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# BNNSLossReductionFunction

Constants that describe reduction functions used by a loss layer.

```
struct BNNSLossReductionFunction
```

## Topics

### Raw Values

### Reduction Functions

[`rawValue`](/documentation/Accelerate/BNNSLossReductionFunction/rawValue)

[`init(_:)`](/documentation/Accelerate/BNNSLossReductionFunction/init(_:))

[`init(rawValue:)`](/documentation/Accelerate/BNNSLossReductionFunction/init(rawValue:))

[`BNNSLossReductionMean`](/documentation/Accelerate/BNNSLossReductionMean)

Sums the loss of all samples in the batch and divides by the number of samples.

[`BNNSLossReductionNonZeroWeightMean`](/documentation/Accelerate/BNNSLossReductionNonZeroWeightMean)

Sums the loss of all samples in the batch and divides by the number of non-zero weights.

[`BNNSLossReductionSum`](/documentation/Accelerate/BNNSLossReductionSum)

Sums the loss of all samples in the batch.

[`BNNSLossReductionWeightedMean`](/documentation/Accelerate/BNNSLossReductionWeightedMean)

Sums the loss of all samples in the batch and divides by the sum of all weights.

[`BNNSLossReductionNone`](/documentation/Accelerate/BNNSLossReductionNone)

Returns the loss without any reduction.


---

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