---
title: iw_desc
framework: accelerate
role: symbol
role_heading: Instance Property
path: accelerate/bnnslstmgatedescriptor/iw_desc
---

# iw_desc

The descriptor of the input weights.

## Declaration

```swift
var iw_desc: (BNNSNDArrayDescriptor, BNNSNDArrayDescriptor)
```

## Discussion

Discussion Weights are ordered as [num_layers][num_directions][hidden_size][input_size] (C style multi array notation). iw_desc is duplicated for the case where num_layers > 1 && input_size != hidden_size.

## See Also

### Instance Properties

- [hw_desc](accelerate/bnnslstmgatedescriptor/hw_desc.md)
- [cw_desc](accelerate/bnnslstmgatedescriptor/cw_desc.md)
- [b_desc](accelerate/bnnslstmgatedescriptor/b_desc.md)
- [activation](accelerate/bnnslstmgatedescriptor/activation.md)