All credit for the original template, method, and workbook goes to the Flerlage Twins. Thanks for letting me create this!
Prep Template Build Video: Coxcomb Chart Tableau Prep Template: Put Some Prep in Your Step - YouTube
I recently shared that I'm revisiting some of the popular Tableau Templates from the Flerlage Twins and creating Tableau Prep templates for them. If you haven't checked out the Sigmoid Bump Chart template, you can see that here: Curvy Bump Chart & Slope Chart - Tableau Prep Template (whattheviz.com)
The next template on the list is one that was posted more recently and that I've seen popping up more and more: The Coxcomb Chart! I used a version of this in My Iron Viz submission as well, with a few tweaks to get the shape I was really looking for.
One thing I will say again, I'm not inventing anything new here. Kevin and Ken are the real pioneers of this work, I'm simply providing a way to incorporate Tableau Prep if you use their templates. For a brief history of the chart, how to build, and use cases, check out their original blog post here (you'll also find the link to the workbook there): Tableau Coxcomb Chart Template - The Flerlage Twins: Analytics, Data Visualization, and Tableau Another note with these templates is that they're not necessarily a better or even quicker way of building these charts. The focus here is to help you understand what is happening behind the scenes. To build out-of-the-box charts in Tableau, there is often a lot of data preparation and restructuring that needs to occur. With Tableau Prep, you get to see step by step how the data is being processed. These templates will also provide a way to modify your data viz process in general. Instead of jumping right into workbooks, processing the data first and profiling it is a good practice to have. So with that, let's jump in!
We're going to start with the same Data sheet mentioned in the original blog post (Coxcomb Chart Template - Google Drive)
The Data Below is what you should see when you open the Excel Workbook.
You'll want to reference Ken & Kevin's original post to understand how this needs to be filled out (Tableau Coxcomb Chart Template - The Flerlage Twins: Analytics, Data Visualization, and Tableau) Note: Apologies if some of these links are repetitive. I want to make sure these posts are as easy to move through as possible. If the link only needs to appear once at the top or bottom of the page, let me know. Feedback will help me improve the overall structure and make these posts as useful to you as possible.
Once you've got your Data sheet filled out, you'll want to download the Prep flow from the google drive. When you open it up, you'll have some errors:
We're going to use the excel sheet as an input and add it to those steps to correct the errors.
In the Connections pane in Tableau Prep, click the plus sign and then Microsoft Excel
Connect to the filled out excel sheet. Since it's only one sheet, it should be automatically pulled onto the canvas. If not, just drag and drop the Data table to the area.
Next, you'll want to click and drag the Data Input and hover over the step called Scaffold Range. You'll see three options, one of which is 'Add'. You'll drop the step on that option.
You'll do the same with the Join step.
You should end up with something like this where the Data input is connected to both the Scaffold Range and the Join steps:
From here, you just click on the play button next to the output step, designate a destination for the file, and you're ready to connect to the bump chart workbook! (Coxcomb Chart Template | Tableau Public)
When you open the workbook, you'll find Data in the toolbar and click New Data Source
In the connection menu, you'll go to "More..."
Now, you'll go to the Curvy Bump Chart Sheet and replace the data source with the new one.
All of the calculations from the original data source will be pulled in, and your Coxcomb chart is looking ready to start building around!
I hope you are able to make use of this Prep template! If you'd like to learn how it was built, check out the video here: Coxcomb Chart Tableau Prep Template: Put Some Prep in Your Step - YouTube