Learn Python by Building Data Science Applications

Debugging Altair

The preceding example works, but in the real world, any development is a process of trial and error. Debugging might be daunting with the Vega stack due to the layered nature of the product (Altair converts charts into Vega-Lite, Vega-Lite converts them into Vega, and the Vega engine works in JavaScript) and because we're working in this non-Pythonic world.

As with all code in general, the process is to isolate different parts and layers of the application to identify the root of the problem. Identification will give you ideas on how to solve the problem and work around it. Unfortunately, we can't just split parts of the specification. So, what can we do if your chart does not work as intended?

Despite all of the issues, ...