> ## Documentation Index
> Fetch the complete documentation index at: https://docs.meibel.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Extracting chart data

> Read a chart's digitized series, values, and recognized labels from the structured result

When a document contains charts, you often want the numbers behind them rather than an image. Meibel digitizes line and scatter charts into their series, reconciles those values with a vision model, and recovers the text labels drawn on the chart. All of it arrives on the chart element in the structured result. This guide reads it in code.

For how chart digitization works and what it recovers, see [charts, formulas, and vision models](/document-parsing/concepts/charts-and-vision).

## Prerequisites

* A completed parse job for a document that contains charts.
* The structured result, fetched with `get_structured_result`, which is where chart data is exposed.

## Find the charts

A chart is an element with the `Chart` label. When its geometry was recovered, the element carries the digitized plot on `chart_data`. Walk the pages and collect the chart elements that have it.

<CodeGroup>
  ```python Python theme={null}
  from meibel import ParseLayoutLabel

  result = client.documents.get_structured_result(job_id=job_id)

  charts = [
      el
      for page in result.pages
      for el in page.elements
      if el.label == ParseLayoutLabel.CHART and el.chart_data
  ]
  print(f"Found {len(charts)} charts with data")
  ```

  ```typescript TypeScript theme={null}
  const result = await client.documents.getStructuredResult(jobId);

  const charts = result.pages
    .flatMap((page) => page.elements)
    .filter((el) => el.label === 'Chart' && el.chartData);
  console.log(`Found ${charts.length} charts with data`);
  ```
</CodeGroup>

## Read the series and points

A chart's `chart_data` holds its series, and each series holds its points. Each point carries an `x` and a `y` in data units. When the x-axis is categorical, the chart also lists its `categories`, and a point's `x` is the index into that list.

<CodeGroup>
  ```python Python theme={null}
  for element in charts:
      chart = element.chart_data
      for series in chart.series:
          name = series.name or "series"
          values = [(p.x, p.y) for p in series.points]
          print(name, values)
      if chart.categories:
          print("categories:", chart.categories)
  ```

  ```typescript TypeScript theme={null}
  for (const element of charts) {
    const chart = element.chartData;
    for (const series of chart.series) {
      const name = series.name ?? 'series';
      const values = series.points.map((p) => [p.x, p.y]);
      console.log(name, values);
    }
    if (chart.categories.length) console.log('categories:', chart.categories);
  }
  ```
</CodeGroup>

## Read the recognized labels

The text on a chart, such as axis titles and data labels, is recovered onto the element's `ocr_text`. Each entry carries the recognized `text`, its `confidence`, and a `source` of `PdfText` when it came from the document's own text or `Ocr` when it was read from the image. Because `ocr_text` is a sibling of `chart_data`, it is present even on a chart whose geometry could not be digitized.

```python Python theme={null}
for page in result.pages:
    for element in page.elements:
        if element.label == ParseLayoutLabel.CHART:
            for label in element.ocr_text or []:
                print(label.source, label.confidence, label.text)
```

## Check confidence and warnings

Digitization is an estimate, and the chart records how much to trust it. Each chart carries an `overall_confidence` and a `warnings` list. A warning is raised when a recognized value disagrees with the geometry, or when a series cannot be assigned to a left or right axis. Read both before treating the values as exact.

```python Python theme={null}
for element in charts:
    chart = element.chart_data
    print("confidence:", chart.overall_confidence)
    for w in chart.warnings:
        print("warning:", w)
```

<Warning>
  Chart values are recovered from geometry and vision model recognition, so they are estimates rather than the source data. Gate on `overall_confidence` and surface `warnings` before using the numbers in anything that assumes exact figures.
</Warning>

## Related

<CardGroup cols={2}>
  <Card title="Charts, formulas, and vision models" icon="chart-line" href="/document-parsing/concepts/charts-and-vision">
    How chart data is digitized and reconciled.
  </Card>

  <Card title="Output schema" icon="code" href="/document-parsing/reference/output-schema">
    The full chart data field definitions.
  </Card>
</CardGroup>