# Box plot in a table

> Show the spread of a measure as a box plot in each table row.

A box plot shows how a measure is spread: the middle half of the values as a box, the median as a line in the box, and whiskers for the rest. This template draws one in every row of a table.

:::info Set up first
Add the function library and import it into your dataset first. See [SVG charts in tables](./index.md).
:::

## Add the metric

Call `SVG.Viz.Boxplot` from a metric of type `text`, and wrap it in `SVG.Html.Box` to fix the size in the cell.

```aml
metric box_plot {
  label: 'Box Plot'
  type: 'text'
  definition: @aql
    SVG.Html.Box(
      300, 50,
      SVG.Viz.Boxplot(
        products,
        products.id,
        count(orders.id),
        '#22cf13',
        null,
        300,
        50
      )
    )
  ;;
}
```

## Parameters

### `SVG.Viz.Boxplot`

`SVG.Viz.Boxplot` takes these parameters in order.

| Parameter | Type | What it is |
|---|---|---|
| `pAxisModel` | `model` | The model whose rows the statistics run over, such as `products`. |
| `pAxisRef` | `dimension` | The dimension that splits the model into the points of the plot, such as `products.id`. |
| `pMeasureRef` | `number` | The measure to plot, such as `count(orders.id)`. |
| `pFillColor` | `text` | Box fill color. `null` uses the default blue. |
| `pStrokeColor` | `text` | Line color. `null` uses `#333333`. |
| `pWidth` | `number` | Width of the chart's drawing grid. Sets the proportions, not the display size. `null` uses 120. |
| `pHeight` | `number` | Height of the chart's drawing grid. Sets the proportions, not the display size. `null` uses 48. |

### `SVG.Html.Box`

`SVG.Html.Box` sets how big the chart looks in the table cell. Without it, the chart stretches to the full width of the cell.

| Parameter | Type | What it is |
|---|---|---|
| `pWidth` | `number` | Display width in pixels. |
| `pHeight` | `number` | Display height in pixels. |
| `pContents` | `text` | The chart to show, such as the result of `SVG.Viz.Boxplot`. |

The chart scales to fit this box and keeps its proportions. Use the same width-to-height ratio as the chart's `pWidth` and `pHeight`, or the chart leaves empty space around it.

## Use it in a table

Put the metric next to the dimension you want a row for.

```aql
explore {
  dimensions {
    product_name: products.name
  }
  measures {
    box_plot: box_plot
  }
}
```

## How to read it

- The box runs from the 25th to the 75th percentile.
- The line in the box is the median.
- The whiskers reach the lowest and highest values within 1.5 times the box width. They stop at the minimum or maximum if those are closer.
- Circles beyond the whiskers are outliers.
- The scale runs from the minimum to the maximum of the row, so each row fills its own width.