README.md

x-transformers (wip)

X stands for experimental

A simple full-attention transformer, but also complete with a set of promising experimental features from various papers.

Install

$ pip install x-transformers

Usage

import torch
from x_transformers import XTransformer

model = XTransformer(
    num_tokens = 256,
    dim = 512,
    depth = 6,
    heads = 8,
    max_seq_len = 1024
)
src = torch.randint(0, 256, (1, 1024))
tgt = torch.randint(0, 256, (1, 1024))
model(src, tgt) # (1, 1024, 512)

Citations

@inproceedings{kitaev2020reformer,
    title       = {Reformer: The Efficient Transformer},
    author      = {Nikita Kitaev and Lukasz Kaiser and Anselm Levskaya},
    booktitle   = {International Conference on Learning Representations},
    year        = {2020},
    url         = {https://openreview.net/forum?id=rkgNKkHtvB}
}

@article{DBLP:journals/corr/abs-1907-01470,
    author    = {Sainbayar Sukhbaatar and
               Edouard Grave and
               Guillaume Lample and
               Herv{\'{e}} J{\'{e}}gou and
               Armand Joulin},
    title     = {Augmenting Self-attention with Persistent Memory},
    journal   = {CoRR},
    volume    = {abs/1907.01470},
    year      = {2019},
    url       = {http://arxiv.org/abs/1907.01470}
}

@article{1910.05895,
    author  = {Toan Q. Nguyen and Julian Salazar},
    title   = {Transformers without Tears: Improving the Normalization of Self-Attention},
    year    = {2019},
    eprint  = {arXiv:1910.05895},
    doi     = {10.5281/zenodo.3525484},
}

@misc{shazeer2020glu,
    title   = {GLU Variants Improve Transformer},
    author  = {Noam Shazeer},
    year    = {2020},
    url     = {https://arxiv.org/abs/2002.05202}    
}

@misc{bachlechner2020rezero,
    title   = {ReZero is All You Need: Fast Convergence at Large Depth},
    author  = {Thomas Bachlechner and Bodhisattwa Prasad Majumder and Huanru Henry Mao and Garrison W. Cottrell and Julian McAuley},
    year    = {2020},
    url     = {https://arxiv.org/abs/2003.04887}
}

@misc{bhojanapalli2020lowrank,
    title   = {Low-Rank Bottleneck in Multi-head Attention Models},
    author  = {Srinadh Bhojanapalli and Chulhee Yun and Ankit Singh Rawat and Sashank J. Reddi and Sanjiv Kumar},
    year    = {2020},
    eprint  = {2002.07028}
}

@misc{burtsev2020memory,
    title   = {Memory Transformer}, 
    author  = {Mikhail S. Burtsev and Grigory V. Sapunov},
    year        = {2020},
    eprint  = {2006.11527},
    archivePrefix = {arXiv},
    primaryClass = {cs.CL}
}

@misc{correia2019adaptively,
    title   = {Adaptively Sparse Transformers}, 
    author  = {Gonçalo M. Correia and Vlad Niculae and André F. T. Martins},
    year        = {2019},
    eprint  = {1909.00015},
    archivePrefix = {arXiv},
    primaryClass = {cs.CL}
}

@misc{shazeer2020talkingheads,
    title   = {Talking-Heads Attention}, 
    author  = {Noam Shazeer and Zhenzhong Lan and Youlong Cheng and Nan Ding and Le Hou},
    year        = {2020},
    eprint  = {2003.02436},
    archivePrefix = {arXiv},
    primaryClass = {cs.LG}
}

@misc{press2020improving,
    title   = {Improving Transformer Models by Reordering their Sublayers}, 
    author  = {Ofir Press and Noah A. Smith and Omer Levy},
    year    = {2020},
    eprint  = {1911.03864},
    archivePrefix = {arXiv},
    primaryClass = {cs.CL}
}

@misc{lu2019understanding,
    title   = {Understanding and Improving Transformer From a Multi-Particle Dynamic System Point of View}, 
    author  = {Yiping Lu and Zhuohan Li and Di He and Zhiqing Sun and Bin Dong and Tao Qin and Liwei Wang and Tie-Yan Liu},
    year    = {2019},
    eprint  = {1906.02762},
    archivePrefix = {arXiv},
    primaryClass = {cs.LG}
}

@misc{zhang2020selfattention,
    title   = {When Can Self-Attention Be Replaced by Feed Forward Layers?}, 
    author  = {Shucong Zhang and Erfan Loweimi and Peter Bell and Steve Renals},
    year    = {2020},
    eprint  = {2005.13895},
    archivePrefix = {arXiv},
    primaryClass = {eess.AS}
}

@misc{ke2020rethinking,
    title     = {Rethinking Positional Encoding in Language Pre-training},
    author    = {Guolin Ke and Di He and Tie-Yan Liu},
    year      = {2020},
    eprint    = {2006.15595},
    archivePrefix = {arXiv},
    primaryClass = {cs.CL}
}

@misc{dai2020funneltransformer,
    title   = {Funnel-Transformer: Filtering out Sequential Redundancy for Efficient Language Processing},
    author  = {Zihang Dai and Guokun Lai and Yiming Yang and Quoc V. Le},
    year    = {2020},
    eprint  = {2006.03236},
    archivePrefix = {arXiv},
    primaryClass = {cs.LG}
}