-14'))
  plt.xlabel('Date')
  plt.ylabel('Lake level(m)')
  plt.legend()
  </code></pre>
  
  <p>but I have this error:
  Failed to convert value(s) to axis units: Timestamp('2016-01-01 00:00:00')</p>
  
  <p>Can someone suggest me something else please </p>