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# BNNS.BroadcastMatrixMultiplyLayer

A layer object that wraps a broadcast matrix multiply filter and manages its deinitialization.

```
class BroadcastMatrixMultiplyLayer
```

## Topics

### Creating a Broadcast Matrix Multiplication Layer

[`convenience init?(inputA: BNNSNDArrayDescriptor, transposed: Bool, isWeights: Bool, inputB: BNNSNDArrayDescriptor, transposed: Bool, isWeights: Bool, output: BNNSNDArrayDescriptor, alpha: Float, accumulatesToOutput: Bool, isQuadratic: Bool, filterParameters: BNNSFilterParameters?)`](/documentation/Accelerate/BNNS/BroadcastMatrixMultiplyLayer/init(inputA:transposed:isWeights:inputB:transposed:isWeights:output:alpha:accumulatesToOutput:isQuadratic:filterParameters:))

Returns a new broadcast matrix multiply layer.

### Applying a Broadcast Matrix Multiplication Layer

[`func applyBackward(batchSize: Int, inputA: BNNSNDArrayDescriptor, inputB: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, outputGradient: BNNSNDArrayDescriptor, generatingInputAGradient: BNNSNDArrayDescriptor, generatingInputBGradient: BNNSNDArrayDescriptor) throws`](/documentation/Accelerate/BNNS/BroadcastMatrixMultiplyLayer/applyBackward(batchSize:inputA:inputB:output:outputGradient:generatingInputAGradient:generatingInputBGradient:))

Applies the layer backward to generate input gradients.

### Instance Methods

[`func apply(batchSize: Int, inputA: BNNSNDArrayDescriptor, inputB: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor) throws`](/documentation/Accelerate/BNNS/BroadcastMatrixMultiplyLayer/apply(batchSize:inputA:inputB:output:))

## Relationships

### Inherits From

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

---

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