For this tutorial, I am going to show you how I have done the Radial / Circular Bar Chart for my #GamesNightViz submission around a year back. I have not seen this method being used extensively, but there are some caveats. First, you will need to set up the data in Excel. Next, it may be tedious as you the chart layer by layer. Lastly, the chart size is hard to control as it is created using mark layers. I have also realised I cannot do small multiples using the popular "calculated fields" method.
Nonetheless, the final product as pictured above looks like the effort is worth it.
Step 1: Set up the Data
- Go to Excel or any way you use to set up your data.
- Below is the explanation for the setup for the columns:
- Column A is for the character (or any item).
- Column B is the category of the slices.
- Column C is the value that will determine whether they will be coloured (Y/N in the below bullet point)
- Columns D to H are for the colour. If it is "Y", the part of the slice will be coloured. If "N", it will be the same colour as the background.
- Columns I to M are the angle. As the chart is created using a pie chart with 5 slices, each slice is 20 so we get 5 equal portions.
- Column N is a random location to activate the map layers.
Step 2: Set Up the First Layer
- Drag and drop as pictured below.
- Drag the auto-generated "Longitude" and "Latitude" to "Column" and "Row" respectively.
- "Location" into "Details"
- "Character" in "Shapes" after setting the "Mark Type" to "Shapes". This is for the centrepiece of the chart.
- Edit the "Map Layers". Click "Map" on the top. Then click "Map Layer". Turn the "Washout" to 100% for a blank canvas.
Step 3: Create the Marks Layer
- Create 6 more layers by dragging "Location" into the map to activate the "Marks Layer".
- 1 for the blank centre and 5 for the scoring in this dataset
- To work conveniently, you can place the item you will be breakdown into the filter. In the case of the example, it is "Character". Then filter to 1 thing.
Step 4: Set up the Next Layers
- Make 2nd layer a circle and the same colour as the background.
- Make the next few layers of pie charts by dragging in and arranging the necessary pills as follows:
- Refer to Step 1 for details of each layer.
- Change "1" and "One" corresponding to the layer.
- Change each layer's size so they will not cover the other.
- This has to be done layer by layer similar to the above steps.
- Add in the "Text" for the last layer.
- In my case, I have used "Stat" and "Value"
Step 6: Publish Your Polar Area Diagram!
