title: Filling upper area from area chart in python plotly
body: <p>I have an issue coloring a plotly area graph.</p>
  
  <p>My data is the following:</p>
  
  <pre><code> class1       class2      class3      class4
      0            0            0          0             
      0            0            1          1             
      1            0            0          3             
      0            0            0          2    
      0            0            0          2
      0            0            0          2
      0            0            0          2
      0            0            0          1
      0            0            0          1
      0            0            0          1
      0            0            0          1
      0            0            0          1
      0            0            0          2
  </code></pre>
  
  <p>And I'm painting it like this:</p>
  
  <pre><code>trace0 = dict(
          x = new_index,
          y = class1['num_users'],
          hoverinfo = 'x+y',
          mode = 'lines',
          line=dict(width=0.5,
                    color='rgb(58, 203, 215)'),
          stackgroup = 'one',
          name = '[1,{}] '.format(lower_q) ) 
  trace1 = dict(
          x = new_index,
          y = class2['num_users'],
          hoverinfo = 'x+y',
          mode = 'lines',
          line=dict(width=0.5,
                    color='rgb(177, 193, 123)'),
          stackgroup = 'one',
          name = '[{},{}] '.format(lower_q + 1, medium_q) ) 
  trace2 = dict(
          x = new_index,
          y = class3['num_users'],
          hoverinfo = 'x+y',
          mode = 'lines',
          line=dict(width=0.5,
                    color='rgb(243, 161, 203)'),
          stackgroup = 'one',
          name = '[{},{}] '.format(medium_q + 1, upper_q) ) 
  trace3 = dict(
          x = new_index,
          y = class4['num_users'],
          hoverinfo = 'x+y',
          mode = 'lines',
          line=dict(width=0.5,
                    color='rgb(184, 178, 247)'),
          stackgroup = 'one',
          name = '&gt;= {}'.format(upper_q + 1) ) 
  trace4 = dict(
          x = new_index,
          y = class4['num_users'],
          hoverinfo = 'x+y',
          mode = 'lines',
          line=dict(width=0.5,
                    color='rgb(178, 241, 247)'),
          stackgroup = 'one',
          name = 'upper area' )
  
      data = [trace0, trace1, trace2, trace3, trace4]
  </code></pre>
  
  <p>I just want to paint a <strong>filled area chart</strong> for the 4 columns of the dataframe, but note I added an extra trace, <code>trace4</code> in order to paint the upper area. The result I get is the following:
  <a href="https://i.stack.imgur.com/Yy7y6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Yy7y6.png" alt="enter image description here"></a></p>
  
  <p>But note that the expected output is that the blue upper area covers the whole upper part of the graph, like it does here:</p>
  
  <p><a href="https://i.stack.imgur.com/K7Ilg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/K7Ilg.png" alt="enter image description here"></a></p>
  
  <p>Any help on how to fill in the upper area of the graph will be welcome.</p>
  
  <p>Thank you very much in advance!</p>