1. Doing more with maps - custom backgrounds
Welcome back. Let's explore another type of map visualization, but this time we will use custom backgrounds instead of geographical maps. Let's go ahead and jump right into it.
2. Spatial visualization - not only geographical maps
Often it's easier to look at a simplification or a symbolic representation of reality. Think about a metro map - it is much easier to plan your journey when looking at an abstraction of the real map rather than a detailed version.
In other cases, we might want to visualize a process, for example, how our products move along the plant production lines, to spot where the production fails or slows down.
Visualization of an in-home electricity plan or point-to-point mapping of our latest road trip using a custom map as a background is yet another use case.
3. Latitude, longitude, X, Y = coordinates
How do we get started? As every map needs a set of coordinates, in the case of geographical maps, these are latitudes and longitudes; our custom maps also require a system to describe the positioning of the objects.
Any 2D image can be seen as a set of indefinite number of points, all of which can be described by their X and Y values.
So, to determine the position of various points of interest in our custom background, we will need to know their X and Y coordinates.
4. Point and polygons custom maps
As we have already learned, polygons are the preferred geometry when visually representing an area and are a good choice when we cannot (or do not want to) specifically pinpoint an exact place within an area.
However, storing polygonal information typically requires more space and data than is the case of point maps. Therefore, point maps can be used both in case of very detailed pinpointing of specific places and are also used symbolically to represent a designated area, such as a room in a building as visible in the example on the slide.
5. Point and polygons custom maps
Both polygon and point maps can be further enriched with extra information, providing more insight on specific data points or drawing attention to, for example, production line failures or unoccupied spaces.
6. Steps in visualizing custom map data
To successfully visualize data for a custom map, we need to take several steps.
First, we will upload the background picture.
Next, we need to identify the coordinates of specific points or polygons on the image. Unlike geographic maps, Tableau will not assist us with identifying the points of interest on the custom background, and we will have to provide their X and Y coordinates. Noting them down, we create a location dataset.
If we wish to enrich the image with extra information about our custom map, we can combine the coordinates dataset with additional datasets. For example, connecting rooms with information about their occupants, their habits, hourly status on electricity usage, etc.
Lastly, we visualize the combined data by applying attractive visualizations and in some cases also animations.
7. Museum visits visualized
Before we jump into action, let’s take a quick look at the dataset we'll use in the exercises. We will work with a museum plan; we will visualize the traffic in its various areas and see how it changes throughout the day. Finally, we will investigate the typical paths most visitors take when in the museum.
8. Let's practice!
Time for a knowledge check!