title: Drop rows based on a threshold value of a column
body: <p>With elasticsearch search Indexed the data. The input file much match query is dob and last name. It has student with same dob. So that file also coming as output. Have an idea about to remove low score rows. How can I approach?</p>
  
  <pre><code>Filename Name      DOB         Score PageNumber
  11086   Ram     11 06 1930  6.4504585   1
  11086   Ram     11 06 1930  6.4504585   2
  11086   Ram     11 06 1930  6.4504585   1
  81564   Kiran   11 06 1930  3.5517883   2
  81564   Kiran   11 06 1930  3.5517883   33
  81564   Kiran   11 06 1930  3.5517883   12
  754133  peter   11 06 1930  2.5905614   1
  754133  peter   11 06 1930  2.5905614   1
  </code></pre>
  
  <p><strong>Desired output</strong> </p>
  
  <pre><code>Filename Name      DOB         Score PageNumber
  11086   Ram     11 06 1930  6.4504585   1
  11086   Ram     11 06 1930  6.4504585   2
  11086   Ram     11 06 1930  6.4504585   1
  </code></pre>