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# Byte-compiled / optimized / DLL files
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__pycache__/
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*.py[cod]
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*$py.class
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# C extensions
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*.so
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# Distribution / packaging
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.Python
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build/
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develop-eggs/
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dist/
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downloads/
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eggs/
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.eggs/
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lib/
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lib64/
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parts/
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sdist/
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var/
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wheels/
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*.egg-info/
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.installed.cfg
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*.egg
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MANIFEST
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# PyInstaller
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# Usually these files are written by a python script from a template
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# before PyInstaller builds the exe, so as to inject date/other infos into it.
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*.manifest
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*.spec
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# Installer logs
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pip-log.txt
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pip-delete-this-directory.txt
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# Unit test / coverage reports
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htmlcov/
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.tox/
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.coverage
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.coverage.*
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.cache
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nosetests.xml
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coverage.xml
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*.cover
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.hypothesis/
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.pytest_cache/
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# Translations
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*.mo
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*.pot
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# Django stuff:
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*.log
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local_settings.py
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db.sqlite3
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# Flask stuff:
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instance/
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.webassets-cache
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# Scrapy stuff:
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.scrapy
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# Sphinx documentation
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docs/_build/
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# PyBuilder
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target/
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# Jupyter Notebook
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.ipynb_checkpoints
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# pyenv
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.python-version
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# celery beat schedule file
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celerybeat-schedule
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# SageMath parsed files
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*.sage.py
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# Environments
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.env
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.venv
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env/
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venv/
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ENV/
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env.bak/
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venv.bak/
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# Spyder project settings
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.spyderproject
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.spyproject
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# Rope project settings
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.ropeproject
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# mkdocs documentation
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/site
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# mypy
|
||||
.mypy_cache/
|
||||
# VSCode
|
||||
.vscode
|
481
bert_model.py
Normal file
481
bert_model.py
Normal file
@ -0,0 +1,481 @@
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"""
|
||||
A PyTorch implementation of Google's BERT Model.
|
||||
|
||||
From "BERT: Pre-training of Deep Bidirectional Transformers for Language Understanding"
|
||||
By Jacob Devlin, Ming-Wei Chang, Kenton Lee, Kristina Toutanova
|
||||
Link: http://arxiv.org/abs/1810.04805
|
||||
|
||||
Adapted from HuggingFace's OpenAI PyTorch code and its adaptation by AllenNLP.
|
||||
"""
|
||||
|
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# pylint: disable=invalid-name,arguments-differ
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||||
from typing import NamedTuple, List
|
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import copy
|
||||
import io
|
||||
import json
|
||||
import logging
|
||||
import math
|
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import pathlib
|
||||
import re
|
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import tarfile
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|
||||
import numpy as np
|
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import torch
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from torch.nn import Parameter
|
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|
||||
# pylint: disable=line-too-long
|
||||
_PARAMETER_NAMES = ["model/we:0",
|
||||
"model/h0/attn/c_attn/w:0", "model/h0/attn/c_attn/b:0", "model/h0/attn/c_proj/w:0",
|
||||
"model/h0/attn/c_proj/b:0", "model/h0/ln_1/g:0", "model/h0/ln_1/b:0", "model/h0/mlp/c_fc/w:0",
|
||||
"model/h0/mlp/c_fc/b:0", "model/h0/mlp/c_proj/w:0", "model/h0/mlp/c_proj/b:0", "model/h0/ln_2/g:0",
|
||||
"model/h0/ln_2/b:0", "model/h1/attn/c_attn/w:0", "model/h1/attn/c_attn/b:0", "model/h1/attn/c_proj/w:0",
|
||||
"model/h1/attn/c_proj/b:0", "model/h1/ln_1/g:0", "model/h1/ln_1/b:0", "model/h1/mlp/c_fc/w:0",
|
||||
"model/h1/mlp/c_fc/b:0", "model/h1/mlp/c_proj/w:0", "model/h1/mlp/c_proj/b:0", "model/h1/ln_2/g:0",
|
||||
"model/h1/ln_2/b:0", "model/h2/attn/c_attn/w:0", "model/h2/attn/c_attn/b:0", "model/h2/attn/c_proj/w:0",
|
||||
"model/h2/attn/c_proj/b:0", "model/h2/ln_1/g:0", "model/h2/ln_1/b:0", "model/h2/mlp/c_fc/w:0",
|
||||
"model/h2/mlp/c_fc/b:0", "model/h2/mlp/c_proj/w:0", "model/h2/mlp/c_proj/b:0", "model/h2/ln_2/g:0",
|
||||
"model/h2/ln_2/b:0", "model/h3/attn/c_attn/w:0", "model/h3/attn/c_attn/b:0", "model/h3/attn/c_proj/w:0",
|
||||
"model/h3/attn/c_proj/b:0", "model/h3/ln_1/g:0", "model/h3/ln_1/b:0", "model/h3/mlp/c_fc/w:0",
|
||||
"model/h3/mlp/c_fc/b:0", "model/h3/mlp/c_proj/w:0", "model/h3/mlp/c_proj/b:0", "model/h3/ln_2/g:0",
|
||||
"model/h3/ln_2/b:0", "model/h4/attn/c_attn/w:0", "model/h4/attn/c_attn/b:0", "model/h4/attn/c_proj/w:0",
|
||||
"model/h4/attn/c_proj/b:0", "model/h4/ln_1/g:0", "model/h4/ln_1/b:0", "model/h4/mlp/c_fc/w:0",
|
||||
"model/h4/mlp/c_fc/b:0", "model/h4/mlp/c_proj/w:0", "model/h4/mlp/c_proj/b:0", "model/h4/ln_2/g:0",
|
||||
"model/h4/ln_2/b:0", "model/h5/attn/c_attn/w:0", "model/h5/attn/c_attn/b:0", "model/h5/attn/c_proj/w:0",
|
||||
"model/h5/attn/c_proj/b:0", "model/h5/ln_1/g:0", "model/h5/ln_1/b:0", "model/h5/mlp/c_fc/w:0",
|
||||
"model/h5/mlp/c_fc/b:0", "model/h5/mlp/c_proj/w:0", "model/h5/mlp/c_proj/b:0", "model/h5/ln_2/g:0",
|
||||
"model/h5/ln_2/b:0", "model/h6/attn/c_attn/w:0", "model/h6/attn/c_attn/b:0", "model/h6/attn/c_proj/w:0",
|
||||
"model/h6/attn/c_proj/b:0", "model/h6/ln_1/g:0", "model/h6/ln_1/b:0", "model/h6/mlp/c_fc/w:0",
|
||||
"model/h6/mlp/c_fc/b:0", "model/h6/mlp/c_proj/w:0", "model/h6/mlp/c_proj/b:0", "model/h6/ln_2/g:0",
|
||||
"model/h6/ln_2/b:0", "model/h7/attn/c_attn/w:0", "model/h7/attn/c_attn/b:0", "model/h7/attn/c_proj/w:0",
|
||||
"model/h7/attn/c_proj/b:0", "model/h7/ln_1/g:0", "model/h7/ln_1/b:0", "model/h7/mlp/c_fc/w:0",
|
||||
"model/h7/mlp/c_fc/b:0", "model/h7/mlp/c_proj/w:0", "model/h7/mlp/c_proj/b:0", "model/h7/ln_2/g:0",
|
||||
"model/h7/ln_2/b:0", "model/h8/attn/c_attn/w:0", "model/h8/attn/c_attn/b:0", "model/h8/attn/c_proj/w:0",
|
||||
"model/h8/attn/c_proj/b:0", "model/h8/ln_1/g:0", "model/h8/ln_1/b:0", "model/h8/mlp/c_fc/w:0",
|
||||
"model/h8/mlp/c_fc/b:0", "model/h8/mlp/c_proj/w:0", "model/h8/mlp/c_proj/b:0", "model/h8/ln_2/g:0",
|
||||
"model/h8/ln_2/b:0", "model/h9/attn/c_attn/w:0", "model/h9/attn/c_attn/b:0", "model/h9/attn/c_proj/w:0",
|
||||
"model/h9/attn/c_proj/b:0", "model/h9/ln_1/g:0", "model/h9/ln_1/b:0", "model/h9/mlp/c_fc/w:0",
|
||||
"model/h9/mlp/c_fc/b:0", "model/h9/mlp/c_proj/w:0", "model/h9/mlp/c_proj/b:0", "model/h9/ln_2/g:0",
|
||||
"model/h9/ln_2/b:0", "model/h10/attn/c_attn/w:0", "model/h10/attn/c_attn/b:0", "model/h10/attn/c_proj/w:0",
|
||||
"model/h10/attn/c_proj/b:0", "model/h10/ln_1/g:0", "model/h10/ln_1/b:0", "model/h10/mlp/c_fc/w:0",
|
||||
"model/h10/mlp/c_fc/b:0", "model/h10/mlp/c_proj/w:0", "model/h10/mlp/c_proj/b:0", "model/h10/ln_2/g:0",
|
||||
"model/h10/ln_2/b:0", "model/h11/attn/c_attn/w:0", "model/h11/attn/c_attn/b:0", "model/h11/attn/c_proj/w:0",
|
||||
"model/h11/attn/c_proj/b:0", "model/h11/ln_1/g:0", "model/h11/ln_1/b:0", "model/h11/mlp/c_fc/w:0",
|
||||
"model/h11/mlp/c_fc/b:0", "model/h11/mlp/c_proj/w:0", "model/h11/mlp/c_proj/b:0", "model/h11/ln_2/g:0",
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"model/h11/ln_2/b:0", "model/clf/w:0", "model/clf/b:0"]
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# pylint: enable=line-too-long
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def gelu(x: torch.Tensor) -> torch.Tensor:
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return 0.5 * x * (1 + torch.tanh(math.sqrt(2 / math.pi) * (x + 0.044715 * torch.pow(x, 3))))
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class BERTConfig(NamedTuple):
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"""
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BERT's hyper-parameters
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"""
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embedding_dim: int = 768
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num_heads: int = 12
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dropout: float = 0.1
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class LayerNorm(torch.nn.Module):
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"""
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A layernorm module in the Tensorflow style (with the epsilon inside the square root).
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"""
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def __init__(self, n_state, e=1e-5):
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super().__init__()
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self.g = torch.nn.Parameter(torch.ones(n_state))
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self.b = torch.nn.Parameter(torch.zeros(n_state))
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self.e = e
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def forward(self, x):
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u = x.mean(-1, keepdim=True)
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s = (x - u).pow(2).mean(-1, keepdim=True)
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x = (x - u) / torch.sqrt(s + self.e)
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return self.g * x + self.b
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class Conv1D(torch.nn.Module):
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"""
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A batched linear layer using torch.addmm
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"""
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def __init__(self, nf: int, rf: int, nx: int) -> None:
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super().__init__()
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self.rf = rf
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self.nf = nf
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w = torch.empty(nx, nf)
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torch.nn.init.normal_(w, std=0.02)
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self.w = Parameter(w)
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self.b = Parameter(torch.zeros(nf))
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def forward(self, x: torch.Tensor) -> torch.Tensor:
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size_out = x.size()[:-1] + (self.nf,)
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x = torch.addmm(self.b, x.view(-1, x.size(-1)), self.w)
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x = x.view(*size_out)
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return x
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class Attention(torch.nn.Module):
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"""
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A self-attention layer comprising a sequence of:
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- a linear layer: instance of the `Conv1D` class,
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- spliting the inputs in key, value, query tensors (x.split),
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- reshaping key, value, query tensors according to the number of head (self.split_heads)
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- appying self attention (self._attn)
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- merging back the heads results (self.merge_heads)
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- a linear layer: instance of the `Conv1D` class,
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- a dropout layer: instance of `torch.nn.Dropout` class.
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See above for the details of Conv1D.
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"""
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def __init__(self,
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nx: int,
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n_ctx: int,
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config: BERTConfig,
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scale: bool = False) -> None:
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super().__init__()
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n_state = nx # in Attention: n_state=768 (nx=n_embd)
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# [switch nx => n_state from Block to Attention to keep identical to TF implem]
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assert n_state % config.num_heads == 0
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self.register_buffer('b', torch.tril(torch.ones(n_ctx, n_ctx)).view(1, 1, n_ctx, n_ctx))
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self.n_head = config.num_heads
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self.split_size = n_state
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self.scale = scale
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self.c_attn = Conv1D(n_state * 3, 1, nx)
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self.c_proj = Conv1D(n_state, 1, nx)
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self.attn_dropout = torch.nn.Dropout(config.dropout)
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self.resid_dropout = torch.nn.Dropout(config.dropout)
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def _attn(self, q: torch.Tensor, k: torch.Tensor, v: torch.Tensor) -> torch.Tensor:
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w = torch.matmul(q, k)
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if self.scale:
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w = w / math.sqrt(v.size(-1))
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w = w * self.b + -1e9 * (1 - self.b) # TF implem method: mask_attn_weights
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w = torch.nn.Softmax(dim=-1)(w)
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w = self.attn_dropout(w)
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return torch.matmul(w, v)
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def merge_heads(self, x: torch.Tensor):
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# pylint: disable=no-self-use
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x = x.permute(0, 2, 1, 3).contiguous()
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new_x_shape = x.size()[:-2] + (x.size(-2) * x.size(-1),)
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return x.view(*new_x_shape) # in Tensorflow implem: fct merge_states
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def split_heads(self, x: torch.Tensor, k: bool = False):
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new_x_shape = x.size()[:-1] + (self.n_head, x.size(-1) // self.n_head)
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x = x.view(*new_x_shape) # in Tensorflow implem: fct split_states
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if k:
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return x.permute(0, 2, 3, 1)
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else:
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return x.permute(0, 2, 1, 3)
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|
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def forward(self, x: torch.Tensor) -> torch.Tensor:
|
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x = self.c_attn(x)
|
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query, key, value = x.split(self.split_size, dim=2)
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query = self.split_heads(query)
|
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key = self.split_heads(key, k=True)
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||||
value = self.split_heads(value)
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||||
a = self._attn(query, key, value)
|
||||
a = self.merge_heads(a)
|
||||
a = self.c_proj(a)
|
||||
a = self.resid_dropout(a)
|
||||
return a
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||||
|
||||
|
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class MLP(torch.nn.Module):
|
||||
"""
|
||||
A multi-layer perceptron layer comprising a sequence of:
|
||||
- a linear layer: instance of the `Conv1D` class,
|
||||
- an activation function: the `gelu` function,
|
||||
- another linear layer: instance of the `Conv1D` class,
|
||||
- a dropout layer: instance of `torch.nn.Dropout` class.
|
||||
|
||||
See above for the details of Conv1D and the gelu function.
|
||||
"""
|
||||
def __init__(self, n_state: int, config: BERTConfig) -> None: # in MLP: n_state=3072 (4 * n_embd)
|
||||
super().__init__()
|
||||
self.c_fc = Conv1D(n_state, 1, config.embedding_dim)
|
||||
self.c_proj = Conv1D(config.embedding_dim, 1, n_state)
|
||||
self.act = gelu
|
||||
self.dropout = torch.nn.Dropout(config.dropout)
|
||||
|
||||
def forward(self, x: torch.Tensor) -> torch.Tensor:
|
||||
h = self.act(self.c_fc(x))
|
||||
h2 = self.c_proj(h)
|
||||
return self.dropout(h2)
|
||||
|
||||
|
||||
class Block(torch.nn.Module):
|
||||
"""
|
||||
A Transformer Block comprising a sequence of:
|
||||
- a self-attention layer: instance of the `Attention` class,
|
||||
- a Layer Normalization layer: instance of the `LayerNorm` class,
|
||||
- a Multi-layer perceptron layer: instance of the `MLP` class,
|
||||
- another Layer Normalization layer: instance of the `LayerNorm` class.
|
||||
|
||||
See above for the details of these classes.
|
||||
"""
|
||||
def __init__(self,
|
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n_ctx: int,
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||||
config: BERTConfig,
|
||||
scale: bool = False) -> None:
|
||||
super().__init__()
|
||||
nx = config.embedding_dim
|
||||
self.attn = Attention(nx, n_ctx, config, scale)
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||||
self.ln_1 = LayerNorm(nx)
|
||||
self.mlp = MLP(4 * nx, config)
|
||||
self.ln_2 = LayerNorm(nx)
|
||||
|
||||
def forward(self, x: torch.Tensor) -> torch.Tensor:
|
||||
a = self.attn(x)
|
||||
n = self.ln_1(x + a)
|
||||
m = self.mlp(n)
|
||||
h = self.ln_2(n + m)
|
||||
return h
|
||||
|
||||
class BERT(torch.nn.Module):
|
||||
"""
|
||||
Google's BERT Model.
|
||||
Default parameters are the ones for Google's pretrained model.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
vocab_size: ``int`` (optional, default: 40478)
|
||||
The size of the vocabulary (number of byte pair embeddings)
|
||||
excluding the n_special embeddings (if any), and the positional embeddings.
|
||||
n_ctx: ``int`` (optional, default: 512)
|
||||
The number of positional encodings to use for evaluation.
|
||||
embedding_dim: ``int`` (optional, default: 768)
|
||||
The dimension of the output embeddings.
|
||||
num_heads: ``int`` (optional, default: 12)
|
||||
How many "heads" the attention has.
|
||||
num_layers: ``int`` (optional, default: 12)
|
||||
How many layers of "blocks" the transformer has.
|
||||
dropout_probability: ``float`` (optional, default: 0.1)
|
||||
Dropout for all layers.
|
||||
model_path: ``str`` (optional, default: ``None``)
|
||||
A tar.gz file containing serialized model weights. If supplied,
|
||||
the weights will be loaded from that file.
|
||||
requires_grad: ``bool`` (optional, default: ``False``)
|
||||
If true, the transformer will be fine-tuneable.
|
||||
n_special: ``int`` (optional, default: ``-1``)
|
||||
The number of special tokens added to the byte pair vocabulary
|
||||
"""
|
||||
def __init__(self,
|
||||
vocab_size: int = 40478,
|
||||
n_ctx: int = 512,
|
||||
embedding_dim: int = 768,
|
||||
num_heads: int = 12,
|
||||
num_layers: int = 12,
|
||||
dropout_probability: float = 0.1,
|
||||
model_path: str = None,
|
||||
requires_grad: bool = False,
|
||||
n_special: int = -1) -> None:
|
||||
super().__init__()
|
||||
|
||||
config = BERTConfig(
|
||||
embedding_dim,
|
||||
num_heads,
|
||||
embedding_dropout_probability,
|
||||
attention_dropout_probability,
|
||||
residual_dropout_probability,
|
||||
activation_function,
|
||||
)
|
||||
|
||||
# the embedding size is vocab_size + n_special embeddings + n_ctx
|
||||
embedding_size = vocab_size + max(n_special, 0) + n_ctx
|
||||
self.vocab_size = embedding_size
|
||||
self.n_ctx = n_ctx
|
||||
self.n_special = n_special
|
||||
|
||||
self.num_output_layers = 1 + num_layers
|
||||
|
||||
self.embed = torch.nn.Embedding(embedding_size, embedding_dim)
|
||||
self.drop = torch.nn.Dropout(embedding_dropout_probability)
|
||||
|
||||
block = Block(n_ctx, config, scale=True)
|
||||
self.h = torch.nn.ModuleList([copy.deepcopy(block) for _ in range(num_layers)])
|
||||
self.decoder = torch.nn.Linear(embedding_dim, embedding_size, bias=False)
|
||||
self.decoder.weight = self.embed.weight # Tied weights
|
||||
# To reproduce the noise_shape parameter of TF implementation
|
||||
|
||||
torch.nn.init.normal_(self.embed.weight, std=0.02)
|
||||
|
||||
for parameter in self.parameters():
|
||||
parameter.requires_grad = requires_grad
|
||||
|
||||
if model_path:
|
||||
self.load_weights(model_path, n_special=n_special, n_ctx=n_ctx)
|
||||
|
||||
def forward(self, x: torch.Tensor) -> List[torch.Tensor]:
|
||||
#x = x.view(-1, x.size(2), x.size(3))
|
||||
|
||||
# x is (batch_size, sequence_length) tensor of byte-pair ids
|
||||
|
||||
# e is (batch_size, sequence_length, 2, embedding_dim) tensor of embeddings
|
||||
e = self.embed(x)
|
||||
|
||||
# h is (batch_size, sequence_length, embedding_dim)
|
||||
h = e.sum(dim=2)
|
||||
|
||||
all_layers = [h]
|
||||
for block in self.h:
|
||||
h = block(h)
|
||||
all_layers.append(h)
|
||||
|
||||
# result is list of (batch_size, sequence_length, embedding_dim)
|
||||
return all_layers
|
||||
|
||||
def load_weights(self,
|
||||
bert_model_path: str,
|
||||
n_ctx: int = -1,
|
||||
n_special: int = -1,
|
||||
n_transfer: int = 12,
|
||||
n_embd: int = 768,
|
||||
names: List[str] = _PARAMETER_NAMES) -> None:
|
||||
# pylint: disable=dangerous-default-value
|
||||
|
||||
logger.info(f"loading weights from {bert_model_path}")
|
||||
# if `file_path` is a URL, redirect to the cache
|
||||
|
||||
with tarfile.open(bert_model_path) as tmp:
|
||||
num_params_files = len([member for member in tmp.getmembers() if member.name.endswith('.npy')])
|
||||
shapesfile = tmp.extractfile('model/params_shapes.json')
|
||||
if shapesfile:
|
||||
shapes = json.loads(shapesfile.read())
|
||||
else:
|
||||
raise ConfigurationError("unable to find model/params_shapes.json in the archive")
|
||||
|
||||
# numpy can't read from a tarfile directly, so we need a workaround
|
||||
# https://github.com/numpy/numpy/issues/7989#issuecomment-341656702
|
||||
init_params: List[np.ndarray] = []
|
||||
for n in range(num_params_files):
|
||||
array_file = io.BytesIO()
|
||||
array_file.write(tmp.extractfile(f'model/params_{n}.npy').read())
|
||||
array_file.seek(0)
|
||||
# each np.load is a (11653478,) numpy array
|
||||
init_params.append(np.load(array_file))
|
||||
|
||||
# init_params is a list of 10 arrays of size (11653578,)
|
||||
# shapes are [[512, 768], [40478, 768], [1, 768, 2304], [2304], ... # 146 elts
|
||||
# products are [512 * 768, 40478 * 768, ...]
|
||||
# offsets is [512 * 768, 512 * 768 + 40478 * 768, ...]
|
||||
offsets = np.cumsum([np.prod(shape) for shape in shapes])
|
||||
|
||||
# split into the 146 subarrays corresponding to shapes
|
||||
init_params = np.split(np.concatenate(init_params, 0), offsets)[:-1]
|
||||
|
||||
# reshape
|
||||
init_params = [param.reshape(shape) for param, shape in zip(init_params, shapes)]
|
||||
|
||||
# truncate if necessary
|
||||
if n_ctx > 0:
|
||||
# positional embeddings?
|
||||
# init_params[0] is (512, 768) = (max_chars, embedding_dim)
|
||||
init_params[0] = init_params[0][:n_ctx]
|
||||
|
||||
# combine init_params[1] and init_params[0]
|
||||
if n_special > 0:
|
||||
# init_params[1] is (40478, 768)
|
||||
# special is (n_special, 768)
|
||||
# init_params[0] is (512, 768)
|
||||
# result is (40990 + n_special, 768)
|
||||
init_params[0] = np.concatenate(
|
||||
[init_params[1],
|
||||
(np.random.randn(n_special, n_embd) * 0.02).astype(np.float32),
|
||||
init_params[0]],
|
||||
0
|
||||
)
|
||||
else:
|
||||
# result is (40990, 768)
|
||||
init_params[0] = np.concatenate([init_params[1], init_params[0]], 0)
|
||||
del init_params[1]
|
||||
|
||||
# number of dimensions to transfer, 12 per layer, plus one extra
|
||||
if n_transfer == -1:
|
||||
n_transfer = 0
|
||||
else:
|
||||
n_transfer = 1 + n_transfer * 12
|
||||
|
||||
# squeeze?
|
||||
init_params = [arr.squeeze() for arr in init_params]
|
||||
|
||||
# embedding.weight is (vocab_size, embedding_dim)
|
||||
# make sure init_params[0] has the same shape
|
||||
try:
|
||||
assert self.embed.weight.shape == init_params[0].shape
|
||||
except AssertionError as e:
|
||||
e.args += (self.embed.weight.shape, init_params[0].shape)
|
||||
raise
|
||||
|
||||
# and then assign it
|
||||
self.embed.weight.data = torch.from_numpy(init_params[0])
|
||||
self.decoder.weight = self.embed.weight
|
||||
|
||||
# for each (name, array) pair to transfer over
|
||||
for name, ip in zip(names[1:n_transfer], init_params[1:n_transfer]):
|
||||
# "model/h0/attn/c_attn/w:0"
|
||||
name = name[6:] # "h0/attn/c_attn/w:0"
|
||||
assert name[-2:] == ":0"
|
||||
name = name[:-2] # "h0/attn/c_attn/w"
|
||||
name_parts = name.split('/') # ['h0', 'attn', 'c_attn', 'w']
|
||||
|
||||
pointer = self
|
||||
for m_name in name_parts:
|
||||
if re.fullmatch(r'[A-Za-z]+\d+', m_name):
|
||||
l = re.split(r'(\d+)', m_name) # ['h', '0', '']
|
||||
else:
|
||||
l = [m_name] # ['attn']
|
||||
pointer = getattr(pointer, l[0])
|
||||
if len(l) >= 2:
|
||||
num = int(l[1])
|
||||
pointer = pointer[num]
|
||||
try:
|
||||
assert pointer.shape == ip.shape
|
||||
except AssertionError as e:
|
||||
e.args += (pointer.shape, ip.shape)
|
||||
raise
|
||||
|
||||
pointer.data = torch.from_numpy(ip) # pylint: disable=attribute-defined-outside-init
|
||||
|
||||
def dump_weights(self,
|
||||
output_dir: str,
|
||||
num_pieces: int = 10) -> None:
|
||||
output_path = pathlib.Path(output_dir) / 'model'
|
||||
output_path.mkdir(exist_ok=True, parents=True) # pylint: disable=no-member
|
||||
|
||||
named_parameters = list(self.named_parameters())
|
||||
|
||||
# embedding weights get special treatment
|
||||
_, array = named_parameters[0]
|
||||
num_bpe = self.vocab_size - self.n_ctx
|
||||
byte_pair_embeddings = array[:num_bpe]
|
||||
positional_embeddings = array[num_bpe:]
|
||||
|
||||
arrays = [positional_embeddings.numpy().ravel(), byte_pair_embeddings.numpy().ravel()]
|
||||
shapes = [positional_embeddings.shape, byte_pair_embeddings.shape]
|
||||
names = ["model/we:0"]
|
||||
|
||||
for param_name, tensor in named_parameters[1:]:
|
||||
param_name = f'h{param_name}' # 'h0.attn.c_attn.w'
|
||||
parts = param_name.split(".") # ['h0', 'attn', 'c_attn', 'w']
|
||||
name = "model/" + '/'.join(parts) + ':0' # 'model/h0/attn/c_attn/w:0'
|
||||
array = tensor.numpy().ravel()
|
||||
|
||||
arrays.append(array)
|
||||
shapes.append(list(tensor.shape))
|
||||
names.append(name)
|
||||
|
||||
# write out the arrays
|
||||
big_array = np.concatenate(arrays)
|
||||
total_size = len(big_array)
|
||||
batch_size = math.ceil(total_size / num_pieces)
|
||||
|
||||
for i in range(num_pieces):
|
||||
filename = output_path / f"params_{i}.npy"
|
||||
start = i * batch_size
|
||||
end = start + batch_size
|
||||
subarray = big_array[start:end]
|
||||
|
||||
np.save(filename, subarray)
|
||||
|
||||
# write out the shapes
|
||||
with open(output_path / 'params_shapes.json', 'w') as shapes_file:
|
||||
json.dump(shapes, shapes_file)
|
89
data_processor.py
Normal file
89
data_processor.py
Normal file
@ -0,0 +1,89 @@
|
||||
"""
|
||||
Prepare input data for Google's BERT Model.
|
||||
|
||||
Contains some functions from tensor2tensor library: https://github.com/tensorflow/tensor2tensor
|
||||
|
||||
"""
|
||||
from typing import NamedTuple, List, Union, Tuple
|
||||
|
||||
TokenizedSentence = List[str]
|
||||
TokenizedInput = Union[Tuple[TokenizedSentence, TokenizedSentence], TokenizedSentence]
|
||||
|
||||
class DataProcessor():
|
||||
def __init__(self, vocab_path):
|
||||
self.encoder_file_path = encoder_file_path
|
||||
self.token_indexer = json.load(open(vocab_path))
|
||||
|
||||
|
||||
def tokenize(text):
|
||||
"""Encode a unicode string as a list of tokens.
|
||||
|
||||
Args:
|
||||
text: a unicode string
|
||||
Returns:
|
||||
a list of tokens as Unicode strings
|
||||
"""
|
||||
if not text:
|
||||
return []
|
||||
ret = []
|
||||
token_start = 0
|
||||
# Classify each character in the input string
|
||||
is_alnum = [c in _ALPHANUMERIC_CHAR_SET for c in text]
|
||||
for pos in range(1, len(text)):
|
||||
if is_alnum[pos] != is_alnum[pos - 1]:
|
||||
token = text[token_start:pos]
|
||||
if token != u" " or token_start == 0:
|
||||
ret.append(token)
|
||||
token_start = pos
|
||||
final_token = text[token_start:]
|
||||
ret.append(final_token)
|
||||
return ret
|
||||
|
||||
|
||||
def detokenize(tokens):
|
||||
"""Decode a list of tokens to a unicode string.
|
||||
|
||||
Args:
|
||||
tokens: a list of Unicode strings
|
||||
Returns:
|
||||
a unicode string
|
||||
"""
|
||||
token_is_alnum = [t[0] in _ALPHANUMERIC_CHAR_SET for t in tokens]
|
||||
ret = []
|
||||
for i, token in enumerate(tokens):
|
||||
if i > 0 and token_is_alnum[i - 1] and token_is_alnum[i]:
|
||||
ret.append(u" ")
|
||||
ret.append(token)
|
||||
return "".join(ret)
|
||||
|
||||
def encode(input_sentences: List[TokenizedInput]) -> np.array:
|
||||
""" Prepare a torch.Tensor of inputs for BERT model from a string.
|
||||
|
||||
Args:
|
||||
input_sentences: list of
|
||||
- pairs of tokenized sentences (sentence_A, sentence_B) or
|
||||
- tokenized sentences (will be considered as sentence_A only)
|
||||
|
||||
Return:
|
||||
Numpy array of formated inputs for BERT model
|
||||
"""
|
||||
batch_size = sum(min(len(x), n_perso_permute) for x in X1)
|
||||
input_mask = np.zeros((n_batch, n_cands, n_ctx), dtype=np.float32)
|
||||
input_array = np.zeros((n_batch, n_cands, n_ctx, 3), dtype=np.int32)
|
||||
i = 0
|
||||
for tokenized_input in input_sentences:
|
||||
x1j, lxj, lperso, lhisto, dialog_embed = format_transformer_input(x1, x2, xcand_j, text_encoder,
|
||||
dialog_embed_mode, max_len=max_len,
|
||||
add_start_stop=True)
|
||||
lmj = len(xcand_j[:max_len]) + 1
|
||||
xmb[i, j, :lxj, 0] = x1j
|
||||
if dialog_embed_mode == 1 or dialog_embed_mode == 2:
|
||||
xmb[i, j, :lxj, 2] = dialog_embed
|
||||
mmb[i, j, :lxj] = 1
|
||||
if fix_lm_index: # Take one before so we don't predict from classify token...
|
||||
mmb_eval[i, j, (lxj-lmj-1):lxj-1] = 1 # This one only mask the response so we get the perplexity on the response only
|
||||
else:
|
||||
mmb_eval[i, j, (lxj-lmj):lxj] = 1 # This one only mask the response so we get the perplexity on the response only
|
||||
xmb[i, j, :, 1] = np.arange(n_vocab+n_special, n_vocab+n_special+n_ctx)
|
||||
i += 1
|
||||
return input_array, input_mask
|
5
download_weights.sh
Normal file
5
download_weights.sh
Normal file
@ -0,0 +1,5 @@
|
||||
echo "=== Downloading BERT pre-trained weights ==="
|
||||
echo "---"
|
||||
wget --quiet --continue http://www.fit.vutbr.cz/~imikolov/rnnlm/simple-examples.tgz
|
||||
tar -xzf simple-examples.tgz
|
||||
rm -rf simple-examples.tgz
|
18
example.py
Normal file
18
example.py
Normal file
@ -0,0 +1,18 @@
|
||||
"""
|
||||
Show how to use HuggingFace's PyTorch implementation of Google's BERT Model.
|
||||
"""
|
||||
from .bert_model import BERT
|
||||
from .prepare_inputs import DataPreprocessor
|
||||
|
||||
bert_model = BERT()
|
||||
bert_model.load_from('.')
|
||||
data_processor = DataProcessor(encoder_file_path='.')
|
||||
|
||||
input_sentence = "We are playing with the BERT model."
|
||||
print("BERT inputs: {}".format(input_sentence))
|
||||
|
||||
tensor_input = data_processor.encode(input_sentence)
|
||||
tensor_output = bert_model(prepared_input)
|
||||
output_sentence = data_processor.decode(tensor_output)
|
||||
|
||||
print("BERT predicted: {}".format(output_sentence))
|
Loading…
Reference in New Issue
Block a user