title: Creating a new column in JMP using an if condition from another column
body: <p>I am very new in JMP so I am still feeling around. 
  I want to create a new column called "Status" in JMP. This status is character and depends on the value of the column "Grade". If the value of the entry in column "Grade" is zero, the value of the entry in column "Status" should be "fail". If the "Grade" value is greater than 100, the entry in column "Status" should be "invalid". If the :Grade" value is less than 0, the "Status" value should be "invalid".  This should be simple. But somehow, my script won't work:</p>
  
  <pre><code>dt = Current Data Table();
  dt &lt;&lt; New Column("Status", Character, Formula(
      If(:Name( "Grade" )==0, "fail",
         :Name( "Grade" )&gt;100, "invalid",
         :Name( "Grade" )&lt;0, "invalid")
  ));
  </code></pre>
  
  <p>Can you help me debug this script?</p>