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# BNNS.ActivationFunction.silu

An activation function that returns the sigmoid linear unit (SiLU) function of its input.

```
case silu
```

## Discussion

This constant defines an activation function that returns values using the following operation:

```swift
SiLU(x) = x * sigmoid(x)
```

The following illustrates the output that the activation function generates from inputs in the range `-10...10`:

![Graph that shows input values for the activation function on horizontal axis and its output values on vertical axis. ](images/com.apple.accelerate/media-3786739@2x.png)

## See Also

[`var BNNSActivationFunctionSiLU: BNNSActivationFunction`](/documentation/Accelerate/BNNSActivationFunctionSiLU)

An activation function that returns the sigmoid linear unit (SiLU) function of its input.


---

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