---
title: "init(i_desc:o_desc:activation:axis_flags:)"
framework: accelerate
role: symbol
role_heading: Initializer
path: "accelerate/bnnslayerparametersactivation/init(i_desc:o_desc:activation:axis_flags:)"
---

# init(i_desc:o_desc:activation:axis_flags:)

Returns a new activation layer parameters structure from the supplied descriptors, activation function, and axis flags.

## Declaration

```swift
init(i_desc: BNNSNDArrayDescriptor, o_desc: BNNSNDArrayDescriptor, activation: BNNSActivation, axis_flags: UInt32)
```

## Parameters

- `i_desc`: The descriptor of the input.
- `o_desc`: The descriptor of the output.
- `activation`: The activation function that the layer applies to the output.
- `axis_flags`: Flags that indicate axes on which the layer applies certain activation functions.

## Discussion

Discussion important: The input dimensions must be equal to the output dimensions. For activation types other than identity, the input and output must be float.

## See Also

### Initializers

- [init()](accelerate/bnnslayerparametersactivation/init().md)