5 Replies Latest reply on Aug 3, 2018 3:58 PM by Shinichiro Murakami

    Create .25-mile radius circle around lat/long points on map

    Leigh Michael

      Hi all,


      I'm hoping to get some advice on how to create circles that cover a .25-mile radius around a lat/long point (which represents a bus stop) on my existing Tableau map. Basically, my goal is to see which census blocks each bus stop serves. For some context:


      I have three files:

      1. A shapefiles map of King County, divided by Census block.
      2. An excel sheet that gives me the median household income of each census block.
      3. An excel sheet that has the lat/long coordinates of certain bus stops in King County.


      Files 1, 2, and 3 all have one "like" field: the Census block ID, which I have used to join the data. I need my dual axis map to do the following:

      1. Display a King County map divided up by Census block [DONE!]
      2. Be able to hover over each Census block on the map to see the median income of that block [DONE!]
      3. Be able to see each bus stop on the map as a dot [DONE!]
      4. Be able to hover over the bus stop point to see the bus stop's line ID [DONE!]
      5. Customize the color of the bus stop point so it stands out on the map [DONE!]
      6. Have a .25-mile radius around each bus stop point, so I can see which census blocks it covers. [NOT done]
        I would like to be able to customize the color/transparency of the circles. Ideally, I would also like the circles to only show up when I hover over the bus stop point so the map isn't too crowded.


      As you'll see in the packaged workbook, I've achieved steps #1-5. But I'm struggling with #6. I looked at this thread but haven't been able to crack how to do it yet - I don't have any experience with SQL, so it's new territory for me.


      My packaged workbook is attached below, and I'm using Tableau 10.4 Desktop.


      I would be so grateful for any advice on how to do this. Thanks!