title: Intersection of two numpy arrays of different dimensions by column
body: <p>I have two different numpy arrays given. First one is two-dimensional array which looks like (first ten points):</p>
  
  <pre><code>[[  0.           0.        ]
   [ 12.54901961  18.03921569]
   [ 13.7254902   17.64705882]
   [ 14.11764706  17.25490196]
   [ 14.90196078  17.25490196]
   [ 14.50980392  17.64705882]
   [ 14.11764706  17.64705882]
   [ 14.50980392  17.25490196]
   [ 17.64705882  18.03921569]
   [ 21.17647059  34.11764706]]
  </code></pre>
  
  <p>the second array is just one-dimensional which looks like (first ten points):</p>
  
  <pre><code>[ 18.03921569  17.64705882  17.25490196  17.25490196  17.64705882
    17.64705882  17.25490196  17.64705882  21.17647059  22.35294118]
  </code></pre>
  
  <p>Values from the second (one-dimension) array could occur in first (two-dimension) one in the first column. F.e. <strong>17.64705882</strong></p>
  
  <p>I want to get an array from the two-dimension one where values of the first column match values in the second (one-dimension) array. How to do that?</p>