COVID-19 has started to spread around the world and the situation is becoming more and more serious. We are paying close attention not only to the development of the epidemic at home, but also the development of the epidemic abroad. Through geographic visualization, we can intuitively see the severity of the epidemic in each region. In this paper, the world epidemic map as an example to describe the differences between different types of visualization, but also provides a fill map, 3D fill map, bubble map, 3D histogram, bubble dynamic map source code, data for real-time data interface data. You can customize and develop your own epidemic map. Online Demo GitHub address welcome star.
At present, we commonly use the epidemic map in the form of fill map to express the differences of different regions through color differences. Let’s take a look at the epidemic map of each platform.
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| Baidu version | Clove garden version | Today’s headlines |
Choropleth Maps
- The fill diagram is suitable for expressing differences between regions.
- The filling diagram can well show the global differences of shapes, and subtle differences are difficult to express.
In the infill chart above, we can focus on Asia, Europe and the Americas, but we can hardly focus on the severity of the epidemic in Italy and South Korea.
- The display effect of the filling diagram is greatly affected by the area, which is easy to mislead
The severity of the epidemic in the United States is relatively less serious, but the visualization form of the filling map is more likely to attract attention due to its large territory, while South Korea, Italy and France are less likely to attract attention due to their small size. How to avoid the misleading caused by the visualization of filling graph, we introduce another visualization form bubble graph here.
Bubble chart
Bubble plots use circles of different sizes to represent values over the region. It displays one bubble per geographic coordinates, or one bubble per region.
In the following figure, we visualized the epidemic map in the form of bubble chart
Through the bubble map, we can clearly identify the countries with serious epidemics in the world without being affected by regional area. We can also clearly identify some countries with relatively small areas in Europe. The shortcoming of bubble graph expression is that too many bubbles, too large will produce cover now. Bubble is a good form of presentation, but it will also cause interference if improperly used, such as data mapping method selection and color ribbon selection will affect the results of data expression.
Enhanced pandemic map
With the emergence of new technologies, the ways of data expression are becoming more and more diversified. On the basis of the fill map and bubble map, an enhanced version of visual expression has appeared. We have developed an enhanced version of epidemic map with the visual ability of L7.
3 d fill the figure
3 d histogram
Dynamic bubble diagram
Maps are not objective, they are just a manifestation of reality, depending on what we use the map to express, how to express.
How to develop epidemic maps
The map visualization engine uses Ant Financial’s open source visualization engine L7. You can visit the official website of L7 for documentation and examples on how to use it. (just about. Antv. Vision/useful/examples…). , provides complete demo and code examples, data for real-time epidemic interface data, you open to see the latest epidemic distribution map.
This tutorial
If this article is useful to you. Don’t forget to go to GitHub github.com/antvis/L7 and light up the little star.