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  "identifier" : "/documentation/Accelerate/BNNS/TernaryArithmeticLayer/applyBackward(batchSize:inputA:inputB:inputC:output:outputGradient:generatingInputAGradient:generatingInputBGradient:generatingInputCGradient:)",
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# applyBackward(batchSize:inputA:inputB:inputC:output:outputGradient:generatingInputAGradient:generatingInputBGradient:generatingInputCGradient:)

Applies the layer backward to generate input gradients.

```
func applyBackward(batchSize: Int, inputA: BNNSNDArrayDescriptor, inputB: BNNSNDArrayDescriptor, inputC: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, outputGradient: BNNSNDArrayDescriptor, generatingInputAGradient inputAGradient: BNNSNDArrayDescriptor, generatingInputBGradient inputBGradient: BNNSNDArrayDescriptor, generatingInputCGradient inputCGradient: BNNSNDArrayDescriptor) throws
```

## Parameters

`batchSize`

The number of input-output pairs.

`inputA`

The descriptor of the first input..

`inputB`

The descriptor of the second input.

`inputC`

The descriptor of the third input.

`output`

The descriptor of the output.

`outputGradient`

The descriptor of the output gradient.

`inputAGradient`

The descriptor of the first input gradient.

`inputBGradient`

The descriptor of the second input gradient.

`inputCGradient`

The descriptor of the third input gradient.

---

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