Histogram

A frequency-distribution chart: bins continuous values into equal-width buckets and renders the counts as a BarChart. Useful for benchmark distributions, latency percentiles, request-size histograms.

See also: BarChart for values you already have per category.

Import: package:fleury/fleury.dart, or package:fleury/fleury_core.dart in browser code.

Usage

// Pass raw samples; the chart buckets them into equal-width bins.
Histogram(values: latenciesMs, bins: 7, showValues: true)

Details

Range defaults to autoscaled [min(values), max(values)]. Bin labels are the midpoint of each bucket; when they would collide, only an evenly spaced subset is shown, and showLabels: false turns them off.

Screen readers and agents get one chart node: semanticLabel plus the bin count, how many values fell in the range, and the range’s low and high ends, not a node per bin.

Constructors

`Histogram()`

Parameter	Type	Default	Description
`values:`	`List<num>`	required	Raw observations to bin.
`bins:`	`int`	`10`	Number of equal-width bins (≥ 1).
`range:`	`(num, num)?`	—	Explicit `(low, high)` range. `null` autoscales to `[min, max]` of `values`. Values outside the range are dropped.
`showLabels:`	`bool`	`true`	Whether bars show their bin midpoint labels. When labels would collide, only an evenly spaced subset is shown.
`showValues:`	`bool`	`false`	Whether each bar shows its observation count.
`barWidth:`	`int`	`2`	Width of each bar in terminal cells.
`gap:`	`int`	`0`	Horizontal gap between adjacent bars in terminal cells.
`color:`	`Color?`	—	Bar color override; defaults to the theme’s primary.
`semanticLabel:`	`String`	`'Histogram'`	Label exposed through the semantic app graph.

Source

Histogram is defined in packages/fleury/lib/src/catalog/histogram.dart.

Category: Charts & meters · All widgets