30 Days of Maps Day 1 - Points
November 1st kicks off the 30-Day Map Challenge. Each day in November brings a new map visualisation challenge, and naturally, I'll be using Icon Map Pro in Power BI.
Throughout the month, I'll be showcasing the visual's capabilities, including both existing features and new ones we're about to release. We'd love for you to join in too—if you're interested, please get in touch at support@iconmappro.com, and we’ll send you a time-limited version of the visual for embedding on your blog—the same version I'll be using.
The theme for Day 1 is points - A map with points. Start the challenge with points. Show individual locations—anything from cities to trees or more abstract concepts. Simple, but a key part of the challenge.
Both built-in Power BI visuals can display circles or bubbles for point data, so I wanted to push the boundaries a bit and showcase something beyond what the standard visuals can do. Obviously I needed some point data, and I was keen to show something new that I haven't worked with before. I extracted the locations of every postbox in England from OpenStreetMap data. There are over 74,000 of them, which poses a challenge for Power BI, as its visuals are typically limited to 30,000 rows of data.
Icon Map Pro is capable of displaying up to 180,000 rows of data and we've been working hard on extending that in the latest releases, adding new performance improvements. In the forthcoming release it can comfortably display up to 360,000 circles (with labels and tooltips if required) and we hope to extend that further. Whilst we can now display all those points on the map at once, some might argue that it doesn't make sense to do so, which is why we're also working on improving our clustering. You still need to be able to include all the points, before you can cluster them - so even with clustering increasing the number of rows is essential.
So let me walk you through the map below.
Background map - this is our built in 'Positron' style, which is normally light grey. However, I've changed the colour of the water to white and land background to pale green using a forthcoming Icon Map Pro capability.
Overlay - I've overlaid the local authority boundaries (downloaded from geoportal.statistics.gov.uk).
Points - Using QGIS, I geocoded each postbox location with its respective local authority area, allowing the report to filter locations with a Power BI slicer. Each postbox is represented by a red circle on the map. A tooltip shows the operator, collection times, and postcode of each postbox where this information is available. I’ve added two versions of the map, switchable with bookmarks accessed via the “Cluster” button. One version shows all 74,000 circles at every zoom level; the other clusters the postboxes, displaying the number within each area.
If you'd like to see how the report was built, you can download it here.
I'm already looking forward to tomorrow's challenge - lines.