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YAC

The UDI grammar

The Universal Discovery Interface is a research project that aims to improve biomedical data portal interfaces. An essential component is its visualization grammar, a JSON format that can describe many different visualizations. Every chart in YAC is a grammar spec, rendered by the udi-toolkit component.

The grammar uses principles from The Grammar of Graphics, which also underlies libraries like Vega-Lite and ggplot2. A spec has three sections:

  • source defines the tabular data sources.
  • transformation (optional) reshapes the source data: grouping, aggregating, joining, deriving and filtering.
  • representation maps fields of the transformed data to visual encodings, as chart marks or table rows.

A grammar spec’s source, transformation and representation sections, and the chart they produce.

TutorialBuild a heatmap of HuBMAP datasets step by step.
ExamplesTables, bar charts, scatterplots, heatmaps and distributions.
HuBMAP examplesCharts of live metadata from the HuBMAP Data Portal.
EditorWrite a spec and see the chart as you type.

The full reference for every field is in the grammar toolkit docs.