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The Digital (Step) Line Series

Digital, or Step Line Series can be created using the FastLineRenderableSeries📘 type, and setting the isDigitalLine📘 flag to true.

Above: The JavaScript Digital Line Chart example from the SciChart.js Demo

Create a Digital (Step) Line Series

To create a JavaScript Digital Line Chart with SciChart.js, use the following code:

// Demonstrates how to create a digitral line chart with SciChart.js
const {
SciChartSurface,
NumericAxis,
FastLineRenderableSeries,
XyDataSeries,
SciChartJsNavyTheme
} = SciChart;
// or, for npm, import { SciChartSurface, ... } from "scichart"

const { wasmContext, sciChartSurface } = await SciChartSurface.create(divElementId, {
theme: new SciChartJsNavyTheme()
});

sciChartSurface.xAxes.add(new NumericAxis(wasmContext));
sciChartSurface.yAxes.add(new NumericAxis(wasmContext));

const xValues = [];
const yValues = [];
for (let i = 0; i < 100; i++) {
xValues.push(i);
yValues.push(Math.sin(i * 0.1));
}

const lineSeries = new FastLineRenderableSeries(wasmContext, {
dataSeries: new XyDataSeries(wasmContext, {
xValues,
yValues
}),
stroke: "#FF6600",
strokeThickness: 5,
isDigitalLine: true // enable a digital (step) line
});
sciChartSurface.renderableSeries.add(lineSeries);

This results in the following:

In the code above:

Render a Gap in a Digital (Step) Line Series

tip

It is possible to have null points or gaps in a Digital Line Series by passing a data point with a NaN value as the Y value. Please refer to the Common Series Features - Draw Gaps in Series article for more details.

Add Point Markers onto a Digital (Step) Line Series

It is possible to put scatter point markers of varying type (Ellipse, Square, Triangle, Cross, Custom) onto a Digital Line via the PointMarker API. To learn more, see the documentation page Drawing PointMarkers on Series.

tip

To learn more about the types of Point Marker in SciChart.js, see the Point Markers API documentation.

There is also a dedicated Scatter Series type and a Bubble Series type with some more options.

Painting Digital Line Segments with Different Colors

tip

It is possible to define the colour of line segments individually using the PaletteProvider API.

For more info on how to do this, see the PaletteProvider - Per-point colouring of Line Charts documentation page.