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D3plus

ParallelCoordinates

Creates a parallel coordinates chart from an array of data: one axis per dimension and one line per row, crossing each axis at the row’s value. Brush along an axis to filter the lines; double-click it to clear the brush.

Basic example

Section titled “Basic example”

Each row is a line crossing one axis per dimension. With no dimensions set, every numeric key except the groupBy keys gets an axis; lines take the groupBy color. Hover a line to follow it, or drag along any axis to brush.

The lines' stroke opacity: a number, or "auto" (the default) to fade the lines as their number grows, so dense data reads as density.

curve

"linear" draws straight segments between axes; "bump" curves into and out of each axis.

Categorical axes

Section titled “Categorical axes”

A key holding text gets a categorical axis, and scale: "point" turns a numeric key into one. dimensionConfig sets each axis’s title, domain, reverse, and any Axis option such as tickFormat; curve("bump") eases each line into and out of every axis.

curve

"linear" draws straight segments between axes; "bump" curves into and out of each axis.

Brushing

Section titled “Brushing”

Drag along an axis to brush it: lines outside the brush gray out, and every brush must match (AND). To clear a brush, click its axis outside the selection, double-click the axis, or press Escape while the brushed axis has keyboard focus; clearing the last one restores every line. brushes sets them from code and holds the current selection; on("brush", fn) reports each change.

Whether each axis can be brushed to filter the lines. Drag along an axis to brush it. To clear a brush, click its axis outside the selection, double-click the axis, or press Escape while the brushed axis has keyboard focus.

Vertical orient

Section titled “Vertical orient”

orient("vertical") stacks the axes top to bottom, with each dimension’s title to its left.

orient

"horizontal" (default) lays the axes out left to right; "vertical" stacks them top to bottom.

Dense data

Section titled “Dense data”

With many rows the default lineOpacity("auto") fades every line so overlaps read as density. The Canvas renderer keeps 1000 lines smooth to hover and brush.

The lines' stroke opacity: a number, or "auto" (the default) to fade the lines as their number grows, so dense data reads as density.

renderer

Selects which @d3plus/render backend paints the visible output. "svg" = SvgRenderer (default), "canvas" = CanvasRenderer. Boolean arguments both normalize to "svg".

Above this many lines, hovering stops dimming the others and redraws skip their transitions. Raised from the usual 100, since following one line through a dense chart is what hovering is for.

Small multiples

Section titled “Small multiples”

facet draws a panel per value. Panels share each axis’s domain, and brushing an axis in one panel brushes it in all of them.

Splits the chart into small multiples: a grid of equally sized panels, one per distinct value of this data key or accessor, each drawing the chart for that value's rows. The panels share one legend, color scale, title, and timeline, color each series the same way, and hover, tooltips, and legend clicks apply across all of them. Pass false to draw a single chart. See facetConfig for the grid's layout and shared scales.

Configuration

import {ParallelCoordinates} from "@d3plus/core";

Extends Viz.

activefalse | function

The active callback function for highlighting shapes.

axisConfigobjectDefault {}

Axis config shared by every dimension's axis (titleConfig styles the dimension titles).

brushConfigobjectDefault {fill: () => backgroundInk(viz), fillOpacity: 0.12, stroke: () => backgroundInk(viz), strokeWidth: 1, width: BRUSH_WIDTH}

The brush strips: width (px), the selection's fill, fillOpacity, stroke, and strokeWidth, and inactiveOpacity, the stroke opacity of the (grayed) lines outside the brushes, which by default keep 30% of their own opacity.

brushesRecord<string, [number, number] | string[]>Default {}

The active brush filters, keyed by dimension: a numeric [min, max], or the selected categories. Brushing an axis updates it; set it to brush from code, or to {} to clear every brush.

brushingbooleanDefault true

Whether each axis can be brushed to filter the lines. Drag along an axis to brush it. To clear a brush, click its axis outside the selection, double-click the axis, or press Escape while the brushed axis has keyboard focus.

classNamestring | array.&lt;string&gt; | undefined

CSS classes added to the outermost element this chart or component draws into, next to its fixed d3plus classes, so page CSS can target it: a chart's root <svg class="d3plus-viz"> (its <canvas> with the Canvas renderer) and a standalone component's <svg>. Takes a space-separated string or an array. A new value replaces the classes the previous one added; unset adds none. Tooltips take their own tooltipConfig.className.

colorDefaultscolordefaultsconfig

Overrides the default colors used when assigning fills from data and choosing legible text colors: dark and light (the text colors picked for contrast against a background), missing (null/undefined values), on/off (true/false values), sequential (the anchor hue for magnitude ramps), and scale (the categorical palette, given as a d3 ordinal scale or an array of colors). Keys are merged into the current defaults, and a Viz passes its overrides down to the shapes and components it draws.

configd3plusconfig

Methods that correspond to the key/value pairs and returns this class.

curve"linear" | "bump"Default "linear"

"linear" draws straight segments between axes; "bump" curves into and out of each axis.

datastring | array.&lt;datapoint&gt; | object

The primary data array used to draw the visualization. The value passed should be an Array of objects or a String representing a filepath or URL to be loaded. The following filetypes are supported: csv, tsv, txt, and json.

If your data URL needs specific headers to be set, an Object with a "url" and "headers" (or any other fetch request option) may also be passed. An Object with any other key is a data row, not a request.

Additionally, a custom formatting function can be passed as a second argument to this method. This custom function will be passed the data that has been loaded, as long as there are no errors. This function should return the final array of obejcts to be used as the primary data array. For example, some JSON APIs return the headers split from the data values to save bandwidth. These would need be joined using a custom formatter.

If you would like to specify certain configuration options based on the yet-to-be-loaded data, you can also return a full config object from the data formatter (including the new data array as a key in the object).

To re-fetch a URL on an interval and redraw when its data changes, set dataPollingInterval; each poll runs the same formatter.

Defaults to an empty array ([]).

dataCutoffnumberDefault 2000

Above this many lines, hovering stops dimming the others and redraws skip their transitions. Raised from the usual 100, since following one line through a dense chart is what hovering is for.

dimensionConfigRecord<string, object>Default {}

Per-dimension options, keyed by dimension: domain, reverse, title, and any Axis config (tickFormat, ticks, scale, …).

dimensionsstring[]

The data keys to draw an axis for, in order. Defaults to every numeric key in the data except the groupBy keys and id. A key whose values aren't all numbers gets a categorical (point) axis.

facetstring | false | function

Splits the chart into small multiples: a grid of equally sized panels, one per distinct value of this data key or accessor, each drawing the chart for that value's rows. The panels share one legend, color scale, title, and timeline, color each series the same way, and hover, tooltips, and legend clicks apply across all of them. Pass false to draw a single chart. See facetConfig for the grid's layout and shared scales.

facetConfigfacetconfig

Configuration for small multiples (see facet), merged into the current config: - columns / rows: the grid's shape. Chosen by default to make the panels as large as the chart's shape allows. - padding: the space between panels, in pixels (default 20). - sort: panel order — "ascending" (default), "descending", "data" (first appearance), a comparator over facet values, or an Array of values. - scales: "shared" (default) gives every panel of a chart with axes the same x/y domains; "independent" fits each panel to its own rows. Funnel defaults to "independent" (each panel sized to its own widest stage); "shared" sizes every panel against the widest stage across all panels. PolarArea and RadialBar default to "independent" (each panel's rings and ticks fit its own values); "shared" gives every panel the same value domain. - axes: with shared scales, "outer" (default) labels the axes only along the grid's left and bottom edges; "all" labels every panel. An object sets each axis on its own, as in {x: "all", y: "outer"}: every panel labels its x axis, only the left column labels its y axis, and the panels' plot areas line up. BumpChart defaults to "all", and Marimekko labels its categories on every panel and its 0–100% share axis only along the outer edge, even with independent scales. - title: a (value, data) => string function for each panel's title, or false to hide panel titles. - titleConfig: TextBox config for the panel titles (fontSize, fontWeight, fontColor, textAnchor, padding, …).

fontFamilystring | array.&lt;string&gt;

The font family used throughout the visualization.

groupBystring | function | array.&lt;string | function&gt;

Defines the mapping between data and shape. The value can be a String matching a key in each data point (default is "id"), or an accessor Function that returns a unique value for each data point. Additionally, an Array of these values may be provided if the visualization supports nested hierarchies.

highlightfalse | function

Persistently emphasizes the data points matching the given predicate: the matching marks keep their color while every other mark is de-emphasized to a neutral gray (the "emphasis" form — highlight one series, gray the rest). Unlike hover/active (transient, opacity-based), highlight is a standing state that survives pointer movement. Pass false to clear it.

hoverfalse | function

The hover callback function for highlighting shapes on mouseover.

lineOpacitynumber | "auto"Default "auto"

The lines' stroke opacity: a number, or "auto" (the default) to fade the lines as their number grows, so dense data reads as density.

localestring | object

The locale used for all text and number formatting. Supports the locales defined in d3plus-format. The locale can be a complex Object, a locale code (like "en-US"), or a 2-digit language code (like "en"). If a 2-digit code is provided, the "findLocale" function is used to identify the most approximate locale.

onstring

Event listener for the specified event typenames. Mirrors the core d3-selection behavior.

orient"horizontal" | "vertical"Default "horizontal"

"horizontal" (default) lays the axes out left to right; "vertical" stacks them top to bottom.

parentunknown

Parent config used by the wrapper.

renderfunction

Draws the visualization given the specified configuration.

rendererboolean | "svg" | "canvas"

Selects which @d3plus/render backend paints the visible output. "svg" = SvgRenderer (default), "canvas" = CanvasRenderer. Boolean arguments both normalize to "svg".

selectstring | htmlelement

The SVG container element as a d3 selector or DOM element. Defaults to undefined.

shapeConfigd3plusconfig

Configuration object with key/value pairs applied as method calls on each shape.

thresholdnumber | function

The threshold value for bucketing small data points together, as a share of the total. On a stacked Plot, the series whose summed value across every position is under that share of the whole chart's total merge into one series, stacked on top. A bucket needs at least two items, and its tooltips list them. Off (0) by default on Plot charts.

thresholdKeystring | function

Accessor for the value used in the threshold algorithm. A stacked Plot defaults to its stacked value.

timestring | false | function

Accessor function or string key for the time dimension of each data point.

timelineDefaultstring | date | array.&lt;string | date&gt;

The starting time or range for the timeline. Can be a single Date/String, or an Array of 2 values representing the min and max.

tooltipConfigtooltipconfigDefault {tbody: (d: DataPoint) => dimensionTooltipRows(viz, d)}

Configuration for the tooltip component.

totalstring | boolean | function

Accessor function or string key for the total value displayed in the visualization.

translatefunction

Defines how informational text strings should be displayed. By default, this function will try to find the string in question (which is the first argument provided to this function) inside of an internally managed translation Object. If you'd like to override to use custom text, simply pass this method your own custom formatting function.

zoombooleanDefault false

Zooming would slide the axes out from under their brushes, so it's off by default.