The Treemap view displays hierarchical data as a set of nested rectangles to mimic a tree diagram. Each parent branch of the tree is a rectangle which is then further divided into rectangular segments representing child branches. The area of each rectangle represents a proportion of each category or branch it represents. Parent branches are differentiated by assigning different colors to them.
The Treemap view goes up to two levels. The first level rectangles are called Parent Branches and the second level rectangles are called Child Branches.
In the "Views" tab of your visualization, click the Treemap thumbnail to configure a Treemap view for your visualization.
The configuration window will appear with the settings on the left and a preview on the right. The preview will automatically update as you make edits.
There are two tabs in the settings on the left: "Controls" and "Descriptions".
The "Controls" tab lets you configure how your data will appear in your visualization.
"Configure Menus" is where you can edit the fields users will have access to in your view. For each option selected in the drop-down menu, you will find a list of fields. Select the checkboxes to show or hide fields in the corresponding menu of your view, and click the home icon to determine the initial setting for your view. (To edit the field name, return to the fields tab in the main menu of your visualization.)
In the drop-down menu you can select these options:
- Group By: This menu determines the field to use for determining the individual Parent Branch rectangles. For example, In “Nobel Prize Laureates” visualization, each prize is associated with one of five categories (Peace, Medicine, Physics, Chemistry, Economics, and Literature). If you select category as “Group By”, there will be five Parent Branch rectangles differentiated by color. The fields you turn on for this should generally be nominal fields.
- Chart By: This menu determines the field to use for determining the Child Branch rectangles or subcategories. For example, In “Nobel Prize Laureates” visualization, if this field is “Birth Country”, and group by is “Category” then there will be as many Child Branch rectangles in each Parent Branch rectangle as the Birth Countries that fall into that a category. The fields you should turn on for this view should be a nominal subcategory to the Parent Category.
- Aggregate By: Determines what to base the area of the rectangle on. This is normally set to "Number of Items" by default, in which case Gist will sum the number of times a particular match occurs. If you have a Number field that you would prefer to aggregate by (for example population), set the default to that field.
The "Descriptions" tab finally lets you add a description and meta-description to your view. The description will appear at the top of the view and is a good way of orienting users to what they can hope to take away from the view. The meta-description lets you add a write-up of the key takeaways from your chart for screen readers.