title: Adjacency Matrix from source target dataset
body: <p>I have a dataset as follows</p>
  
  <pre><code>Var1   Var2   Count
  A       B      3
  A       C      4
  A       D      10
  A       L      6
  </code></pre>
  
  <p>I need to create an adjacency matrix for usage downstream in creating a chord diagram. I am looking for an efficient way to get it.</p>
  
  <pre><code>    A   B   C  D  L
  A   0   3   4  10 6
  B   3   0   0  0  0
  C   4   0   0  0  0
  D   10  0   0  0  0
  L   6   0   0  0  0
  </code></pre>
  
  <p>I am looking for a visualization as follows</p>
  
  <p><a href="https://i.stack.imgur.com/LogAg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LogAg.png" alt="Chord Diagram"></a></p>