title: Pandas numpy compare two array of different size
body: <p>I have 2 arrays, one of 1000 values and the other one of 8448 values.
  I'm tryig to count the number of identique values in the two dataframe.</p>
  
  <pre><code>t1 = dfRight['X'].values
  t2 = dfLeft['X'].values
  t1 == t2
  </code></pre>
  
  <p>But it return "False", someone know an easy ways to do this please ?</p>