---
title: BNNSActivationFunctionHardShrink
framework: accelerate
role: symbol
role_heading: Global Variable
path: accelerate/bnnsactivationfunctionhardshrink
---

# BNNSActivationFunctionHardShrink

An activation function that returns zero when the absolute input is less than alpha, otherwise it returns its input.

## Declaration

```swift
var BNNSActivationFunctionHardShrink: BNNSActivationFunction { get }
```

## Discussion

Discussion This constant defines an activation function that returns values using the following operation: abs(x) < abs(alpha)     0 else     x The following illustrates the output that the activation function generates from inputs in the range -10...10 and an alpha of 5:

## See Also

### Raw Values

- [init(_:)](accelerate/bnnsactivationfunction/init(_:).md)
- [init(rawValue:)](accelerate/bnnsactivationfunction/init(rawvalue:).md)
- [rawValue](accelerate/bnnsactivationfunction/rawvalue.md)
- [BNNSActivationFunctionAbs](accelerate/bnnsactivationfunctionabs.md)
- [BNNSActivationFunctionCELU](accelerate/bnnsactivationfunctioncelu.md)
- [BNNSActivationFunctionClampedLeakyRectifiedLinear](accelerate/bnnsactivationfunctionclampedleakyrectifiedlinear.md)
- [BNNSActivationFunctionELU](accelerate/bnnsactivationfunctionelu.md)
- [BNNSActivationFunctionErf](accelerate/bnnsactivationfunctionerf.md)
- [BNNSActivationFunctionGELU](accelerate/bnnsactivationfunctiongelu.md)
- [BNNSActivationFunctionGELUApproximation](accelerate/bnnsactivationfunctiongeluapproximation.md)
- [BNNSActivationFunctionGELUApproximation2](accelerate/bnnsactivationfunctiongeluapproximation2.md)
- [BNNSActivationFunctionGELUApproximationSigmoid](accelerate/bnnsactivationfunctiongeluapproximationsigmoid.md)
- [BNNSActivationFunctionGumbel](accelerate/bnnsactivationfunctiongumbel.md)
- [BNNSActivationFunctionGumbelMax](accelerate/bnnsactivationfunctiongumbelmax.md)
- [BNNSActivationFunctionHardSigmoid](accelerate/bnnsactivationfunctionhardsigmoid.md)