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Interface: Series<T> ​

Defined in: packages/core/src/series/types.ts:114

A data representation that can be swapped out on the same stage (Plot).

The grid, axes, pan/zoom, and layers belong to Plot, so they stay put even when the series changes. A series answers five things — how much of the y axis it occupies, how it draws, and (optionally) how its points are thinned, how their coordinates are read, and what a tooltip says about one of them (describe, the series' alone — no registration overrides it). The two policies are resolved registration first, then the series, then the fallback: a registration's coordinates wins over the series', and plain x/y reads when neither says; a registration's decimation fields win over the series' field by field, and the wiring's policy fills what neither sets.

Type Parameters ​

T ​

T extends BaseDataPoint = BaseDataPoint

Properties ​

barBody? ​

readonly optional barBody?: boolean

Defined in: packages/core/src/series/types.ts:166

Whether each point is drawn as a body one bar slot wide — a candle, a bar, a histogram column. A fit pads the chart by half a bar at each end when any series says so, so the end bodies are drawn whole; a chart of lines alone fits edge to edge.

coordinates? ​

readonly optional coordinates?: CoordinateAccessor<T>

Defined in: packages/core/src/series/types.ts:144

How to read coordinates from its own point. Omitted means reading x and y directly. It's here for the same reason as decimation — a candle's value is close (OHLC has no y), and only the candle knows that.

decimation? ​

readonly optional decimation?: DecimationPolicy<T>

Defined in: packages/core/src/series/types.ts:136

The decimation policy fit for this representation. Omitted means wiring decides — this is a series's third responsibility. A candle can't be thinned, only aggregated (thinning loses the interval's high and low); one per pixel is the ceiling. A registration can override this (SeriesRegistration.decimation).

Methods ​

describe()? ​

optional describe(point): readonly SeriesRow[]

Defined in: packages/core/src/series/types.ts:158

The rows a tooltip or legend shows for one of its points — a candle says O/H/L/C and, when the bar has one, V; a line says nothing here and the consumer shows its one value — leaving this out, or returning [], both mean "nothing to say". Called on every probe — a crosshair move, every tooltip and legend refresh, and the magnet crosshair's own draw, twice a frame — for every registration on the pane, so it must be cheap and pure. The point is the one held for drawing — the series' own T, after any derivation — not a pixel-aggregated candle. Values are numbers; how they read is the consumer's formatter, row by row. This is the series' answer only — a registration cannot override it.

Parameters ​

point ​

T

Returns ​

readonly SeriesRow[]

draw() ​

draw(target, context): void

Defined in: packages/core/src/series/types.ts:127

Parameters ​

target ​

DrawTarget

context ​

SeriesContext<T>

Returns ​

void

valueExtent() ​

valueExtent(data): Range | null

Defined in: packages/core/src/series/types.ts:125

The range this representation occupies on the y axis. A line is a single point, so min === max, but a candle occupies a low-to-high span — that can't be expressed as a single number, so it returns a Range.

null when there's nothing to measure — returning { min: 0, max: 0 } would let a series whose data hasn't arrived yet drag the value axis down to 0.

Parameters ​

data ​

DataView<T>

Returns ​

Range | null