title: Plotly: How to create faceted bar plots including a dropdown menu?
body: <p>I have the following dataframe</p>
  
  <pre><code>import pandas as pd
  df = pd.DataFrame({'var1':[0.2, 0.3, 0.4, 0.5, 0.6], 'var2': [1.2, 1.3, 1.4, 1.5, 1.6],
                     'facet_var': ['sd_1', 'sd_1', 'ctrl_1', 'ctrl_1', 'ctrl_1'],
                     'value_facet': ['a', 'b', 'a','b','c']})
  </code></pre>
  
  <p>I would like to create an <code>html</code> with <code>barplots</code> of <code>var1</code> and <code>var2</code> (selected from a dropdown menu) faceted by <code>facet_var</code>. The <code>x_values</code> of the barplots would be the <code>value_facet</code> and the <code>height</code> of the <code>barplots</code> would be the <code>var1</code> or <code>var2</code> depending on the selection from the dropdown menu</p>
  
  <p>Any ideas how to do something like that using <code>plotly</code> ?</p>