title: Error calling a procedure with tables owned by different breeds
body: <p>I would like to multiply the values of two different agent breeds with a function</p>
  
  <pre><code>to-report prod-val-tables [ inter popular ]
    let ans 0
    foreach (table:keys inter) [ [?] -&gt; 
      set ans (ans + (table:get inter ?) * (table:get popular ?)) ]
    report ans
  end
  </code></pre>
  
  <p>but when I call this function </p>
  
  <pre><code>prod-val-tables we-interest popularity 
  </code></pre>
  
  <p>it gives me an error because <code>we-interest</code>and <code>popularity</code> are from different breeds.</p>
  
  <p>How could I solve it? Thank you very much for your help.</p>