apache/echarts · error

Invalid coords {}. Lines must have 2d coords array in data i

Error message

Invalid coords {}. Lines must have 2d coords array in data item.

What it means

DEV-only guard in LinesSeries._getCoordsFromItemModel: a 'lines' series data item must provide coords as a 2D array (an array of [x,y] pairs), because each data item may itself contain multiple polyline segments. The check verifies coords is an Array, non-empty, and coords[0] is itself an Array. Stripped in production.

Source

Thrown at src/chart/lines/LinesSeries.ts:217

            }
            else {
                this._flatCoords = concatArray(this._flatCoords, result.flatCoords);
                this._flatCoordsOffset = concatArray(this._flatCoordsOffset, result.flatCoordsOffset);
            }
            params.data = new Float32Array(result.count);
        }

        this.getRawData().appendData(params.data);
    }

    _getCoordsFromItemModel(idx: number) {
        const itemModel = this.getData().getItemModel<LinesDataItemOption>(idx);
        const coords = (itemModel.option instanceof Array)
            ? itemModel.option : itemModel.getShallow('coords');

        if (__DEV__) {
            if (!(coords instanceof Array && coords.length > 0 && coords[0] instanceof Array)) {
                throw new Error(
                    'Invalid coords ' + JSON.stringify(coords) + '. Lines must have 2d coords array in data item.'
                );
            }
        }
        return coords;
    }

    getLineCoordsCount(idx: number) {
        if (this._flatCoordsOffset) {
            return this._flatCoordsOffset[idx * 2 + 1];
        }
        else {
            return this._getCoordsFromItemModel(idx).length;
        }
    }

    getLineCoords(idx: number, out: number[][]) {
        if (this._flatCoordsOffset) {

View on GitHub (pinned to 30076aedcd)

Solutions

1. Provide coords as [[x1,y1],[x2,y2],...]
2. Or pass the data item itself as a 2D array
3. Validate the data shape before setOption

Example fix

// before
{ type: 'lines', data: [{ coords: [116, 39] }] }

// after
{ type: 'lines', data: [{ coords: [[116, 39], [121, 31]] }] }

(option.series || []).filter((s: any) => s.type === 'lines').forEach((s: any) => {
  (s.data || []).forEach((d: any) => {
    const c = Array.isArray(d) ? d : d && d.coords;
    if (!(Array.isArray(c) && c.length > 0 && Array.isArray(c[0]))) {
      console.error('[lines] data item has invalid coords', d);
    }
  });
});

const is2DCoords = (c: unknown): c is number[][] =>
  Array.isArray(c) && c.length > 0 && Array.isArray(c[0]);

When it happens

Trigger: Passing a data item like { coords: [116, 39] } (flat pair), { coords: 'foo' }, omitting coords, or supplying a 1D array of numbers.

Common situations: Confusing the 'lines' series data shape with the regular 'line' series; data export that flattened nested arrays; truncating coords during serialization.

Related errors

• Invalid data format.
• Unknown coordinate system {}
• key must not be "{}"
• Heatmap must use with visualMap
• Heatmap on cartesian must have two category axes

AI-assisted analysis of apache/echarts@30076aedcd (2026-08-12). Data as JSON: /api/errors/df395771af90fc16. Report an issue: GitHub.