How to define shapes within your mapping visualizations.
At Qonnections, I noticed that there was a great deal of interest in mapping while talking to people at the Analytics8 booth and presenting one of the technical breakout sessions.
With a lot of first time mapping users asking questions, it reminded me that if you’ve never done anything with maps, the topic can be a bit overwhelming at first.
I remember the first time I saw a map I was puzzled by how the shapes on the map were made. We’ve come to accept that the visualizations at our disposal come pre-installed with our Qlik Installation. I don’t have to build squares for bar charts or circles for a pie chart; the Qlik Engine takes the numbers I give it and displays them in a square or circle format.
Not so with a map.
Each shape (state or province) has to be defined in the data model before it can be formatted (color or opacity) using an expression. Defining shapes that go on a map takes a mental leap that most never make until you start working with a map.
Shapes can be stored in a number of different formats, similar to how data can be stored in SQL or a .QVD. Each format has its advantages and disadvantages and therefore each method of displaying shapes on a map in a Qlik Environment differ slightly depending on the need.
In Sense, native mapping uses .KML files. KML files (Keyhole Markup Language) can be found through a number of pay providers or on the web. Please be careful though when downloading KML files on the web. Not all shapes are created equal and the cost to license the use of certain KML files can be expensive.
QlikMaps uses a compressed format that fits nicely in Qlik’s In-Memory environment and is stored in a standard .QVD file format, allowing optimized loads of large territories. These files cannot easily be found by searching the web but can be downloaded from the QlikMaps download page.
Suffice to say, when looking at adding a map, some thought has to go in to what you need to show on the map and where you are going to get the shape files from. It’s no longer possible to just take for granted that Qlik is giving you everything you need to build a visualization. Spend some time doing some research on the different formats and technologies out there and invite someone with a bit of expertise on mapping to help get you started. It’s not hard, but it is a different thought process that requires a bit of planning.
For those of you reading this that were at the QlikMaps technical breakout session, thanks for coming! Here's the Maps That Matter webinar I mentioned in the session.
This article originally appeared on the Unconventional QlikView blog.