2 Replies Latest reply on Mar 10, 2015 1:04 PM by Xiaoyang Yang

    Have a problem of Lookup() funciton

    Xiaoyang Yang

      Hello,

       

      I just start to learn Tableau and I brought a book, in this **** there  is a example, the dataset is like:

      Screen Shot 2015-03-09 at 11.06.04 PM.png

      So we have to compare each team's performance for different year; like for Arsenal, we want to know the difference of its Win games(W) in 2013 to 2012, so it should be 11-5=6, but the writer use a function `LOOKUP(SUM(W), LAST())-LOOKUP(SUM(W),FIRST()) to calculate the difference for each team, i really cannot understand, can anyone express it to me;

      I know the lookup() function, but I cannot understand this expression.

      Thanks~~