NAT: Neural Architecture Transformer for Accurate and Compact Architectures

Pytorch implementation for "NAT: Neural Architecture Transformer for Accurate and Compact Architectures".

A Simple Demo of NAT

Requirements

Python>=3.6, PyTorch==0.4.0, torchvision==0.2.1 graphviz=0.10.1 scipy=1.1.0 pygcn

Please follow the guide to install pygcn.

Datasets

We consider two benchmark classification datsets, including CIFAR-10 and ImageNet.

CIFAR-10 can be automatically downloaded by torchvision.

ImageNet needs to be manually downloaded (preferably to a SSD) following the instructions here.

Training Method

We consider to optimize two kinds of architectures, namely loose-end architectures and fully-concat architectures. More details about these two kinds of architectures can be found in ENAS and DARTS, respectively.

Train NAT for fully-concat architectures.

python train_search.py --data $DATA_DIR$ --num_nodes $NUM_NODES$ --op_type FULLY_CONCAT_PRIMITIVES

Train NAT for loose-end architectures.

python train_search.py --data $DATA_DIR$ --num_nodes $NUM_NODES$ --op_type LOOSE_END_PRIMITIVES

• DATA_DIR: path to save data.
• NUM_NODES: number of intermediate nodes in the architecture, e.g., 4 for DARTS and 5 for ENAS.

Inference Method

1. Put the input architectures in genotypes.py as follows

DARTS = Genotype(
    normal=[('sep_conv_3x3', 0, 2), ('sep_conv_3x3', 1, 2), ('sep_conv_3x3', 0, 3), ('sep_conv_3x3', 1, 3), ('sep_conv_3x3', 1, 4),
            ('skip_connect', 0, 4), ('skip_connect', 0, 5), ('dil_conv_3x3', 2, 5)], normal_concat=[2, 3, 4, 5],
    reduce=[('max_pool_3x3', 0, 2), ('max_pool_3x3', 1, 2), ('skip_connect', 2, 3), ('max_pool_3x3', 1, 3), ('max_pool_3x3', 0, 4),
            ('skip_connect', 2, 4), ('skip_connect', 2, 5), ('max_pool_3x3', 1, 5)], reduce_concat=[2, 3, 4, 5])

2. Feed an architecture into the transformer and obtain the transformed architecture

You can obtain the transformed architecture by taking an architecture as input, e.g., --arch DARTS.

python derive.py --data ./data --arch DARTS --model_path pretrained/fully_connect.pt

Figure: An example of architecture transformation.

Architecture Visualization

You can visualize both the input and the transformed architectures by

python visualize.py some_arch

where some_arch should be replaced by any architecture in genotypes.py.

Citation

If you use any part of this code in your research, please cite our paper:

@inproceedings{guo2019nat,
  title={NAT: Neural Architecture Transformer for Accurate and Compact Architectures},
  author={Guo, Yong and Zheng, Yin and Tan, Mingkui and Chen, Qi and Chen, Jian and Zhao, Peilin and Huang, Junzhou},
  booktitle={Advances in Neural Information Processing Systems},
  year={2019}
}