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# custom(of:label:_:)

Computes a custom aggregation from a single metric’s results.

```
mutating func custom(of metric: Metric, label: String, _ body: ([Double]) -> Double)
```

## Parameters

`metric`

The metric to aggregate.

`label`

The label for this statistic in the aggregated results.

`body`

A closure that receives the metric’s values and returns a computed statistic.

---

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