---
title: "init(in_size:out_size:weights:bias:activation:)"
framework: accelerate
role: symbol
role_heading: Initializer
path: "accelerate/bnnsfullyconnectedlayerparameters/init(in_size:out_size:weights:bias:activation:)"
---

# init(in_size:out_size:weights:bias:activation:)

Returns a new fully connected layer parameters structure.

## Declaration

```swift
init(in_size: Int, out_size: Int, weights: BNNSLayerData, bias: BNNSLayerData, activation: BNNSActivation)
```

## Parameters

- `in_size`: The size of the input vector.
- `out_size`: The size of the output vector.
- `weights`: Matrix coefficients, containing doc://com.apple.accelerate/documentation/Accelerate/BNNSFullyConnectedLayerParameters/in_size * doc://com.apple.accelerate/documentation/Accelerate/BNNSFullyConnectedLayerParameters/out_size values.
- `bias`: Layer bias, containing doc://com.apple.accelerate/documentation/Accelerate/BNNSFullyConnectedLayerParameters/out_size values, one for each output component.
- `activation`: The layer activation function.

## See Also

### Initializers

- [init()](accelerate/bnnsfullyconnectedlayerparameters/init().md)
- [init(in_size:out_size:weights:)](accelerate/bnnsfullyconnectedlayerparameters/init(in_size:out_size:weights:).md)