#TweakThursday 34: Placing Labels on Tiled Map

Georgia Chen created a tiled map for a recent #MakeoverMonday project. She had a hard time placing the labels on the tiles. And she ended up doing it manually. Yes, you can drag and drop the labels to a place manually.

Tiled map is often used chart type, which is a kind of small multiples. In a tiled map, there is always a label in each tile to indicate the actual location or the category of the tile.

How to place the label at a desired position? The general approach is to
- create a single mark chart at a desired position.
- put the label on the mark
- dual axis with the existing chart.

Georgia already used dual axis to place a colored arrow at the end of line chart. I moved the arrow to the label using a number formatting technique. So I saved the dual axis for later use.

Position the tile label
Each tile here represents a state (or a union territory) in India. Note that the horizontal axis is year, and the vertical axis is a percentage. To place the label at the upper center, I created a measure [Mark] as follows:

• IF [Year]=2014 THEN 0.8 END

This will place the mark at year 2014 and at the height of 80%. We select white color to hide the data mark so that it is not visible. Last, place State (Group) on the Label shelf.

Aggregate the measure Avg(Mark)
The dimension State (Group) is being used instead of State because of recent state readjustment. Andhra Pradesh and Andhra Pradesh (New) are grouped together. Sum(Mark) would have produced 1.6. We need to use Avg(Mark) to keep the mark at 80%

Dual Axis and synchronize
Place Avg(Mark) at the Row shelf. Dual axis with the main measure. Sync the scale with the main axis. We get the labels in the desired place.

Voila the tweak of the week.