Tableau - How to Use a Condition to Filter week(Date)

Question

I've got google analytics data for goal completions represented in a line graph in Tableau, with the week of the year as the x axis. What I need is to set a conditional filter on WEEK([Date]) so that all but the most recent week is shown. Something like this :

IF DATEPART('week',[Date]) < DATEPART('week',TODAY())
THEN 'Show'
ELSE 'Filter'
END

But when I try this, I get an error saying "The formula must be an aggregate calculation or refer only to this field" .

Could someone fix the formula for me?

Answer 1

Rather than trying to set this in the filter dialog box (I received the same error you experienced when trying to do it that way), use that formula to create a calculated field. Then simply drag that field to the filter box and filter on 'Show'.