Tableau 9.0 introduced a new way of creating and using calculations. Ad hoc calculations add calculated fields to shelves in a single view without adding fields to the Data window.
Let's say you have a simple view that shows the price per renter, like this:
What if you wanted to quickly highlight any renters who had a contract of more than $3,000? One option would be to create an ad hoc calculation. To do so, simply double-click on an empty area of the Columns, Rows, or Measure Values cards or on the empty space of the Marks shelf and then start typing the code for a calculation. In this example, we've double-clicked on the empty space on the Marks shelf:
Here, we've entered code that will return True if the sum of Price is greater than $3,000 and False otherwise. Pressing Enter or clicking outside the textbox will reveal a new ad hoc field that can be dragged and dropped anywhere within the view. Here, we've added it to the Color shelf:
