Tornado.

COMMUNITY

Compare two groups on opposite sides of a center line.

Live preview21 feature examples

LIVE EXAMPLE

Compare two groups

Match the page theme
Interact with the chart to see selection and range-change results here.
OptionsChanges are reflected in the preview and code.
Appearance and style3
Axes and grid lines5
Legend and interaction12
Title and dimensions3

Place groups on either side of the central reference line. All values are sample data.

View code
Current preview
<div id="chart-container" style="width: 100%; min-width: 0;"></div>

<script type="module">
  import { defineCustomElement as define0 } from '@syidax/advanced/components/sy-tornado-chart.js';
  define0();

  const specs = [
    {
      "id": "example-chart",
      "tag": "sy-tornado-chart",
      "props": {
        "engine": "standard",
        "data": [
          {
            "category": "20s",
            "values": [35, 42]
          },
          {
            "category": "30s",
            "values": [52, 48]
          },
          {
            "category": "40s",
            "values": [41, 36]
          },
          {
            "category": "50s",
            "values": [28, 32]
          }
        ],
        "width": 640,
        "height": 360,
        "brandPosition": "bottom-right",
        "brandLogo": ""
      }
    }
  ];
  const container = document.querySelector('#chart-container');
  const elements = specs.map(({ tag, id, props }) => {
    const element = document.createElement(tag);
    element.id = id;
    Object.assign(element, props);
    element.setAttribute('aria-label', 'tornado example chart');
    return element;
  });
  container.replaceChildren(...elements);
  const chart = elements.at(-1);
  const onEvent = event => {
    console.log('pointClick', event.detail);
  };
  chart.addEventListener('pointClick', onEvent);
  const observer = new ResizeObserver(([entry]) => {
    const width = Math.max(160, Math.floor(entry.contentRect.width));
    elements.forEach(element => { element.width = width; });
  });
  observer.observe(container);

  // In an SPA, call this function when the view is disposed.
  function disposeChart() {
    observer.disconnect();
    chart.removeEventListener('pointClick', onEvent);
    container.replaceChildren();
  }
</script>

Usage and data

#

Use for two groups with shared categories, such as age bands or products.

The two sides separate direction. Do not arbitrarily negate the input values.

Data contract

PropertyInput format
dataAn array of { category, values: [left, right] }.
colorSet group colors as [left, right].
groupsNames for the two groups.

Updating data

Assign a new array or object to the property instead of mutating values inside an array. Chart events provide selection results through event.detail. When disposing of the view, clean up ResizeObserver and event listeners registered by your app.

Add to your interface

#

The code tabs below the preview contain the full data, options, event bindings, and responsive sizing for the current example. Copy them into an app project, such as Vite, that can resolve the installed packages.

Shared sy-chart API versus direct tags

API reference

#

The full public API for sy-tornado-chart. Pass objects and arrays as JavaScript properties. Select a name to view usage code and type definitions.

Key properties

Attribute / PropertyType / DefaultDescription
ReadonlyArray<TornadoDatum>Default: []An array of { category, values: [left, right] }.
ReadonlyArray<string>Default: []Names for the two groups.
numberDefault: 680Chart width in pixels. Update with ResizeObserver when the container changes.
numberDefault: 380Chart height in pixels.
brandLogostringDefault: undefinedThe default is the Syidax logo. With the Pro chart.branding entitlement, use none or a PNG, JPEG, or WebP data URL.
brandPosition'top-left' | 'top-right' | 'bottom-left' | 'bottom-right'Default: 'bottom-right'The corner where the logo is anchored. Applies equally to Community and Pro, on screen and in image exports.
string | ReadonlyArray<string>Default: ''Set group colors as [left, right].
leftLabelstringDefault: undefinedDeprecated fallback: prefer `groups[0]`.
rightLabelstringDefault: undefinedDeprecated fallback: prefer `groups[1]`.
barPaddingnumberDefault: 0.3Vertical gap between bars as a fraction of each band (0..0.6).
xLabelMode'auto' | 'all' | 'thin' | 'rotate' | 'none'Default: undefinedHow crowded category-axis labels are decluttered. Default 'auto' thins labels horizontally.
xLabelRotationnumberDefault: undefinedExplicit category-label rotation in degrees (respected as a floor).
valueAxisLabelstringDefault: undefinedSet as an HTML attribute or JavaScript property. type: string.
gridLinesCartesianGridLinesInputDefault: undefinedAllowed values: auto, off. Default: undefined.
CartesianCrosshairInputDefault: undefinedCrosshair that follows the cursor across the plot. `true`/`'auto'` enables a snapping line; pass an object to set mode/snap/color/dash.
chartTitlestringDefault: undefinedThe title inside the chart. Explain the data's unit and meaning alongside it.
chartSubtitlestringDefault: undefinedThe subtitle inside the chart.
tooltipEnabledbooleanDefault: trueSet as an HTML attribute or JavaScript property. type: boolean.
CartesianTooltipInputDefault: undefinedTooltip settings for pointer-driven values, position, and content.
animatedbooleanDefault: falseWhether to animate initial display and data changes.
animationDurationnumberDefault: 600Animation duration in milliseconds.
animationEasingTornadoChartEasingDefault: 'ease-out'Allowed values: linear, ease-out, ease-in, ease-in-out. Default: 'ease-out'.
animationTypeTornadoChartAnimationTypeDefault: undefinedAllowed values: initial, update. Default: undefined.
Other properties 12
Attribute / PropertyType / DefaultDescription
ReadonlyArray<string>Default: undefinedPass as a JavaScript property. type: ReadonlyArray<string>.
leftValuesTornadoChartValuesDefault: undefinedDeprecated fallback: prefer `data` + `groups`, matching dot-plot.
rightValuesTornadoChartValuesDefault: undefinedDeprecated fallback: prefer `data` + `groups`, matching dot-plot.
xLabelMaxCountnumberDefault: undefinedHard cap on the number of category labels shown.
tooltipFormat(detail: TornadoChartPointerEventDetail) => stringDefault: undefinedPass as a JavaScript property. type: (detail: TornadoChartPointerEventDetail) => string.
enableMouseTrackingbooleanDefault: trueSet as an HTML attribute or JavaScript property. type: boolean.
streamSourceTornadoChartStreamSourceDefault: undefinedA stream source for live data. Check the contract for the specific type.
streamWindownumberDefault: undefinedThe streaming data range to keep visible.
streamMaxnumberDefault: undefinedThe maximum number of streaming data points to retain.
TornadoChartEngineModeDefault: 'auto'Renderer selection: auto, standard, or pro. Engine selection is separate from permission to use a Pro chart type.
proThresholdnumberDefault: 50_000Set as an HTML attribute or JavaScript property. type: number.
TornadoChartUnavailableBehaviourDefault: 'fallback'Allowed values: fallback, error, throw. Default: 'fallback'.
Events 14
EventsDetail typeDescription
TornadoChartRenderResult & { tier: TornadoChartEngineTier }Emits rendering results in detail when chart drawing completes.
TornadoChartPointerEventDetailA point selection event. Read the selected data and index from CustomEvent.detail.
TornadoChartPointerEventDetail | nullCustomEvent.detail type: TornadoChartPointerEventDetail | null. Event names are case-sensitive.
CartesianCrosshairEventDetail | nullCustomEvent.detail type: CartesianCrosshairEventDetail | null. Event names are case-sensitive.
ChartPointContextMenuEventDetail<TornadoChartPointerEventDetail>CustomEvent.detail type: ChartPointContextMenuEventDetail<TornadoChartPointerEventDetail>. Event names are case-sensitive.
{ count: number }CustomEvent.detail type: { count: number }. Event names are case-sensitive.
{ dropped: number }CustomEvent.detail type: { dropped: number }. Event names are case-sensitive.
voidCustomEvent.detail type: void. Event names are case-sensitive.
voidCustomEvent.detail type: void. Event names are case-sensitive.
voidCustomEvent.detail type: void. Event names are case-sensitive.
CartesianTooltipEventDetailWhether to display the built-in tooltip.
voidCustomEvent.detail type: void. Event names are case-sensitive.
CartesianTooltipActionEventDetailCustomEvent.detail type: CartesianTooltipActionEventDetail. Event names are case-sensitive.
CartesianSeriesOutsideClickEventDetailCustomEvent.detail type: CartesianSeriesOutsideClickEventDetail. Event names are case-sensitive.
Methods 16

Stencil methods return Promises. Use await within an async function to read the result.

Method / ArgumentsReturn typeDescription
Promise<TornadoChartRenderResult>An asynchronous method. Check the argument and return types below.
Promise<TornadoChartEngineTier>An asynchronous method. Check the argument and return types below.
data: ReadonlyArray<TornadoDatum> | TornadoChartValues, rightValues?: TornadoChartValuesPromise<void>An asynchronous method. Check the argument and return types below.
datum: TornadoRowDatumPromise<void>An asynchronous method. Check the argument and return types below.
data: ReadonlyArray<TornadoRowDatum>Promise<void>An asynchronous method. Check the argument and return types below.
count: numberPromise<void>An asynchronous method. Check the argument and return types below.
data: ReadonlyArray<TornadoRowDatum>Promise<void>An asynchronous method. Check the argument and return types below.
Promise<TornadoChartStreamSource | undefined>An asynchronous method. Check the argument and return types below.
options: { duration?: number; easing?: TornadoChartEasing; enabled?: boolean; type?: TornadoChartAnimationType }Promise<void>An asynchronous method. Check the argument and return types below.
Promise<void>An asynchronous method. Check the argument and return types below.
Promise<void>An asynchronous method. Check the argument and return types below.
Promise<void>An asynchronous method. Check the argument and return types below.
cssX: number, cssY: numberPromise<TornadoChartPointerEventDetail | null>An asynchronous method. Check the argument and return types below.
index: number, seriesIndex?: number | TornadoChartSidePromise<CartesianTooltipEventDetail | null>An asynchronous method. Check the argument and return types below.
Promise<void>An asynchronous method. Check the argument and return types below.
Promise<ChartEngineStatus>Requested engine vs what runs, and why (CHART-ADD-08): always Standard (this type has no WebGPU renderer); read without side effects, never consults the license.