---
title: updateGateActivation
framework: metalperformanceshadersgraph
role: symbol
role_heading: Instance Property
path: metalperformanceshadersgraph/mpsgraphgrudescriptor/updategateactivation
---

# updateGateActivation

A parameter that defines the activation function to use with the update-gate of the GRU operation.

## Declaration

```swift
var updateGateActivation: MPSGraphRNNActivation { get set }
```

## Discussion

Discussion Default value: MPSGraphRNNActivationSigmoid.