How Can I Create Layered and Multi-view Plots in Vega-Lite?
Have you ever needed to create dashboards or complex visualizations that go beyond a single chart? With Vega-Lite, it's not only possible but also super intuitive! You can facet, layer, concatenate, and repeat views to achieve rich and informative data displays.
Why Should I Use Layered and Multi-view Plots?
Imagine you're a data analyst who needs to present a comprehensive view of sales performance. Single charts can only tell part of the story. By layering or placing multiple visualizations side-by-side, you can provide deeper insights and a more compelling narrative.
What's Inside?
We'll cover the following:
Faceting: Splitting Data into Smaller Plots
Faceting allows you to partition your data and create a view for each subset. Think of it as making mini-plots for each category in your data set.
Example: Creating a Trellis Plot
Let's say you want to create a trellis plot that displays sales data by region. With the facet operator, this becomes straightforward.
{
"data": {...},
"mark": "point",
"encode": {...},
"facet": {
"row": {"field": "region", "type": "nominal"}
}
}Learn more about faceting on the facet page.
Layering: Stacking Visualizations on Top of Each Other
Layering is all about placing multiple views one on top of the other. It's particularly useful for adding annotations or combining different mark types.
Example: Adding Annotations
You can layer a bar chart with a line plot to show sales trends and highlight key points.
{
"layer": [
{
"mark": "bar",
"encoding": {...}
},
{
"mark": "line",
"encoding": {...}
}
]
}Learn more about layering on the layering page.
Concatenation: Side-by-Side Views
When you want to place views side-by-side, Vega-Lite offers horizontal (hconcat) and vertical (vconcat) concatenation.
Example: Horizontal Concatenation
Place a bar chart and a line chart next to each other:
{
"hconcat": [
{
"mark": "bar",
"encoding": {...}
},
{
"mark": "line",
"encoding": {...}
}
]
}Learn more about concatenation on the concatenation page.
Repeating: Iterating Over Fields
Often, you'll need to create similar views but with different fields. The repeat operator handles this elegantly.
Example: Repeating with Different Fields
{
"repeat": {"column": ["field1", "field2", "field3"]},
"spec": {
"mark": "point",
"encoding": {...}
}
}Learn more about repeating on the repeat page.
Resolution: Customizing Scales, Axes, and Legends
Vega-Lite intelligently decides if scale domains should be unioned. However, you can customize this behavior using the resolve property.
Learn more about resolution on the resolution page.
FAQ
1. Can I mix different types of plots in one visualization?
Yes, you can mix different types of plots using the layer operator to stack them on top of each other or the concat operator to place them side-by-side.
2. How do I decide between faceting and repeating?
Use faceting when you need to partition your data into subsets (like different categories). Use repeating when you want to create similar plots but with different fields.
3. What should I do if my scales or axes don't align as expected?
You can customize the behavior using the resolve property to ensure scales, axes, and legends are handled the way you want.
So there you have it! Dive into Vega-Lite's robust capabilities to create layered and multi-view plots, making your data visualization tasks easier and more impactful.