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# evaluate(x:)

Provides the height of the envelope for an input value.

```
func evaluate(x: Double) -> Double
```

## Parameters

`x`

A value within the envelope’s domain. The envelope clamps this parameter to a value within [`domain`](/documentation/PHASE/PHASEEnvelope/domain).

## Return Value

The curve’s height for the argument *x* value.

---

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