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# BNNS.ActivationLayer

A layer object that wraps an activation filter and manages its deinitialization.

```
class ActivationLayer
```

## Topics

### Creating an Activation Layer

[`convenience init?(function: BNNS.ActivationFunction, input: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, filterParameters: BNNSFilterParameters?)`](/documentation/Accelerate/BNNS/ActivationLayer/init(function:input:output:filterParameters:))

Returns a new activation layer.

### Specifying an Activation Function

[`enum ActivationFunction`](/documentation/Accelerate/BNNS/ActivationFunction)

Constants that describe activation functions.

### Directly Applying Activation

[`static func applyActivation(activation: BNNS.ActivationFunction, input: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, batchSize: Int, filterParameters: BNNSFilterParameters?) throws`](/documentation/Accelerate/BNNS/applyActivation(activation:input:output:batchSize:filterParameters:))

Applies the specified activation function.

### Initializers

[`convenience init?(function: BNNS.ActivationFunction, axes: [Int], input: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, filterParameters: BNNSFilterParameters?)`](/documentation/Accelerate/BNNS/ActivationLayer/init(function:axes:input:output:filterParameters:))

## Relationships

### Inherits From

[`UnaryLayer`](/documentation/Accelerate/BNNS/UnaryLayer)

---

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