7 Replies Latest reply on Dec 21, 2016 4:01 AM by Simon Runc

    Dual axis symbol and filled map, using different lat/long

    Cambria Brown

      I would like to make a layered/dual axis map of the following:

      1. A symbol map based on the latitude/longitude in my dataset showing the physical locations of offices

      2. A filled map colored and labeled by "region"

       

      The problem is when I make the filled map with the labels I want using the generated lat/long (as I've done in the 1st tab in attached), I am not able to add the marks I want using the non-generated lat/long.  And when I make the marks I want with the non-generated lat/long (as I've done in the 2nd tab), I am not able to label the map the way I'd like to, because it wants to label each mark instead of each region.  I really appreciate any help!

       

      Thank you,

      Cambria

        • 1. Re: Dual axis symbol and filled map, using different lat/long
          Simon Runc

          hi Cambria,

           

          So to get a dual axis map you do need to only use one set of Long/Lats...if you are interested in how to "hack" area and points together, the basic idea is in my TTD Think Data Thursday: My Daily AdVIZture - August 25, 2016 (although these are plotting routes and points the basic idea is the same, a route is just an un-joined polygon!!). It really comes down to doing a horrible union of polygon and point data

           

          However, in your example, I can see you have zip codes for your institutions (points)...as these also use the generated Long/Lat we are able to get both Region (area) and Institutions (points) on the same map by changing the Geographic detail (on has Region in Detail, and other uses ZipCode) and changing the mark type (area map for region and squares/circles for institutions) for the 2 layers.

           

          Hope that helps

          • 2. Re: Dual axis symbol and filled map, using different lat/long
            Cambria Brown

            Hi Simon,

             

            Thank you so much for this reply.  I do have zip codes in my data source and your second suggestion is how I originally made the map.  However, there are multiple rows with the same zip code so when I make the map that way, I end up with up to 5 points overlapping in some cases when I need each point to display separately.  I will check out your blog post and see if I can get that solution to work - it sounds complicated!

             

            I really appreciate your help!!
            Cambria

            • 3. Re: Dual axis symbol and filled map, using different lat/long
              Simon Runc

              Glad it helped...so even if you have multiple rows for the same institution you can "control" how many marks are plotted by using the detail tile.

               

              By only bringing in Zip Code and then using "LPHA (LPHA address and phone number)" brought in as an ATTR (attribute) it doesn't increase the vizLoD beyond Zipcode.

               

              So if I just look at the points (with ZipCode as a dimension, and LPHA (LPHA address and phone number) as an attribute) I have 92 marks

               

              Although it appears (adding Address Type as an ATTR to the colour shelf) there are multiple assignments for some Zipcode...which is why we get the * in the legend)

               

              If I dis-aggregate the data (Analysis Menu and un-tick aggregate measures)...we now have 176 marks (as this is plotting a mark for every row)

               

               

              So you don't have to plot a mark for every row, if you aggregate the viz to the desired level.

               

              Hopefully, that makes sense?

              • 4. Re: Dual axis symbol and filled map, using different lat/long
                Cambria Brown

                Thank you again for your help.  However, I am still not quite getting the desired effect.  When I plot the locations by zip code and follow your instructions, all of the "physical address" locations disappear when the data is disaggregated, and still not all of the locations appear on the map.  For example, when I use zip code for the locations (even when following the steps you outlined), there are only 2 distinct points in Denver county and when I use the lat/long from my dataset there are 5 distinct points in Denver county (which is what I want).

                 

                using zip code.PNG

                 

                using lat-long.PNG

                • 5. Re: Dual axis symbol and filled map, using different lat/long
                  Simon Runc

                  hi Cambria,

                   

                  So looking at the data in Denver...I have 2 distinct zip codes

                   

                   

                  Zip code
                  80204
                  80223

                   

                   

                  but 4 distinct LongLat

                   

                  LatitudeLongitude
                  39.72601-104.991
                  39.72689-104.99
                  39.71557-105.003
                  39.73845-104.99

                   

                   

                  So you'll need to have 4 distinct ZipCodes if you want to use the "Generated" long-lat.

                   

                  So disaggregated you'd get 12 marks (the number of Denver Rows)...although (depending if you are using generated long/lat or your long/lat you'll get the point plotted over one another, so would only see 2 or 4 respectively)

                   

                  So you'll need a (distinct) zip-code per location you want plotted, or if you want to use your-long/lat you'll need to create the regions as from a shapefile...which will be a lot of work ...here's my wiki article on one way to do this...Step By Step Instructions – ShapeFile to Custom Polygons using Open Source GIS (QGIS)

                  • 6. Re: Dual axis symbol and filled map, using different lat/long
                    Cambria Brown

                    Yes, that is exactly the issue!  And that is why I want to use my non-generated lat/long for the points and the generated region-level lat/long for the fill.  Sounds like there's no "easy" way to do this.  But I am actually in the process of making "dummy" zip codes in cases where they repeat right now to use for the points, since the exact location isn't really that important.

                     

                    Thank you again for your help - it is much appreciated!

                    • 7. Re: Dual axis symbol and filled map, using different lat/long
                      Simon Runc

                      Cool...just because I like playing with Tableau!! I have created you a version using your Long/Lat. As we can only use 1 set of Long/Lats, this means I've had to manually create the areas from a Shapefile (btw I have Tableau 10.2 Beta and we can now import shapefiles directly...thank Zeus!!). I've also attached the Excel I used to create it. One tab is the Institution names with their Long/Lat (your fields) and the other is the shapefile made into Tableau format (using the link I sent...well actually I used Alteryx for speed but it does the same thing). I then Union these 2 tabs together and use a couple of tricks from my Daily Advizture webinar...and voila we can use your Long/Lat. I've then blended in some fields from the original data source to colour the map...etc.

                       

                      I don't advise this...but just to show it can be done (and how)