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# BNNS.NormalizationLayer

A layer object that wraps a normalization filter and manages its deinitialization.

```
class NormalizationLayer
```

## Topics

### Creating a Normalization Layer

[`convenience init?(type: BNNS.NormalizationType, input: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, beta: BNNSNDArrayDescriptor, gamma: BNNSNDArrayDescriptor, momentum: Float, epsilon: Float, activation: BNNS.ActivationFunction, filterParameters: BNNSFilterParameters?)`](/documentation/Accelerate/BNNS/NormalizationLayer/init(type:input:output:beta:gamma:momentum:epsilon:activation:filterParameters:))

Returns a new normalization layer.

### Specifying a Normalization Type

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

Constants that describe normalization types.

### Applying a Normalization Layer

[`func apply(batchSize: Int, input: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, for: BNNS.LearningPhase) throws`](/documentation/Accelerate/BNNS/NormalizationLayer/apply(batchSize:input:output:for:))

Applies the layer to a set of input objects, writing the result to a set of output objects.

[`func applyBackward(batchSize: Int, input: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, outputGradient: BNNSNDArrayDescriptor, generatingInputGradient: BNNSNDArrayDescriptor, generatingBetaGradient: BNNSNDArrayDescriptor?, generatingGammaGradient: BNNSNDArrayDescriptor?) throws`](/documentation/Accelerate/BNNS/NormalizationLayer/applyBackward(batchSize:input:output:outputGradient:generatingInputGradient:generatingBetaGradient:generatingGammaGradient:))

Applies the layer backward to generate input gradients.

### Specifying the Learning Phase

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

Constants that describe the learning phase of a normalization operation.

## Relationships

### Inherits From

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

---

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