Whenever working with anything geographical, maps are a cool visualization. One of the new visualization types in Power BI is the filled map, in which regions may be colored rather than just pinpointed. For example:
And like regular maps, filled maps may work as filter sources as well as filter targets. In this next image, the bar chart acts as a filter on the table and the filled map:
And in the following illustration, the filled map acts as a filter on the table and the bar chart:
And now the tip. If you copy the filled map, you get one to work as a filter on the other and therefore create simultaneous high-level and low-level views of the selected area:
This of course works with a filled map filtering a regular map and vice versa.
You can expand this to another level of geographical detail, as in this image with US counties, in which the state of Tennesse is selected in the top map:
In a future post I will work through this last example step by step. It uses diverging coloring with custom minimum and maximum population values to color the top map, and ranking in DAX to display the top 10 most populated counties.
Get a sample Power BI Desktop file here.