Vertical Stack Bar API

Show what each category is built from, segment by segment, with missing parts flagged instead of dropped - see the Vertical Stack Bar demo.

Import

Web Component

import "@michi-vz/wc/vertical-stack-bar-chart";
// <michi-vz-vertical-stack-bar-chart> is now defined

Vanilla JS

import { mountVerticalStackBarChart } from "@michi-vz/core";

const chart = mountVerticalStackBarChart(el, props);

Props

Prop	Type	Default	Description
dataSet*	VerticalStackBarDataSet[]	—	Array of grouped series; each entry contributes its own bar slot per date and stacks its segment keys vertically
keys	string[]	—	Explicit stack order; present keys first (in this order), natural keys appended.
keysOrder	"topToBottom" | "bottomToTop"	"topToBottom"	Where keys[0] sits in the stack: "topToBottom" (default) puts keys[0] at the top, "bottomToTop" anchors keys[0] at the bottom
title	string	—	Optional chart title rendered above the plot
xAxisFormat	(d: number | string) => string	—	Formats an x tick value into its display label
yAxisFormat	(d: number | string) => string	—	Formats a y tick value into its display label
xAxisDomain	string[]	—	Explicit ordered list of date band categories; overrides the auto-collected, sorted set of dates from the data
yAxisDomain	[number, number]	—	Fix the y-axis range as [min, max] instead of deriving it from the data
minBarWidth	number	5	Minimum width in px for each bar slot, floored when bands get narrow (default 5)
minBarHeight	number	15	Minimum height in px for a non-zero segment so thin values stay visible (default 15)
minBarHeightZero	number	0	Height in px drawn for an explicit zero-value segment (default 0, i.e. nothing)
missingDataMarker	{ height: number }	—	Opt-in thin stub on the zero line for explicitly-missing (null/NaN) owned keys.
filter	{ limit: number; sortingDir: "asc" | "desc"; date?: string }	—	Keep only the top-N dates ranked by grand total across all series and keys: limit caps the count, sortingDir picks highest (desc) or lowest (asc), optional date is the reference date; chronological order is preserved in output
tooltipFormatter	(rect: StackRectData) => string	—	Returns custom tooltip HTML for a hovered datum (sanitized before it is inserted)
onHighlightItem	(labels: string[]) => void	—	Called when the hovered/highlighted label(s) change
onLegendDataChange	(legendData: StackLegendItem[]) => void	—	Called with the computed legend items (label, color, order, disabled, dataLabelSafe) whenever the legend changes

Common props — shared by every chart (14)

Prop	Type	Default	Description
width	number	900	Chart width in pixels
height	number	480	Chart height in pixels
margin	Margin	{ top: 50, right: 50, bottom: 100, left: 60 }	Inner margins (top/right/bottom/left, in px) reserved for axes, titles, and labels
colors	string[]	—	Categorical palette for series/labels without an explicit colour or colorsMapping entry
colorsMapping	Record<string, string>	—	Explicit label -> colour map; takes precedence over the palette and per-item colours
highlightItems	string[]	—	Labels to emphasise; all other marks dim
disabledItems	string[]	—	Labels to hide and exclude from scales/stacks
renderer	"svg" | "canvas"	"svg"	Render as inline SVG (default) or to a canvas (faster for large datasets); getContext() is identical either way
locale	string	—	BCP-47 locale used for number and date formatting
skipColorMappingDispatch	boolean	false	External-CSS mode: unmapped labels resolve to transparent and onColorMappingGenerated is not emitted, so mark colours come from your CSS via the data-label-safe contract
enableTransitions	boolean	true	Animate updates with CSS transitions (default true)
onColorMappingGenerated	(mapping: Record<string, string>) => void	—	Called with the resolved label -> colour map after the chart assigns colours
onChartDataProcessed	(context: ChartContext) => void	—	Called with the renderer-agnostic ChartContext whenever the data is (re)processed
onDataWarning	(warnings: DataWarning[]) => void	—	Called with any non-fatal data warnings (duplicate labels, non-finite values, gaps, ...)

Events

The web component dispatches these bubbling CustomEvents (the engine exposes the same via the on* callbacks in the table above):

Event	Detail	Fires when
michi-vz:highlight	string[]	hover highlight changes
michi-vz:colormapping	Record<string, string>	a color mapping is generated
michi-vz:dataprocessed	ChartContext	data is (re)processed
michi-vz:datawarning	DataWarning[]	input warnings are detected

getContext()

mountVerticalStackBarChart(el, props).getContext() returns a renderer-agnostic VerticalStackBarChartContext (structured stats + a deterministic natural-language summary + an a11y table). See LLM context.

Source

Props are typed as VerticalStackBarChartProps in @michi-vz/core.