0 Replies Latest reply on Apr 29, 2013 7:34 AM by Thomas Beaulieu

    error with user defined aggregate

    Thomas Beaulieu

      I am trying to perform a simple weighted average calculation and for the life of me cannot figure out why it does not work.  Here are my data:

       

      Part Number
      Ship Quantity
      Ext Sell Price
      ABC101000
      ABC1150
      ABC8850
      ABC2290

       

      I want to sum the EXT sell price (2290) and divide by the sum of the ship quantity (21) so that Part Number ABC shows a weighted average price of 109.05 within a Tableau table.  The equation I am using is SUM([EXT Sell Price])/SUM([Ship Quantity]).  The dialog box for the calculation formula gives me a green check indicating that the calculation is valid but when I apply the equation, my calculated field name (average sell price) shows up red with the following message:

       

      "The calculation 'SUM of average sell price' can't be applied to a user defined aggregate"

       

      This makes no sense to me.  I feel like I am making a simple, rookie mistake.  Any thoughts?

       

      Tom