# BNNS.ActivationFunction.leakyRectifiedLinear(alpha:) An activation function that returns its input when that is greater than or equal to zero, otherwise it returns its input multiplied by a specified value. ``` case leakyRectifiedLinear(alpha: Float) ``` ## Discussion This constant defines an activation function that returns values using the following operation: ```c alpha*x if x<0, and x if x>=0 ``` Use `alpha` to specify the multiplier for values less than zero range: ```swift var activation = BNNSActivation(function: .leakyRectifiedLinear, alpha: 0.25) ``` The following illustrates the output that the activation function generates from inputs in the range `-10...10`:  --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)