---
title: input_gate
framework: accelerate
role: symbol
role_heading: Instance Property
path: accelerate/bnnslayerparameterslstm/input_gate
---

# input_gate

The descriptor of the input gate, which uses default sigmoid activation.

## Declaration

```swift
var input_gate: BNNSLSTMGateDescriptor
```

## Discussion

Discussion Use C style multidimensional array notation to order the memory pointers as [ num_layers ][num_directions][ hidden_size ][ input_size / hidden_size ]. If lstm_flags includes BNNSLayerFlagsLSTMBidirectional, BNNS defines num_directions as 2, or otherwise 1.

## See Also

### Instance Properties

- [input_size](accelerate/bnnslayerparameterslstm/input_size.md)
- [hidden_size](accelerate/bnnslayerparameterslstm/hidden_size.md)
- [batch_size](accelerate/bnnslayerparameterslstm/batch_size.md)
- [num_layers](accelerate/bnnslayerparameterslstm/num_layers.md)
- [seq_len](accelerate/bnnslayerparameterslstm/seq_len.md)
- [dropout](accelerate/bnnslayerparameterslstm/dropout.md)
- [lstm_flags](accelerate/bnnslayerparameterslstm/lstm_flags.md)
- [sequence_descriptor](accelerate/bnnslayerparameterslstm/sequence_descriptor.md)
- [input_descriptor](accelerate/bnnslayerparameterslstm/input_descriptor.md)
- [output_descriptor](accelerate/bnnslayerparameterslstm/output_descriptor.md)
- [forget_gate](accelerate/bnnslayerparameterslstm/forget_gate.md)
- [candidate_gate](accelerate/bnnslayerparameterslstm/candidate_gate.md)
- [output_gate](accelerate/bnnslayerparameterslstm/output_gate.md)
- [hidden_activation](accelerate/bnnslayerparameterslstm/hidden_activation.md)