title: SUM with specific condition in crystal report
body: <p>Basicalyy i want to sum data by certain condition.These are example of my data :</p>
  
  <p><code>Group 1 - Value:
      10,
      20,
      30,
  Group 2-Value:
      10,
      20,
      30,
  Group 3-Value:
      10,
      20,
      30,
  </code></p>
  
  <p>I want to sum group 1 and group 3 only.How can do it,like in sql we can write <code>select sum(group) from table1 where group &lt;&gt;'Group 2'</code>.How can we do that using formula.Or there's other way to do it.</p>