Radial Column Chart
Source: Data Visualisation Catalogue - Radial Column Chart
Why This Belongs In The Compiler Gallery
Radial column charts use equal angular bins and value-derived radial length. They exercise the same polar-sector compiler path as Nightingale rose charts, but with a visible inner baseline.
Data Contract
Each raw row is one ordered category value.
| Field | Type | Purpose |
|---|---|---|
month | ordinal | Column category and legend label. |
value | quantitative | Quantity encoded by radial column length. |
pathD | text, derived | Generated annular column path. |
innerRadius, outerRadius | quantitative, derived | Radial baseline and value-derived outer edge. |
labelX, labelY | quantitative, derived | Value label anchor coordinates. |
Compiler Mapping
| Compiler part | Mapping |
|---|---|
| Data source | monthly-index raw rows and derived columns. |
| Transform | layout with layoutKind: "polarSectors" and layoutMode: "equalAngleRadius". |
| Scales | color: ordinal(month). |
| Layers | Annular path columns plus value labels. |
| Guides | Generated color legend. |
Faithfulness Notes
The core radial columns are compiler-owned now. Remaining work is true polar axes/rings and a linear-radius option for examples where length, not area, should carry the value.