d3fc-series

A collection of components for rendering data series to SVG, canvas and WebGL, including line, bar, OHLC, candlestick and more.

Main D3FC package

Installing

``bash npm install @d3fc/d3fc-series`

`API Reference`

* General API * SVG Rendering * Canvas Rendering * WebGL Rendering * Decorate Pattern * Orientation * Multi Series * Auto Bandwidth * Accessors * Line * Point * Area * Bar * Candlestick * OHLC * Boxplot * Errorbar * Heatmap * Multi * Repeat * Grouped * Stacked

This package contains a number of D3 components that render various standard series types. They all share a common API, with the typical configuration requiring x and y scales together with a number of value accessors. There are SVG, Canvas and WebGL versions of each series type, sharing the same configuration properties.

`$3`

#### SVG rendering

In order to render a line series to SVG, the data should be supplied via a data-join or datum, as follows:

`javascript const data = [ {x: 0, y: 0}, {x: 10, y: 5}, {x: 20, y: 0} ];

const line = fc.seriesSvgLine() .crossValue(d => d.x) .mainValue(d => d.y) .xScale(xScale) .yScale(yScale);

d3.select('g') .datum(data) .call(line);`

The line component is configured with the required value accessors and scales. In this case, the supplied data has x and y properties. The value accessors are invoked on each datum within the array, and simply obtain the value for their respective property. The scales are used to convert the values in the domain coordinate system (as returned by the accessors), to the screen coordinate system.

The series is rendered into a group (g) element by first selecting it, using datum to associate the data with this DOM node, then using call to invoke the series component, causing it to be rendered.

#### Canvas rendering

The seriesCanvasLine component has an API that is almost identical to its SVG counterpart, seriesSvgLine, the only difference is the addition of a context property, which is set to the context of the canvas that this series renders to.

`javascript const data = [ {x: 0, y: 0}, {x: 10, y: 5}, {x: 20, y: 0} ];

var ctx = canvas.getContext('2d');

const line = fc.seriesCanvasLine() .crossValue(d => d.x) .mainValue(d => d.y) .xScale(xScale) .yScale(yScale) .context(ctx);

line(data);`

Because D3 data-joins and data-binding only work on HTML / SVG, the canvas components are invoked directly with the supplied data. This causes the component to render itself to the canvas.

#### WebGL rendering

If this is your first time using WebGL, this collection of higher-level series components is the best place to start. Only investigate the low-level components in d3fc-webgl if you need bespoke functionality.

WebGL rendering does not yet have full feature parity with the other rendering methods. Please check the API documentation against the methods to see what is currently supported.

The seriesWebglLine component has an API that is almost identical to its canvas counterpart, seriesCanvasLine. The only difference is the context property, which requires a contextType of 'webgl'.

`javascript const data = [ {x: 0, y: 0}, {x: 10, y: 5}, {x: 20, y: 0} ];

var ctx = canvas.getContext('webgl');

const line = fc.seriesWebglLine() .crossValue(d => d.x) .mainValue(d => d.y) .xScale(xScale) .yScale(yScale) .context(ctx);

line(data);`

As with the canvas, the components are invoked directly with the supplied data. However, as with the transition from SVG to canvas, WebGL has its own subtle differences.

WebGL is based upon a pipeline of processing the data into the an appropriate format for the GPU, loading this data into the GPU and then allowing the GPU to process the data in a highly parallel fashion. When using these components, the bottlenecks in this pipeline are most commonly the pre-processing of data and the loading of data into the GPU, both of which are performed or controlled by JavaScript.

Some of this performance optimisation is addressed by the design of the components (e.g. how we pre-process the data and in to what form) and some of it necessitates the optimal use of the components by consumers (e.g. when we need to pre-process/load the data). In all cases consumers should be aiming to reduce the amount of pre-processing and loading of data to achieve the best performance.

The components offer two WebGL-specific methods to allow finer control over these processses -

* equals- This property is an equality function to control whether any pre-processing of the data is required i.e. is the data being rendered equal to the rendered on the previous call. If the data is considered equal, then the value accessors will not be invoked and the data previously loaded into the GPU will be re-used. The only exception to this is if one of the scales has a JavaScript pre-processing requirement, see the next bullet. *scaleMapper - This property is a mapping function which controls whether the scales require JavaScript pre-processing or are pure GPU implementations. If a scale has a pure GPU implemention, then the data previously loaded into the GPU will be re-used and no JavaScript processing will be required. If not, the value accessor for the scaled value as well as the scaling function itself will be invoked for each data point, the resulting data will then be transferred to the GPU before rendering.

Where datasets are static, the above properties will be sufficient to achieve the best performance. Where datasets are dynamic, splitting the datasets into separate dynamic/static datasets and rendering each as a separate series (following the above advice) will achieve the best performance. If this is not possible then dropping down to lower-level d3fc-webgl components may be required to achieve the best performance. However, this requires a considered approach and should only be attempted if the above advice can't be followed.

#### Decorate Pattern

The series components implement the decorate pattern by exposing a decorate property which is passed the data join selection, canvas context or program builder, used to render the component. This allows users of the component to perform additional rendering logic.

For further details, consult the Decorate Pattern documentation.

The following example demonstrates how the fill color of each bar can be varied via decoration. The decorate property is passed the data join selection used to construct the component's DOM. Here, the enter selection is used to set the fill color based on the index:

`javascript const color = d3.scaleOrdinal(d3.schemeCategory10);

const svgBar = fc.seriesSvgBar() .decorate((selection) => { selection.enter() .style('fill', (_, i) => color(i)); });`

Here is the same example for a canvas bar series; the way that the decorate pattern works is subtly different. For SVG components the decorate function is invoked once with the selection that renders all of the bars (or points, candlesticks, ...), with canvas, the decorate function is invoked for each of the data-points in the series.

The decorate function is passed the context, datum and index. The context is translated to the correct position and the fill color set before invoking the decorate function. After decoration the bar itself is rendered.

`javascript const canvasLine = fc.seriesCanvasBar() .decorate((context, datum, index) => { context.fillStyle = color(index); });`

And here is the same example for a WebGL series; again the pattern is subtly different. In WebGL the fill color needs to be passed down to the GPU using an attribute and then applied by a shader to the rendered bar. This is all wrapped up by the webglFillColor component.

`javascript const webglBar = fc.seriesWebglBar() .decorate((program, data) => { fc.webglFillColor() .value((_, i) => { const rgba = d3.color(color(i)); return [rgba.r / 255, rgba.g / 255, rgba.b / 255, rgba.opacity]; }) .data(data)(program); });

webglBar(data);`

Decoration can also be used to add extra elements to the series. In this example a text element is added to each bar via the enter selection.

The origin of each data-point container, which is a g element, is always set to the data-point location. As a result, the text element is translated vertically by -10, in order to position them just above each bar.

`javascript const svgBar = fc.seriesSvgBar() .decorate((selection) => { selection.enter() .append('text') .style('text-anchor', 'middle') .attr('transform', 'translate(0, -10)') .attr('fill', 'black') .text((d) => d3.format('.2f')(d)); });`

With canvas, you can also perform additional rendering to the canvas in order to achieve the same effect. Once again, the canvas origin has been translated to the origin of each data-point before the decorate function is invoked.

This example uses a point series, for a bit of variety!

`javascript const canvasLine = fc.seriesCanvasPoint() .decorate((context, datum, index) => { context.textAlign = 'center'; context.fillStyle = '#000'; context.font = '15px Arial'; context.fillText(d3.format('.2f')(datum), 0, -10); // reset the fill style for the bar rendering context.fillStyle = '#999'; });`

Whilst it is possible to do something similar with WebGL, it would be a much more involved process involving heavy customisation of the shaders. In most cases it would be easier to render the bulk of the data as a WebGL base series and then overlay a subset of the data using a decorated SVG/canvas series.

#### Orientation

Most of the series renderers support both horizontal and vertical render orientations as specified by the orient property. In order to make it easy to change the orientation of a series, and to avoid redundant and repeated property names, a change in orientation is achieved by transposing the x and y scales.

The following example shows a simple bar series rendered in its default vertical orientation:

`javascript const data = [4, 6, 8, 6, 0, 10];

const xScale = d3.scaleLinear() .domain([0, data.length]) .range([0, width]);

const yScale = d3.scaleLinear() .domain([0, 10]) .range([height, 0]);

const barSeries = fc.seriesSvgBar() .xScale(xScale) .yScale(yScale) .crossValue((_, i) => i) .mainValue((d) => d);

d3.select('g') .datum(data) .call(svgBar);`

By setting its orient property to horizontal, the x and y scales are transposed. As a result, the domain for both the x and y scale have to be switched. The following shows the changes required:

`javascript const xScale = d3.scaleLinear() .domain([0, 10]) // domain changed .range([0, width]);

const yScale = d3.scaleLinear() .domain([0, data.length]) // domain changed .range([height, 0]);

const barSeries = fc.seriesSvgBar() .xScale(xScale) .yScale(yScale) .orient('horizontal') // orient property updated .crossValue((_, i) => i) .mainValue((d) => d);`

This is part of the motivation behind naming the accessors mainValue and crossValue, rather than an orientation specific xValue / yValue.

#### Multi series

One series type that is worthy of note is the multi series. This component provides a convenient way to render multiple series, that share scales, to the same SVG or canvas.

The multi series renderers expose a series property which accepts an array of series renderers, together with the standard xScale and yScale properties. The following example shows how a multi series can be used to render both a line and bar series:

`javascript // a couple of series - value accessor configuration omitted for clarity const barSeries = fc.seriesSvgBar(); const lineSeries = fc.seriesSvgLine();

const multiSeries = fc.seriesSvgMulti() .xScale(xScale) .yScale(yScale) .series([barSeries, lineSeries]);

d3.select('g') .datum(data) .call(svgMulti);`

Notice that you do not have to set the xScale and yScale properties on each series - the scales are propagated down from the multi series.

The canvas API is very similar:

`javascript // a couple of series - value accessor configuration omitted for clarity const barSeries = fc.seriesCanvasBar(); const lineSeries = fc.seriesCanvasLine();

const multiSeries = fc.seriesCanvasMulti() .xScale(xScale) .yScale(yScale) .context(ctx) .series([barSeries, lineSeries]);

multiSeries(data)`

In this case the context is also propagated from the multi series to the children.

The multi series allows you to combine a range of different series types. If instead you have multiple data series that you want to render using the same series type, e.g. a chart containing multiple lines, the repeat series is an easier way to achieve this.

#### Auto bandwidth

A number of the series (bar, OHLC, boxplot) have a notion of 'width'. They all expose a bandwidth property where you can supply the width as a value (in the screen coordinate system).

Rather than specify a bandwidth directly, you can adapt a series with the fc.autoBandwidth component, which will either obtain the bandwidth directly from the scale, or compute it based on the distribution of data.

When used with a bandScale, the scale is responsible for computing the width of each band. The fc.autoBandwidth component invokes the bandwidth function on the scale and uses the returned value to set the bandwidth on the series.

`javascript var xScale = d3.scaleBand() .domain(data.map(d => d.x)) .rangeRound([0, width]);

var svgBar = fc.autoBandwidth(fc.seriesSvgBar()) .align('left') .crossValue(function(d) { return d.x; }) .mainValue(function(d) { return d.y; });`

Notice in the above example that the align property of the bar is set to left, which reflects the band scale coordinate system.

NOTE: The D3 point scale is a special cased band scale that has a zero bandwidth. As a result, if you use the fc.autoBandwidth component in conjunction with a point scale, the series will also have a bandwidth of zero!

When used in conjunction with a linear scale, the fc.autoBandwidth component computes the bar width based on the smallest distance between consecutive datapoints:

`javascript var xScale = d3.scaleLinear() .domain([0, 10]) .range([0, width]);

var svgBar = fc.autoBandwidth(fc.seriesSvgBar()) .crossValue(function(d) { return d.x; }) .mainValue(function(d) { return d.y; }) .widthFraction(0.5);`

The fc.autoBandwidth component, when adapting a series, adds a widthFraction property which determines the fraction of this distance that is used to set the bandwidth.

When using a multi, or repeat series, the fc.autoBandwidth component should be used to adapt the bar (or OHLC, boxplot, ...) series directly, rather than adapting the multi or repeat series.

`javascript var canvasBar = fc.seriesCanvasBar()

var canvasLine = fc.seriesCanvasLine();

var canvasMulti = fc.seriesCanvasMulti() .xScale(xScale) .yScale(yScale) .series([fc.autoBandwidth(canvasBar), canvasLine]);`

#### Accessors

All of the series expose xValues/yValues methods which return an array of all of the accessors used by the series when retrieving values for use with the xScale/yScale respectively.

`$3`

# fc.seriesSvgLine() # fc.seriesCanvasLine() # fc.seriesWebglLine()

Constructs a new line renderer for canvas, WebGL or SVG.

#### Common properties

# seriesLine.crossValue(accessorFunc) # seriesLine.mainValue(accessorFunc)

If accessorFunc is specified, sets the accessor to the specified function and returns this series. If accessorFunc is not specified, returns the current accessor. The accessorFunc(datum, index) function is called on each item of the data, returning the relevant value for the given accessor. The respective scale is applied to the value returned by the accessor before rendering.

# seriesLine.xScale(scale) # seriesLine.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesLine.orient(orientation)

If orientation is specified, sets the orientation and returns this series. If orientation is not specified, returns the current orientation. The orientation value should be either horizontal (default) or vertical.

# seriesLine.curve(scale)

The WebGL implementation does not support this property.

If curve is specified, sets the curve factory and returns this series. If curve is not specified, returns the current curve factory.

This property is rebound from line.curve.

# seriesLine.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesLine.lineWidth(width)

The SVG and canvas implementations do not support this property.

If width is specified, sets the line width and returns this series. If width is not specified, returns the current line width.

# seriesLine.equals(equals)

The SVG and canvas implementations do not support this property.

If equals is specified, sets the equality function used to compare previousData with data. The result of this check is used to control whether the data is reprojected and rescaled. If equals is not specified, returns the current equality function which defaults to always returning false indicating the data has changed.

# seriesLine.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesLine.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

If scaleMapper is specified, sets the function used to map first the xScale and then the yScale onto matched pairs of JavaScript and WebGL implementations. If equals is not specified, returns the current scale mapper which defaults to webglScaleMapper.

The returned JavaScript scale is equality checked using a reference comparison to determine whether the data needs to be rescaled. If the reference is the same as the previous render, the values associated with the scale are not rescaled.

`$3`

# fc.seriesSvgPoint() # fc.seriesCanvasPoint() # fc.seriesWebglPoint()

Constructs a new point series renderer for canvas, WebGL or SVG.

#### Common properties

# seriesPoint.crossValue(accessorFunc) # seriesPoint.mainValue(accessorFunc)

# seriesPoint.xScale(scale) # seriesPoint.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesPoint.orient(orientation)

# seriesPoint.type(type)

The WebGL implementation does not support the following shapes: diamond, star, wye.

If type is specified, sets the symbol type to the specified function or symbol type and returns this point series renderer. If type is not specified, returns the current symbol type accessor.

This property is rebound from symbol.type.

# seriesPoint.size(size)

If size is specified, sets the area to the specified function or number and returns this point series renderer. If size is not specified, returns the current size accessor.

This property is rebound from symbol.size.

# seriesPoint.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesPoint.equals(equals)

The SVG and canvas implementations do not support this property.

# seriesPoin.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesPoint.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

`$3`

# fc.seriesSvgArea() # fc.seriesCanvasArea() # fc.seriesWebglArea()

Constructs a new area series renderer for canvas, WebGL or SVG.

#### Common properties

# seriesArea.crossValue(accessorFunc) # seriesArea.mainValue(accessorFunc) # seriesArea.baseValue(accessorFunc)

# seriesArea.orient(orientation)

The WebGL implementation does not support this property.

# seriesArea.xScale(scale) # seriesArea.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesArea.curve(scale)

The WebGL implementation does not support this property.

If curve is specified, sets the curve factory and returns this series. If curve is not specified, returns the current curve factory.

# seriesArea.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesArea.equals(equals)

The SVG and canvas implementations do not support this property.

# seriesArea.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesArea.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

`$3`

# fc.seriesSvgBar() # fc.seriesCanvasBar() # fc.seriesWebglBar()

Constructs a new bar series renderer for canvas, WebGL or SVG.

#### Common properties

# seriesBar.crossValue(accessorFunc) # seriesBar.mainValue(accessorFunc) # seriesBar.baseValue(accessorFunc)

# seriesBar.orient(orientation)

The WebGL implementation does not support this property.

# seriesBar.align(alignment)

The WebGL implementation does not support this property.

If alignment is specified, sets the alignment and returns this series. If alignment is not specified, returns the current alignment. The alignment value should be left, right or center (default) and describes how the alignment of each bar with respect to the central value.

# seriesBar.xScale(scale) # seriesBar.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesBar.bandwidth(bandwidthFunc)

If bandwidthFunc is specified, sets the bandwidth function and returns this series. If bandwidthFunc is not specified, returns the current bandwidth function.

# seriesBar.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesBar.equals(equals)

The SVG and canvas implementations do not support this property.

# seriesBar_.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesBar.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

`$3`

# fc.seriesSvgCandlestick() # fc.seriesCanvasCandlestick() # fc.seriesWebglCandlestick()

Constructs a new candlestick renderer for canvas, WebGL or SVG.

# seriesCandlestick.crossValue(accessorFunc) # seriesCandlestick.highValue(accessorFunc) # seriesCandlestick.lowValue(accessorFunc) # seriesCandlestick.openValue(accessorFunc) # seriesCandlestick.closeValue(accessorFunc)

# seriesCandlestick.xScale(scale) # seriesCandlestick.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesCandlestick.bandwidth(bandwidthFunc)

If bandwidthFunc is specified, sets the bandwidth function and returns this series. If bandwidthFunc is not specified, returns the current bandwidth function.

# seriesCandlestick.align(alignment)

The WebGL implementation does not support this property.

# seriesCandlestick.decorate(decorateFunc)

If decorateFunc is specified, sets the decorator function to the specified function, and returns this series. If decorateFunc is not specified, returns the current decorator function.

# seriesCandlestick.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesCandlestick.lineWidth(width)

The SVG and canvas implementations do not support this property.

If width is specified, sets the line width and returns this series. If width is not specified, returns the current line width.

# seriesCandlestick.equals(equals)

The SVG and canvas implementations do not support this property.

# seriesCand.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesCandlestick.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

`$3`

# fc.seriesSvgOhlc() # fc.seriesCanvasOhlc() # fc.seriesWebglOhlc()

Constructs a new OHLC renderer for canvas, WebGL or SVG.

#### Common properties

# seriesOhlc.crossValue(accessorFunc) # seriesOhlc.highValue(accessorFunc) # seriesOhlc.lowValue(accessorFunc) # seriesOhlc.openValue(accessorFunc) # seriesOhlc.closeValue(accessorFunc)

# seriesOhlc.xScale(scale) # seriesOhlc.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesOhlc.bandwidth(bandwidthFunc)

If bandwidthFunc is specified, sets the bandwidth function and returns this series. If bandwidthFunc is not specified, returns the current bandwidth function.

# seriesOhlc.align(alignment)

The WebGL implementation does not support this property.

# seriesOhlc.decorate(decorateFunc)

If decorateFunc is specified, sets the decorator function to the specified function, and returns this series. If decorateFunc is not specified, returns the current decorator function.

# seriesOhlc.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesOhlc.lineWidth(width)

The SVG and canvas implementations do not support this property.

If width is specified, sets the line width and returns this series. If width is not specified, returns the current line width.

# seriesOhlc.equals(equals)

The SVG and canvas implementations do not support this property.

# seriesOhlc.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesOhlc.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

`$3`

# fc.seriesSvgBoxPlot() # fc.seriesCanvasBoxPlot() # fc.seriesWebglBoxPlot()

Constructs a new boxplot renderer for canvas, WebGL or SVG.

#### Common properties

# seriesBoxPlot.crossValue(accessorFunc) # seriesBoxPlot.medianValue(accessorFunc) # seriesBoxPlot.upperQuartileValue(accessorFunc) # seriesBoxPlot.lowerQuartileValue(accessorFunc) # seriesBoxPlot.highValue(accessorFunc) # seriesBoxPlot.lowValue(accessorFunc)

# seriesBoxPlot.orient(orientation)

The WebGL implementation does not support this property.

# seriesBoxPlot.xScale(scale) # seriesBoxPlot.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesBoxPlot.bandwidth(bandwidthFunc)

If bandwidthFunc is specified, sets the bandwidth function and returns this series. If bandwidthFunc is not specified, returns the current bandwidth function.

# seriesBoxPlot.align(alignment)

The WebGL implementation does not support this property.

# seriesBoxPlot.cap(capFunc)

If capFunc is specified, sets the cap function and returns this series. If capFunc is not specified, returns the current cap function. The capFunc(item, index) function is called on each item of the data, and returns the proportion of the box width that the caps width should be.

# seriesBoxPlot.decorate(decorateFunc)

If decorateFunc is specified, sets the decorator function to the specified function, and returns this series. If decorateFunc is not specified, returns the current decorator function.

# seriesBoxplot.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesBoxplot.lineWidth(width)

The SVG and canvas implementations do not support this property.

If width is specified, sets the line width and returns this series. If width is not specified, returns the current line width.

# seriesBoxplot.equals(equals)

The SVG and canvas implementations do not support this property.

# seriesBoxp.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesBoxplot.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

`$3`

# fc.seriesSvgErrorBar() # fc.seriesCanvasErrorBar() # fc.seriesWebglErrorBar()

Constructs a new error bar renderer for canvas, WebGL or SVG.

#### Common properties

# seriesErrorBar.crossValue(accessorFunc) # seriesErrorBar.highValue(accessorFunc) # seriesErrorBar.lowValue(accessorFunc)

# seriesErrorBar.orient(orientation)

The SVG implementation does not support this property.

# seriesErrorBar.xScale(scale) # seriesErrorBar.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesErrorBar.bandwidth(bandwidthFunc)

If bandwidthFunc is specified, sets the bandwidth function and returns this series. If bandwidthFunc is not specified, returns the current bandwidth function.

# seriesErrorBar.align(alignment)

The WebGL implementation does not support this property.

# seriesErrorBar.decorate(decorateFunc)

If decorateFunc is specified, sets the decorator function to the specified function, and returns this series. If decorateFunc is not specified, returns the current decorator function.

# seriesErrorBar.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

# seriesErrorBar.lineWidth(width)

The SVG and canvas implementations do not support this property.

If width is specified, sets the line width and returns this series. If width is not specified, returns the current line width.

# seriesErrorBar.equals(equals)

The SVG and canvas implementations do not support this property.

# seriesErro.pixelRatio(pixelRatio)

The SVG and canvas implementations do not support this property.

If pixelRatio is specified, sets the factor used to scale any pixel values. If pixelRatio is not specified returns the current value.

# seriesErrorBar.scaleMapper(scaleMapper)

The SVG and canvas implementations do not support this property.

`$3`

# fc.seriesSvgHeatmap() # fc.seriesCanvasHeatmap()

Constructs a new heatmap series renderer for either canvas or SVG.

#### Common properties

# seriesHeatmap.crossValue(accessorFunc) # seriesHeatmap.highValue(accessorFunc) # seriesHeatmap.colorValue(accessorFunc)

# seriesHeatmap.xScale(scale) # seriesHeatmap.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesHeatmap.colorInterpolate(interpolate)

If colorInterpolate is specified, sets the interpolator used to map color values to colors and returns this series. If colorInterpolate is not specified, returns the current interpolator.

# seriesHeatmap.xBandwidth(bandwidthFunc) # seriesHeatmap.yBandwidth(bandwidthFunc)

If bandwidthFunc is specified, sets the bandwidth function and returns this series. If bandwidthFunc is not specified, returns the current bandwidth function.

# seriesHeatmap.yAlign(alignment) # seriesHeatmap.xAlign(alignment)

The WebGL implementation does not support this property.

# seriesHeatmap.decorate(decorateFunc)

If decorateFunc is specified, sets the decorator function to the specified function, and returns this series. If decorateFunc is not specified, returns the current decorator function.

# seriesErrorBar.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

`$3`

# fc.seriesSvgMulti() # fc.seriesCanvasMulti() # fc.seriesWebglMulti()

Constructs a new multi series renderer for canvas, WebGL or SVG.

#### Common properties

# seriesMulti.series(seriesArray)

If seriesArray is specified, sets the array of series that this multi series should render and returns this series. If seriesArray is not specified, returns the current array of series.

# seriesMulti.xScale(scale) # seriesMulti.yScale(scale)

If scale is specified, sets the scale and returns this series. If scale is not specified, returns the current scale.

# seriesMulti.mapping(mappingFunc)

If mappingFunc is specified, sets the mapping function to the specified function, and returns this series. If mappingFunc is not specified, returns the current mapping function.

When rendering the multi-series, the mapping function is invoked once for each of the series supplied via the series property. The purpose of the mapping function is to return the data supplied to each of these series. The default mapping is the identity function, (d) => d, which results in each series being supplied with the same data as the multi-series component.

The mapping function is invoked with the data bound to the multi-series, (data), the index of the current series (index) and the array of series (series). A common pattern for the mapping function is to switch on the series type. For example, a multi-series could be used to render a line series together with an upper bound, indicated by a line annotation. In this case, the following would be a suitable mapping function:

`javascript const multi = fc.seriesSvgMulti() .series([line, annotation) .mapping((data, index, series) => { switch(series[index]) { case line: return data.line; case annotation: return data.upperBound; } });`

# seriesMulti.decorate(decorateFunc)

If decorateFunc is specified, sets the decorator function to the specified function, and returns this series. If decorateFunc is not specified, returns the current decorator function.

With the SVG multi series, the decorate function is invoked once, with the data join selection that creates the outer container. With the canvas multi series the decorate function is invoked for each of the associated series.

# seriesMulti.context(ctx)

The SVG implementation does not support this property.

If ctx is specified, sets the canvas context and returns this series. If ctx is not specified, returns the current context.

`$3`

# fc.seriesSvgRepeat() # fc.seriesCanvasRepeat() # fc.seriesWebglRepeat()

Constructs a new repeat series renderer for canvas, WebGL or SVG.

The repeat series is very similar in function to the multi series, both are designed to render multiple series from the same bound data. The repeat series uses the same series type for each data series, e.g. multiple lines series, or multiple area series.

The repeat series expects the data to be presented as an array of arrays. The following example demonstrates how it can be used to render multiple line series:

`javascript const data = [ [1, 3, 4], [4, 5, 6] ];

const line = fc.seriesSvgLine();

const repeatSeries = fc.seriesSvgRepeat() .xScale(xScale) .yScale(yScale) .series(line);

d3.select('g') .datum(data) .call(repeatSeries);`

The repeat series also exposes an orient property which determines the 'orientation' of the series within the bound data. In the above example, setting orient to horizontal would result in the data being rendered as two series of three points (rather than three series of two points).

#### Common properties

# seriesRepeat.series(series)

If series is specified, sets the series that this repeat series should render and returns this series. If series is not specified, returns the current series.

For the WebGL implementation only, series can be specified as a function which when invoked returns a new series instance. This allows the repeat series to allocate a series instance per data series, preventing the unnecessary cache-evictions which can occur if only one series instance is used.

# seriesRepeat.orient(orientation)

# seriesRepeat.xScale(scale)
# seriesRepeat.yScale(scale)
# seriesRepeat.decorate(decorateFunc)
# seriesRepeat.context(ctx)

Please refer to the multi series for the documentation of these properties.

$3

# fc.seriesSvgGrouped(adaptedSeries)
# fc.seriesCanvasGrouped(adaptedSeries)

Construct

d3fc-series

A collection of components for rendering data series to SVG, canvas and WebGL, including line, bar, OHLC, candlestick and more.