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# init(target_desc:weights:bias:)

Returns a new multihead attention projection parameters structure from the specified parameters.

```
init(target_desc: BNNSNDArrayDescriptor, weights: BNNSNDArrayDescriptor, bias: BNNSNDArrayDescriptor)
```

## Parameters

`target_desc`

The descriptor—which is either an input query, key, or value, or an output—of the main target of the operation.

`weights`

The descriptor of the initial projection’s weights.

`bias`

The descriptor of the initial projection’s bias.

---

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