The goal of this session is to help participants in the training with the modules that bring the Grammar of Graphics in practice:

• Grammar of Graphics in practice: Tableau
• Grammar of Graphics in practice: Vega-Lite
• Grammar of Graphics in practice: ggplot2
• Grammar of Graphics in practice: Observable Plot

It is also meant as a support for the Assignment: making visualisations with the Grammar of Graphics module.

Please try to go through these modules before this session. If you run into any issues, or if you have questions about how to accomplish something in any of the visualisation tool, you can ask them during this session.

To allow the trainer to prepare answers to your questions, you can post your questions below.

Questions

[TYPE YOUR QUESTIONS BELOW]

[Question from Vosnier]

So far I’ve played a bit with Vega-Lite and Observable Plot and I can see the advantages of working with the Grammar of Graphs. Could you give us an overview of the pros/cons of each tool in terms of output options? For example:

• How easy is to embed the code generate by these tools on a HTML page and make these visualisations responsive and accessible? In Vegalite, I’ve got a simple HTML code to download but it get partially rendered In Observable Plot, I’ve got a package of files to download and the final output is a white page
• Which ones offer the options to download as svg file?

In Observable, can we refer to a dataset hosted in the cloud instead of adding it as an attachment, in the same way as we do in VegaLite? - e.g."data": {"url": "data/seattle-weather.csv"}

Answers

Exporting HTML from Vega-Lite

For the HTML export to work, the data needs to be specified inline (directly in the Vega-Lite specification), or the source of the data needs to allow external loading, which seems not to be the case for the data source we used in the Vega-Lite tutorial.

Embedding Vega-Lite visualisations