title: Multiple layer heatmap in seaborn?
body: <p>I have a dataframe with 3 columns. Each of the columns contains some "labels". I want to study a correspondence between the labels of the three columns. As such, I created 3 heatmaps, for each pair of columns, that shows the number of times a pair of labels has appeared. </p>
  
  <p>For example: </p>
  
  <pre><code>colA  | colB  | colC
  
  dog     car     USA
  cat     plane   Germany
  fish    truck   Spain
  eagle   bike    France
  dog     car     USA
  eagle   train   UK
  </code></pre>
  
  <p>A heat map of the first two columns above is: </p>
  
  <pre><code>dog      2     0     0     0     0
  cat      0     1     0     0     0
  fish     0     0     1     0     0
  eagle    0     0     0     1     1
          car  plane truck bike train
  </code></pre>
  
  <p>Now, in the same manner, I can create the other two heatmaps. My question is, can I combine two of them (for example keeping the horizontal axis the same and adding two vertical axes, for the other two columns) create a heatmap that includes the entire triplet correspondence? </p>
  
  <p>Sorry if my question seems a bit vague, but I am trying to see if there are ways of visualizing a three-way correspondence in the style of a heatmap. </p>